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Liu Y, Zhang J, Hu Z, Zhong Z, Yuan X. Acute effects of eccentric overload training with different loading doses in male sprinters. Heliyon 2024; 10:e32369. [PMID: 38947482 PMCID: PMC11214358 DOI: 10.1016/j.heliyon.2024.e32369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 04/30/2024] [Accepted: 06/03/2024] [Indexed: 07/02/2024] Open
Abstract
Objective The primary objective of this study was to investigate the immediate effects of two doses (Dose1 and Dose2,D1 and D2) of inertial Flywheel Eccentric Overload (FEOL), Eccentric Hook (EH), and High-intensity Half Squat (HHS) on muscle explosiveness in male sprinters. Methods Twenty-one sub-elite male sprinters were randomly assigned to three groups: the FEOL group (n=7), the EH group (n=7), and the HSS group (n=7),Measurements of athletes' explosive jumps (CMJ, SJ, SLJ) heights, relative peak power indices, and 30-m sprint times were collected before and 6 min after the intervention. Results At D1 loading dose, CMJ, SJ jump height, and relative peak power increased significantly (p < 0.05) after HHS training intervention, while there was no significant change in FEOL and EH training (p > 0.05). At D2 loading dose, CMJ, SJ jump height, and relative peak power increased significantly (p < 0.01) after FEOL and EH training intervention, but at D2HHS intervention, these indexes tended to decrease (p < 0.05). None of the three training protocols significantly improved SLJ performance (p > 0.05). CMJ vertical jump height and relative peak power were significantly higher after D2FEOL and D2EH interventions than after D1HHS (P < 0.05). Conclusion D1HHS, D2FEOL and D2EH3 intervention methods can all improve the performance of sub-elite athletes in the 30-m test, CMJ test and SJ test. in the CMJ test, FEOL training demonstrated a higher acute augmentation effect compared to EH training.
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Affiliation(s)
- Yuhang Liu
- China Athletics College, Beijing Sport University, Beijing, China
| | - Junjie Zhang
- Graduate School, Capital University of Physical Education and Sports, Beijing, China
| | - Zhongzhong Hu
- Department of Sports Science, Wenzhou Medical University, Zhejiang, China
| | - Zixuan Zhong
- Department of Sports and Physical Education, Macau Polytechnic University, China
| | - Xiaoyi Yuan
- China Athletics College, Beijing Sport University, Beijing, China
- State General Administration of Sport Key Laboratory of Sports Training, Beijing, China
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Yoshida R, Murakami Y, Kasahara K, Sato S, Nosaka K, Nakamura M. Minimum Intensity of Daily Six Eccentric Contractions to Increase Muscle Strength and Size. Scand J Med Sci Sports 2024; 34:e14683. [PMID: 38898582 DOI: 10.1111/sms.14683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2024] [Revised: 05/06/2024] [Accepted: 06/04/2024] [Indexed: 06/21/2024]
Abstract
Our previous study showed that daily six maximal eccentric contractions that were performed 5 days a week for 4 weeks increased maximal voluntary isometric (MVC-ISO), concentric (MVC-CON), and eccentric contraction (MVC-ECC) strength of the elbow flexors and muscle thickness of biceps brachii and brachialis (MT) by 8.3 ± 4.9%, 11.1 ± 7.4%, 13.5 ± 11.5%, and 10.6 ± 5.1%, respectively. In the present study, we tested the hypothesis that the muscle strength and MT would still increase when the training intensity was reduced to 2/3 or 1/3 of the peak MVC-ECC torque. Thirty-six healthy young (19-24 years) adults who had not performed resistance training were placed to three groups (n = 12/group): 2/3MVC or 1/3MVC that performed six eccentric contractions with 2/3 or 1/3 MVC-ECC load using a dumbbell 5 days a week for 4 weeks or control group that did not perform any training. Changes in the MVC-ISO, MVC-CON, MVC-ECC torque, and MT before and after the 4-week period were compared among the groups and with the group of the previous study in which six maximal eccentric contractions were performed 5 days a week for 4 weeks (MVC group; n = 12). The control and 1/3MVC groups showed no significant changes in any measures. Significant (p < 0.05) increases in MVC-ISO (10.3 ± 11.4%), MVC-CON (10.9 ± 9.5%), and MVC-ECC (9.3 ± 8.8%) torque and MT (10.1 ± 9.2%) were observed for the 2/3MVC group. These changes were not significantly different from those of the MVC group. These results suggest that the 2/3-intensity eccentric contractions with a dumbbell are as effective as maximal-intensity isokinetic eccentric contractions to induce muscle adaptations.
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Affiliation(s)
- Riku Yoshida
- Department of Rehabilitation Medicine, Maniwa Orthopedics Clinic, Niigata, Japan
| | - Yuta Murakami
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan
| | - Kazuki Kasahara
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan
| | - Shigeru Sato
- Department of Rehabilitation, Matsumura General Hospital, Iwaki, Japan
| | - Kazunori Nosaka
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia
| | - Masatoshi Nakamura
- Faculty of Rehabilitation Sciences, Nishi Kyushu University, Saga, Japan
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Jin Z, Liu G, Zhu H, Zheng Z, Pan X, Pan H. Does swing leg braking matter in long jump take-off? A 3-D kinematic analysis based on elite athletes. Heliyon 2024; 10:e31015. [PMID: 38813208 PMCID: PMC11133768 DOI: 10.1016/j.heliyon.2024.e31015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 05/08/2024] [Accepted: 05/09/2024] [Indexed: 05/31/2024] Open
Abstract
The objective of this study was to explore the braking technical characteristics of the swing leg of elite male athletes in long jump take-off and its dependencies on the extension velocity of the support leg and the balance. Two cameras were used to capture 8 elite male long jump athletes (25.88 ± 3.00 years) under competitive conditions at a National Indoor Athletic Championships Final, a 3-D kinematic analysis method was conducted to analyze the take-off technique of the athletes. The results showed that the rapid braking of the swing leg increased the extension velocity of the support leg. Compared to the swing leg that started braking at the moment of maximum knee flexion of the support leg (SPKnee maximum flexion moment), athletes' performance was greater when swing leg started braking at the moment of maximum ankle flexion of the support leg (SPAnkle maximum flexion moment). Furthermore, the swing leg exhibited an inward movement during its forward swing, and the inward angle was significantly correlated with the balance maintenance (r = - 0.50,P = 0.004). In conclusion, a relatively delayed rapid braking and moderate inward movement of the swing leg during the take-off phase are conducive to achieving a better take-off effect in long jump.
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Affiliation(s)
| | - Gongju Liu
- Scientific Research Department, Zhejiang College of Sports, Hangzhou, China
| | - Houwei Zhu
- College of Physical Education and Health Science, Zhejiang Normal University, China
| | - Zhe Zheng
- College of Physical Education and Health Science, Zhejiang Normal University, China
| | - Xu Pan
- Scientific Research Department, Zhejiang College of Sports, Hangzhou, China
| | - Huiju Pan
- College of Physical Education and Health Science, Zhejiang Normal University, China
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Hinks A, Patterson MA, Njai BS, Power GA. Age-related blunting of serial sarcomerogenesis and mechanical adaptations following 4 wk of maximal eccentric resistance training. J Appl Physiol (1985) 2024; 136:1209-1225. [PMID: 38511212 DOI: 10.1152/japplphysiol.00041.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 02/26/2024] [Accepted: 03/13/2024] [Indexed: 03/22/2024] Open
Abstract
During aging, muscles undergo atrophy, which is partly accounted for by a loss of sarcomeres in series. Serial sarcomere number (SSN) is associated with aspects of muscle mechanical function including the force-length and force-velocity-power relationships; hence, the age-related loss of SSN contributes to declining performance. Training emphasizing eccentric contractions increases SSN in young healthy rodents; however, the ability for eccentric training to increase SSN in old age is unknown. Ten young (8 mo) and 11 old (32 mo) male Fisher344/BN rats completed 4 wk of unilateral eccentric plantar flexion training. Pre- and posttraining, the plantar flexors were assessed for the torque-frequency, passive torque-angle, and torque-velocity-power relationships. The soleus, lateral gastrocnemius (LG), and medial gastrocnemius (MG) were harvested for SSN assessment via laser diffraction, with the untrained leg used as a control. In the untrained leg/pretraining, old rats had lower SSN in the soleus, LG, and MG, lower maximum torque, power, and shortening velocity, and greater passive torque than young. Young showed increased soleus and MG SSN following training. In contrast, old had no change in soleus SSN and experienced SSN loss in the LG. Pre- to posttraining, young experienced an increase in maximum isometric torque, whereas old had reductions in maximum torque, shortening velocity, and power, and increased passive torque. Our results show that although young muscle has the ability to add sarcomeres in response to maximal eccentric training, this stimulus could be not only ineffective, but also detrimental to aged muscle leading to dysfunctional remodeling.NEW & NOTEWORTHY The loss of sarcomeres in series with age contributes to declining muscle performance. The present study investigated whether eccentric training could improve performance via serial sarcomere addition in old muscle, like in young muscle. Four weeks of maximal eccentric training induced serial sarcomere addition in the young rat plantar flexors and improved in vivo performance, however, led to dysfunctional remodeling accompanied by further impaired performance in old rats.
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Affiliation(s)
- Avery Hinks
- Department of Human Health and Nutritional Sciences, College of Biological SciencesUniversity of GuelphGuelphOntarioCanada
| | - Makenna A Patterson
- Department of Human Health and Nutritional Sciences, College of Biological SciencesUniversity of GuelphGuelphOntarioCanada
| | - Binta S Njai
- Department of Human Health and Nutritional Sciences, College of Biological SciencesUniversity of GuelphGuelphOntarioCanada
| | - Geoffrey A Power
- Department of Human Health and Nutritional Sciences, College of Biological SciencesUniversity of GuelphGuelphOntarioCanada
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Nuzzo JL, Pinto MD, Kirk BJC, Nosaka K. Resistance Exercise Minimal Dose Strategies for Increasing Muscle Strength in the General Population: an Overview. Sports Med 2024; 54:1139-1162. [PMID: 38509414 PMCID: PMC11127831 DOI: 10.1007/s40279-024-02009-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/23/2024] [Indexed: 03/22/2024]
Abstract
Many individuals do not participate in resistance exercise, with perceived lack of time being a key barrier. Minimal dose strategies, which generally reduce weekly exercise volumes to less than recommended guidelines, might improve muscle strength with minimal time investment. However, minimal dose strategies and their effects on muscle strength are still unclear. Here our aims are to define and characterize minimal dose resistance exercise strategies and summarize their effects on muscle strength in individuals who are not currently engaged in resistance exercise. The minimal dose strategies overviewed were: "Weekend Warrior," single-set resistance exercise, resistance exercise "snacking," practicing the strength test, and eccentric minimal doses. "Weekend Warrior," which minimizes training frequency, is resistance exercise performed in one weekly session. Single-set resistance exercise, which minimizes set number and session duration, is one set of multiple exercises performed multiple times per week. "Snacks," which minimize exercise number and session duration, are brief bouts (few minutes) of resistance exercise performed once or more daily. Practicing the strength test, which minimizes repetition number and session duration, is one maximal repetition performed in one or more sets, multiple days per week. Eccentric minimal doses, which eliminate or minimize concentric phase muscle actions, are low weekly volumes of submaximal or maximal eccentric-only repetitions. All approaches increase muscle strength, and some approaches improve other outcomes of health and fitness. "Weekend Warrior" and single-set resistance exercise are the approaches most strongly supported by current research, while snacking and eccentric minimal doses are emerging concepts with promising results. Public health programs can promote small volumes of resistance exercise as being better for muscle strength than no resistance exercise at all.
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Affiliation(s)
- James L Nuzzo
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia.
| | - Matheus D Pinto
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia
| | - Benjamin J C Kirk
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia
| | - Kazunori Nosaka
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia
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Calandrini A, Penna EM, Monteiro EP, Boullosa D, Coswig VS. Effects of Eccentric Phase Velocity on Bench Press Concentric Bar Velocity in the Young and Elderly. Int J Sports Med 2024; 45:369-376. [PMID: 38346688 DOI: 10.1055/a-2235-1694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2024]
Abstract
This study aimed to investigate the impact of bar velocity during the eccentric phase on subsequent concentric performance in the young and elderly. Twelve elderly women (65.2+4.2 years) and 16 young women (23.1+2.1 years) were randomly assigned to four experimental conditions that combined high-velocity eccentric actions (HVECC; maximum velocity) and moderate-velocity eccentric actions (MVECC; 2.0 s), using 30% and 60% of their 1-repetition maximum (1RM) on the Smith machine bench press. Measurements of mean propulsive velocity (MPV), peak velocity (PV), and mean power (MP) were recorded. Two-way ANOVA with repeated measures was applied for each variable, when needed, the Bonferroni post hoc was used. Statistical significance was set at p<0.05, and effect size (ES) was established by Cohen's d z. The results demonstrated that elderly women showed improved performance in MPV (+10.0%; ES=- 0.58; p=0.009) and MP (+11.7%; ES=- 0.14; p=0.045) when utilizing HVECC at 30% 1RM only. Moreover, young women exhibited superior performance for both 30% and 60% 1RM when using HVECC for all variables analyzed (p<0.05). The HVECC appears to have an impact on the subsequent performance of the concentric phase, particularly when lighter loads (30% 1RM) are utilized, regardless of the age group.
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Affiliation(s)
- Antenor Calandrini
- Programa de Pós-graduação em Ciências do Movimento Humano, Universidade Federal do Pará - Campus Castanhal, Castanhal, Brazil
| | - Eduardo Macedo Penna
- Programa de Pós-graduação em Ciências do Movimento Humano, Universidade Federal do Pará - Campus Castanhal, Castanhal, Brazil
| | - Elren Passos Monteiro
- Programa de Pós-graduação em Ciências do Movimento Humano, Universidade Federal do Pará - Campus Castanhal, Castanhal, Brazil
| | - Daniel Boullosa
- Faculty of Sports Sciences and Physical Activity, Universidad de León, León, Spain
| | - Victor Silveira Coswig
- Instituto de Educação Física e Esportes, Universidade Federal do Ceará, Fortaleza, Brazil
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7
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Baxter BA, Baross AW, Ryan DJ, Tkadlec S, Kay AD. Effects of once- versus twice-weekly eccentric resistance training on muscular function and structure in older adults: a randomised controlled trial. Sci Rep 2024; 14:9638. [PMID: 38671049 PMCID: PMC11053087 DOI: 10.1038/s41598-024-59788-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 04/15/2024] [Indexed: 04/28/2024] Open
Abstract
Adherence rates to current twice-weekly strength training guidelines are poor among older adults. Eccentric-only training elicits substantial improvements in muscle function/size so the aim of this study was to compare the effects of once- versus twice-weekly eccentric training programmes on muscle function/size in older adults. Thirty-six participants (69.4 ± 6.0 yr) were randomised into non-active control, once-, or twice-weekly training groups. Lower-limb muscle power, strength, and size were assessed at baseline, mid-, and post-eccentric training. Training was performed for 12 min per session at 50% of maximum eccentric strength. Significant increases in power (13%), isometric (17-36%) and eccentric (40-50%) strength, and VL muscle thickness (9-18%) occurred in both training groups following 12 weeks. Minimal muscle soreness was induced throughout the 12 weeks and perceived exertion was consistently lower in the twice-weekly training group. One weekly submaximal eccentric resistance training session over 12 weeks elicits similar improvements in neuromuscular function compared to the currently recommended twice-weekly training dose. Given the substantial improvements in neuromuscular function and previously reported low adherence to current twice-weekly training guidelines, eccentric training may be pivotal to developing a minimal-dose strategy to counteract neuromuscular decline. The trial was registered retrospectively on 24/01/2024 with ISRCTN (trial registration number: ISRCTN68730580).
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Affiliation(s)
- Brett A Baxter
- Centre for Physical Activity and Life Sciences, Faculty of Art, Science and Technology, University of Northampton, Northamptonshire, NN1 5PH, UK.
| | - Anthony W Baross
- Centre for Physical Activity and Life Sciences, Faculty of Art, Science and Technology, University of Northampton, Northamptonshire, NN1 5PH, UK
| | - Declan J Ryan
- Centre for Physical Activity and Life Sciences, Faculty of Art, Science and Technology, University of Northampton, Northamptonshire, NN1 5PH, UK
| | - Stepan Tkadlec
- Centre for Physical Activity and Life Sciences, Faculty of Art, Science and Technology, University of Northampton, Northamptonshire, NN1 5PH, UK
- Healthy Longevity Clinic, 165 East Palmetto Park Road, Boca Raton, FL, 33432, USA
- Healthy Longevity Clinic, Zlatniky-Hodkovice, 252 41, Prague, Czech Republic
| | - Anthony D Kay
- Centre for Physical Activity and Life Sciences, Faculty of Art, Science and Technology, University of Northampton, Northamptonshire, NN1 5PH, UK
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8
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Perret C, Käch M, Hertig-Godeschalk A, Ammann F. Strength and power adaptations of the upper body following 20 training sessions on an eccentric arm-crank ergometer. Eur J Appl Physiol 2024:10.1007/s00421-024-05486-3. [PMID: 38656379 DOI: 10.1007/s00421-024-05486-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 04/04/2024] [Indexed: 04/26/2024]
Abstract
PURPOSE Eccentric strength training is an innovative and promising approach to improve exercise performance. However, most eccentric training studies in the past were performed with a focus on the lower extremities. The present study aimed to test the feasibility and effects on strength and power adaptations of a structured upper-body eccentric training program. METHODS Fourteen (median age (Q1-Q3) 29 years (27-32); 9 females, 5 males) healthy, regularly exercising individuals performed 20 progressive training sessions (2-3 sessions/week at 20-50% peak power for 8-14 min) on a symmetric eccentric arm-crank ergometer. Before and after the intervention, anaerobic peak power (PP) and maximal concentric aerobic power output (POmax) on an arm-crank ergometer as well as the one repetition maximum (1RM) for bench press were determined as main outcome parameters. A p-value ≤ 0.05 was considered statistically significant. RESULTS Significant improvements in PP (+ 4% (1-8), p = 0.007), POmax (+ 6% (0-8); p = 0.01), and 1RM (+ 12% (10-17); p < 0.001) were found. Exercise intensity was relatively low at 64% (55-70) of maximum heart rate. CONCLUSIONS Twenty progressive training sessions on a symmetric arm-crank ergometer are effective in inducing significant aerobic and anaerobic performance and strength improvements in the upper body. This intervention is safe and feasible, and can be performed at relatively low cardiovascular intensities. Therefore, this training method offers an interesting approach from elite sports to rehabilitation.
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Affiliation(s)
- Claudio Perret
- Swiss Paraplegic Research, Guido A. Zaech-Strasse 4, 6207, Nottwil, Switzerland
- Faculty of Health Sciences and Medicine, University of Lucerne, Lucerne, Switzerland
| | - Matheo Käch
- Institute of Human Movement Sciences and Sports, ETH Zurich, Zurich, Switzerland
- Institute of Sports Medicine, Swiss Paraplegic Centre, Nottwil, Switzerland
| | | | - Fabian Ammann
- Institute of Sports Medicine, Swiss Paraplegic Centre, Nottwil, Switzerland
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Ferreira RM, Fernandes LG, Franco S, Simões V, Sampaio AR. Occupational Health-Related Problems among Portuguese Fitness Instructors. Healthcare (Basel) 2024; 12:877. [PMID: 38727434 PMCID: PMC11083418 DOI: 10.3390/healthcare12090877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2024] [Revised: 04/17/2024] [Accepted: 04/21/2024] [Indexed: 05/13/2024] Open
Abstract
BACKGROUND The fitness sector has experienced significant expansion, with fitness instructors (FIs) playing a pivotal role. Given the demands of their profession, understanding their health profile is crucial. This study's purpose is to explore the prevalence of fitness instructors' occupational health-related problems. METHODS A questionnaire covering sociodemographic, occupational, and health-related items was administered. Statistical analyses, including Mann-Whitney U and chi-square tests, Spearman's rho correlations, and logistic regressions, were conducted. RESULTS Fifty-nine FIs reported occupational health-related problems, with the majority occurring during instruction (66.1%), being muscular (32.2%), and knee (15.3%), the most common type and localization. Significant statistical differences were observed between injured and non-injured FIs, including sex (p = 0.012), years as an FI (p = 0.001), weekly days worked (p = 0.039), and daily hours worked (p = 0.013). Weak negative (-0.284 - -0.362) statistically significant correlations were found between health problems; weight; height; main activity; and FIs in the workplace. Logistic regressions identified significant models showing that having a sport/physical exercise background and practicing it regularly were less likely to report bursitis (OR 0.018; p = 0.020) and hip injuries (OR 0.026; p = 0.037). CONCLUSIONS Approximately one-third of FIs reported occupational-related health problems, predominantly musculoskeletal injuries. Sociodemographic, personal, and occupational factors appear to influence the prevalence of these health problems.
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Affiliation(s)
- Ricardo Maia Ferreira
- Social Sciences, Education and Sport Department, Polytechnic Institute of Maia, N2i, 4475-690 Maia, Portugal;
- Physioterapy Department, Polytechnic Institute of Coimbra, Coimbra Health School, 3046-854 Coimbra, Portugal
- Sport Physical Activity and Health Research & Innovation Center (SPRINT), 4960-320 Melgaço, Portugal
| | - Luís Gonçalves Fernandes
- Social Sciences, Education and Sport Department, Polytechnic Institute of Maia, N2i, 4475-690 Maia, Portugal;
| | - Susana Franco
- Polytechinc Institute of Santarém, School of Sports of Rio Maior, 2040-413 Rio Maior, Portugal; (S.F.); (V.S.)
- Quality of Life Research Center (CIEQV), 2040-400 Santarém, Portugal
| | - Vera Simões
- Polytechinc Institute of Santarém, School of Sports of Rio Maior, 2040-413 Rio Maior, Portugal; (S.F.); (V.S.)
- Quality of Life Research Center (CIEQV), 2040-400 Santarém, Portugal
| | - António Rodrigues Sampaio
- Social Sciences, Education and Sport Department, Polytechnic Institute of Maia, N2i, 4475-690 Maia, Portugal;
- Research Center in Sports Sciences, Health Sciences and Human Development, CIDESD, University of Maia, 4475-690 Maia, Portugal
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10
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Medeiros DM, Lima-E-Silva FXD, Aimi M, Vaz MA, Baroni BM. Do athletes with hamstring strain injury have shorter muscle fascicles in the injured limb? J Bodyw Mov Ther 2024; 38:269-273. [PMID: 38763569 DOI: 10.1016/j.jbmt.2024.01.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 12/01/2023] [Accepted: 01/25/2024] [Indexed: 05/21/2024]
Abstract
INTRODUCTION Previous studies have suggested that a reduced length of the biceps femoris long head (BFlh) fascicles may increase the risk of hamstring strain injury (HSI). However, it remains unclear whether the BFlh fascicles of the injured limb are shorter than those of the contralateral limb in athletes with an acute HSI. OBJECTIVE To investigate the between-limb asymmetry of BFlh fascicle length in amateur athletes with an acute HSI. METHODS Male amateur athletes were evaluated using ultrasound scans within five days following an HSI. The BFlh fascicle length was estimated using a validated equation. RESULTS Eighteen injured athletes participated in this study. There was no significant difference (p = 0.27) in the length of BFlh fascicles between the injured limb (9.53 ± 2.55 cm; 95%CI 8.26 to 10.80 cm) and the uninjured limb (10.54 ± 2.87 cm; 95%CI 9.11 to 11.97 cm). Individual analysis revealed high heterogeneity, with between-limb asymmetries (percentage difference of the injured limb compared to the uninjured limb) ranging from -42% to 25%. Nine out of the 18 athletes had a fascicle length that was more than 10% shorter in the injured limb compared to the uninjured limb, five athletes had a difference of less than 10%, and four athletes had a fascicle length that was more than 10% longer in the injured limb compared to the uninjured limb. CONCLUSION The architecture characteristics of injured and uninjured muscles is not consistent among athletes with HSI. Therefore, rehabilitation programs focused on fascicle lengthening should be evaluated on a case-by-case basis.
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Affiliation(s)
| | | | - Mateus Aimi
- Federal University of Rio Grande do Sul, Porto Alegre, Brazil
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11
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Hall KB, Immink MA, Martin DT, Bennett H, Crowther RG. Dose-Response Effect of an Inertia Flywheel Postactivation Performance Enhancement Protocol on Countermovement Jump Performance. J Appl Biomech 2024; 40:147-154. [PMID: 38176403 DOI: 10.1123/jab.2023-0217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 11/08/2023] [Accepted: 12/01/2023] [Indexed: 01/06/2024]
Abstract
The purpose of this study was to investigate the dose-response effect of a high-load, 6-repetition, maximum effort inertial flywheel (IFw) squat postactivation performance enhancement (PAPE) protocol on countermovement jump (CMJ) performance metrics. Thirteen subjects completed 5 squat testing sessions: 1 session to determine back-squat 6-repetition maximum, 1 session to determine 6-repetition maximum IFw load, and 3 sessions to investigate the dose-response effect of an IFw PAPE protocol set at the load determined in the second session. In the IFw PAPE sessions, subjects completed either 1, 2, or 3 sets of IFw squats, then performed 5 CMJs over 12 minutes (1, 3, 6, 9, and 12 min post-IFw). All CMJ tests were conducted on a force platform where CMJ performance outcomes and impulse variables were calculated. There was no main time or volume effect for jump height, contact time, reactive strength index, peak force, or any of the impulse variables. A main time effect was identified for flight time (P = .006, effect size = 0.24) and peak power (P = .001, effect size = 0.28). The lack of change in jump height may indicate that too much fatigue was generated following this near-maximal IFw squat protocol, thereby reducing the PAPE effect.
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Affiliation(s)
- Keegan B Hall
- UniSA: Allied Health and Human Performance, University of South Australia, Adelaide, SA, Australia
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, SA, Australia
| | - Maarten A Immink
- UniSA: Allied Health and Human Performance, University of South Australia, Adelaide, SA, Australia
- Sport, Health, Activity, Performance and Exercise Research Centre and College of Nursing and Health Sciences, Flinders University, Adelaide, SA, Australia
| | - David T Martin
- School of Behavioural and Health Sciences, Australian Catholic University, Melbourne, VIC, Australia
| | - Hunter Bennett
- UniSA: Allied Health and Human Performance, University of South Australia, Adelaide, SA, Australia
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, SA, Australia
| | - Robert G Crowther
- UniSA: Allied Health and Human Performance, University of South Australia, Adelaide, SA, Australia
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, SA, Australia
- School of Behavioural and Health Sciences, Australian Catholic University, Melbourne, VIC, Australia
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12
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Namsawang J, Srijunto W, Werasirirat P, Snieckus A, Bradauskiene K, Kamandulis S, Muanjai P. The effects of 6-week home-based static stretching, dynamic stretching, or eccentric exercise interventions on muscle-tendon properties and functional performance in older women. J Exerc Sci Fit 2024; 22:117-126. [PMID: 38283890 PMCID: PMC10820338 DOI: 10.1016/j.jesf.2024.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 12/20/2023] [Accepted: 01/03/2024] [Indexed: 01/30/2024] Open
Abstract
Background Joint inflexibility is acknowledged as a significant contributor to functional limitations in the older adult, with lengthening-type exercises identified as a potential remedial approach. Nevertheless, the responses to eccentric exercise in female older adults have not been extensively studied especially in home-based environment. Here, we aimed to assess the effectiveness of home-based static stretching (ST), dynamic closed-chain stretching (DCS), or eccentric exercise (ECC) interventions on flexibility, musculotendinous architecture, and functional ability in healthy older women. Methods We randomly assigned 51 healthy older women (age 65.9 ± 3.4 years) to one of three interventional exercise groups: DCS (N = 17), ECC (N = 17), or ST (N = 17). The training was performed 3 times a week for 6 weeks. The participants' musculotendinous stiffness, fascicle length, eccentric strength, and functional capacities were measured before the intervention, after 6 weeks of exercise, and at a 1-month follow-up. Results The results showed that all three interventions improved hamstring flexibility and passive ankle dorsiflexion (p < 0.001), with increased biceps femoris and medial gastrocnemius fascicle length (p < 0.01). However, there was no significant change in musculotendinous stiffness. The ECC intervention produced a greater improvement in knee flexor and calf eccentric peak torque (p < 0.05), and gait speed (p = 0.024) than the other two interventions. The changes in flexibility and knee flexor strength remained for up to 4 weeks after detraining. Conclusion In conclusion, the present study suggests that home-based ECC may be more beneficial in enhancing physical capacities in older women compared with either DCS or SS interventions.
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Affiliation(s)
- Juntip Namsawang
- Department of Physical Therapy, Allied Health Sciences Faculty, Burapha University, Chonburi, Thailand
- Exercise and Nutrition Innovation and Sciences Research Unit, Burapha University, Chonburi, Thailand
| | - Wirasinee Srijunto
- Department of Physical Therapy, Allied Health Sciences Faculty, Burapha University, Chonburi, Thailand
| | - Phurichaya Werasirirat
- Department of Physical Therapy, Allied Health Sciences Faculty, Burapha University, Chonburi, Thailand
- Exercise and Nutrition Innovation and Sciences Research Unit, Burapha University, Chonburi, Thailand
| | - Audrius Snieckus
- Institute of Sport Science and Innovations, Lithuanian Sports University, Kaunas, Lithuania
| | | | - Sigitas Kamandulis
- Institute of Sport Science and Innovations, Lithuanian Sports University, Kaunas, Lithuania
| | - Pornpimol Muanjai
- Department of Physical Therapy, Allied Health Sciences Faculty, Burapha University, Chonburi, Thailand
- Exercise and Nutrition Innovation and Sciences Research Unit, Burapha University, Chonburi, Thailand
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13
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Karabay D, Yeşilyaprak SS, Erduran M, Ozcan C. Effects of Eccentric Versus Concentric Strengthening in Patients With Subacromial Pain Syndrome: A Randomized Controlled Trial. Sports Health 2024:19417381241236817. [PMID: 38532530 DOI: 10.1177/19417381241236817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024] Open
Abstract
BACKGROUND Subacromial pain syndrome (SPS) is the most common cause of shoulder pain. Therapeutic exercise is the first-line treatment for SPS; however, the ideal exercise type remains unclear. Here, we compared the effects of eccentric and concentric strengthening in patients with SPS. HYPOTHESIS Adding isolated eccentric strengthening to a multimodal physiotherapy program (MPP) would lead to greater improvements in outcomes compared with either MPP alone or adding isolated concentric strengthening to the MPP. STUDY DESIGN Randomized controlled trial. LEVEL OF EVIDENCE Level 2. METHODS A total of 45 patients were randomized to eccentric strengthening (ESG), concentric strengthening (CSG), and control (CG) groups; all groups received the MPP. The strengthening groups also performed group-specific strengthening. Shoulder pain, abduction and external rotation (ER) strength, joint position sense (JPS), the Constant-Murley Score (CMS), and the Disabilities of the Arm, Shoulder and Hand score were collected at baseline, after 12 weeks of treatment, and at week 24. RESULTS For CMS, ESG exhibited a greater, but not clinically meaningful, improvement than CSG and CG (P < 0.05). Eccentric abduction strength increased in ESG compared with CG. From baseline to follow-up, abduction strength increased in ESG compared with CSG and CG. Eccentric abduction strength increased in CSG compared with CG. JPS at abduction improved in the ESG compared with CG. Other between-group comparisons were not significant (P > 0.05). CONCLUSION In SPS, eccentric strengthening provided added benefits, improving shoulder abduction strength and JPS at abduction, and was superior to concentric strengthening for improving shoulder abduction strength. Neither strengthening approach had an additional effect on shoulder function, pain, ER strength, or rotational JPS. CLINICAL RELEVANCE Clinicians could implement eccentric strengthening as a motor control retraining for strength and proprioception gain rather than for pain relief and reducing disability.
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Affiliation(s)
- Damla Karabay
- Department of Physiotherapy and Rehabilitation, Health Sciences Faculty, Izmir Katip Celebi University, Izmir, Turkey
- Institute of Health Sciences, Dokuz Eylul University, Izmir, Turkey
| | - Sevgi Sevi Yeşilyaprak
- Faculty of Physical Therapy and Rehabilitation, Dokuz Eylul University, Izmir, Turkey
- Department of Physiotherapy and Rehabilitation, Health Sciences Faculty, Bakircay University, Izmir, Turkey
| | - Mehmet Erduran
- Department of Orthopaedics and Traumatology, Faculty of Medicine, Dokuz Eylul University, Izmir, Turkey
| | - Cem Ozcan
- Department of Orthopedics and Traumatology, Faculty of Medicine, Izmir Katip Celebi University, Izmir, Turkey
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14
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McNeill C, Beaven CM, McMaster DT, Ward P, Gill N. Eccentric Force-Velocity-Load Relationship in Trained Rugby Union Athletes. J Strength Cond Res 2024; 38:549-555. [PMID: 38088926 DOI: 10.1519/jsc.0000000000004648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
ABSTRACT McNeill, C, Beaven, CM, McMaster, DT, Ward, P, and Gill, N. Eccentric force-velocity-load relationship in trained rugby union athletes. J Strength Cond Res 38(3): 549-555, 2024-The force-velocity relationship is traditionally believed to resemble a hyperbolic shape, known as the "force-velocity curve." However, there is less evidence regarding this relationship during eccentric muscle action in multijoint isotonic exercise, especially in applied settings. The purpose of this study was to investigate the force-velocity-load relationship in an incremental eccentric back squat test. In addition, 37 professional male rugby union athletes were recruited to participate. Separate generalized linear mixed models were used to analyze the effect of barbell load on relative eccentric peak force (REPF), relative eccentric mean force (REMF), eccentric peak velocity (EPV), and eccentric mean velocity (EMV). A significant effect of load ( p < 0.05) was observed for each of the eccentric variables tested. Each increase in barbell load tended to result in a linear increase in REMF and a decrease in EMV and EPV; however, we observed a plateauing effect for REPF as load increased. These results show that for "peak" variables lighter loads produced similar magnitudes of force, but generally moved at higher velocities than heavier loads. These observations suggest that the eccentric force-velocity-load relationship may vary depending on the parameters used. Quantifying rapid, multijoint eccentric performance is justified as it seems to provide valuable insight into individual athletic capability and training program design. Further research may investigate the responsiveness of the qualities to training and the causal nature of eccentric characteristics and athletic performance.
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Affiliation(s)
- Conor McNeill
- Te Huataki Waiora School of Health, Adams Centre for High Performance, The University of Waikato, Tauranga, New Zealand
- New Zealand Rugby Union, Wellington, New Zealand; and
| | - C Martyn Beaven
- Te Huataki Waiora School of Health, Adams Centre for High Performance, The University of Waikato, Tauranga, New Zealand
| | - Daniel T McMaster
- Te Huataki Waiora School of Health, Adams Centre for High Performance, The University of Waikato, Tauranga, New Zealand
- New Zealand Rugby Union, Wellington, New Zealand; and
| | | | - Nicholas Gill
- Te Huataki Waiora School of Health, Adams Centre for High Performance, The University of Waikato, Tauranga, New Zealand
- New Zealand Rugby Union, Wellington, New Zealand; and
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15
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Li DCW, Rudloff S, Langer HT, Norman K, Herpich C. Age-Associated Differences in Recovery from Exercise-Induced Muscle Damage. Cells 2024; 13:255. [PMID: 38334647 PMCID: PMC10854791 DOI: 10.3390/cells13030255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 01/23/2024] [Accepted: 01/24/2024] [Indexed: 02/10/2024] Open
Abstract
Understanding the intricate mechanisms governing the cellular response to resistance exercise is paramount for promoting healthy aging. This narrative review explored the age-related alterations in recovery from resistance exercise, focusing on the nuanced aspects of exercise-induced muscle damage in older adults. Due to the limited number of studies in older adults that attempt to delineate age differences in muscle discovery, we delve into the multifaceted cellular influences of chronic low-grade inflammation, modifications in the extracellular matrix, and the role of lipid mediators in shaping the recovery landscape in aging skeletal muscle. From our literature search, it is evident that aged muscle displays delayed, prolonged, and inefficient recovery. These changes can be attributed to anabolic resistance, the stiffening of the extracellular matrix, mitochondrial dysfunction, and unresolved inflammation as well as alterations in satellite cell function. Collectively, these age-related impairments may impact subsequent adaptations to resistance exercise. Insights gleaned from this exploration may inform targeted interventions aimed at enhancing the efficacy of resistance training programs tailored to the specific needs of older adults, ultimately fostering healthy aging and preserving functional independence.
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Affiliation(s)
- Donna Ching Wah Li
- Department of Nutrition and Gerontology, German Institute of Human Nutrition Potsdam-Rehbrücke, 14558 Nuthetal, Germany
- Institute of Nutritional Science, University of Potsdam, 14558 Nuthetal, Germany
| | - Stefan Rudloff
- Department of Geriatrics and Medical Gerontology, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13347 Berlin, Germany
| | | | - Kristina Norman
- Department of Nutrition and Gerontology, German Institute of Human Nutrition Potsdam-Rehbrücke, 14558 Nuthetal, Germany
- Institute of Nutritional Science, University of Potsdam, 14558 Nuthetal, Germany
- Department of Geriatrics and Medical Gerontology, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13347 Berlin, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Berlin, 10785 Berlin, Germany
| | - Catrin Herpich
- Department of Nutrition and Gerontology, German Institute of Human Nutrition Potsdam-Rehbrücke, 14558 Nuthetal, Germany
- Institute of Nutritional Science, University of Potsdam, 14558 Nuthetal, Germany
- Department of Geriatrics and Medical Gerontology, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13347 Berlin, Germany
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16
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Vigouroux L, Devise M. Pull-Up Performance Is Affected Differently by the Muscle Contraction Regimens Practiced during Training among Climbers. Bioengineering (Basel) 2024; 11:85. [PMID: 38247962 PMCID: PMC10813506 DOI: 10.3390/bioengineering11010085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/12/2024] [Accepted: 01/15/2024] [Indexed: 01/23/2024] Open
Abstract
Sport climbing performance is highly related to upper limb strength and endurance. Although finger-specific methods are widely analyzed in the literature, no study has yet quantified the effects of arm-specific training. This study aims to compare the effects of three types of training involving different muscle contraction regimens on climbers' pull-up capabilities. Thirty advanced to high-elite climbers were randomly divided into four groups: eccentric (ECC; n = 8), isometric (ISO; n = 7), plyometric (PLYO; n = 6), and no specific training (CTRL; n = 9), and they participated in a 5-week training, twice a week, focusing on pull-ups on hangboard. Pre- and post-training assessments were conducted using a force-sensing hangboard, analyzing force, velocity, power, and muscle work during three pull-up exercises: pull-ups at body weight under different conditions, incremental weighted pull-ups, and an exhaustion test. The CTRL group showed no change. Maximum strength improved in all three training groups (from +2.2 ± 3.6% to +5.0 ± 2.4%; p < 0.001); velocity variables enhanced in the ECC and PLYO groups (from +5.7 ± 7.4 to +28.7 ± 42%; p < 0.05), resulting in greater power; amplitude increased in the ECC group; and muscle work increased in the PLYO group (+21.9 ± 16.6%; p = 0.015). A 5-week training period effectively enhanced arm performance, but outcomes were influenced by the chosen muscle contraction regimens and initial individual characteristics.
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Affiliation(s)
- Laurent Vigouroux
- ISM (Institute of Movement Sciences), CNRS, Aix-Marseille University, 13288 Marseille, France;
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17
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Mcleod JC, Currier BS, Lowisz CV, Phillips SM. The influence of resistance exercise training prescription variables on skeletal muscle mass, strength, and physical function in healthy adults: An umbrella review. JOURNAL OF SPORT AND HEALTH SCIENCE 2024; 13:47-60. [PMID: 37385345 PMCID: PMC10818109 DOI: 10.1016/j.jshs.2023.06.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 04/18/2023] [Accepted: 05/15/2023] [Indexed: 07/01/2023]
Abstract
PURPOSE The aim of this umbrella review was to determine the impact of resistance training (RT) and individual RT prescription variables on muscle mass, strength, and physical function in healthy adults. METHODS Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we systematically searched and screened eligible systematic reviews reporting the effects of differing RT prescription variables on muscle mass (or its proxies), strength, and/or physical function in healthy adults aged >18 years. RESULTS We identified 44 systematic reviews that met our inclusion criteria. The methodological quality of these reviews was assessed using A Measurement Tool to Assess Systematic Reviews; standardized effectiveness statements were generated. We found that RT was consistently a potent stimulus for increasing skeletal muscle mass (4/4 reviews provide some or sufficient evidence), strength (4/6 reviews provided some or sufficient evidence), and physical function (1/1 review provided some evidence). RT load (6/8 reviews provided some or sufficient evidence), weekly frequency (2/4 reviews provided some or sufficient evidence), volume (3/7 reviews provided some or sufficient evidence), and exercise order (1/1 review provided some evidence) impacted RT-induced increases in muscular strength. We discovered that 2/3 reviews provided some or sufficient evidence that RT volume and contraction velocity influenced skeletal muscle mass, while 4/7 reviews provided insufficient evidence in favor of RT load impacting skeletal muscle mass. There was insufficient evidence to conclude that time of day, periodization, inter-set rest, set configuration, set end point, contraction velocity/time under tension, or exercise order (only pertaining to hypertrophy) influenced skeletal muscle adaptations. A paucity of data limited insights into the impact of RT prescription variables on physical function. CONCLUSION Overall, RT increased muscle mass, strength, and physical function compared to no exercise. RT intensity (load) and weekly frequency impacted RT-induced increases in muscular strength but not muscle hypertrophy. RT volume (number of sets) influenced muscular strength and hypertrophy.
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Affiliation(s)
- Jonathan C Mcleod
- Department of Kinesiology, Faculty of Science, McMaster University, Hamilton L8S4L8, Canada
| | - Brad S Currier
- Department of Kinesiology, Faculty of Science, McMaster University, Hamilton L8S4L8, Canada
| | - Caroline V Lowisz
- Department of Kinesiology, Faculty of Science, McMaster University, Hamilton L8S4L8, Canada
| | - Stuart M Phillips
- Department of Kinesiology, Faculty of Science, McMaster University, Hamilton L8S4L8, Canada.
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18
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Borot L, Pageaux B, Laroche D, Vergotte G, Lepers R, Perrey S. Eccentric cycling involves greater mental demand and cortical activation of the frontoparietal network. Scand J Med Sci Sports 2024; 34:e14517. [PMID: 37814520 DOI: 10.1111/sms.14517] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 09/05/2023] [Accepted: 09/29/2023] [Indexed: 10/11/2023]
Abstract
Eccentric, compared to concentric exercise, is proposed to involve different neuro-motor processing strategies and a higher level of mental demand. This study compared eccentric and concentric cycling at matched perceived effort and torque for the mental demand and related-cortical activation patterns. Nineteen men (30 ± 6 years) performed four different 5-min cycling conditions at 30 RPM on a semi-recumbent isokinetic cycle ergometer: (1) concentric at a moderate perceived effort (23 on the CR100® scale) without torque feedback; (2) concentric and (3) eccentric at the same average torque produced in the first condition; and (4) eccentric at the same moderate perceived effort than the first concentric condition. The conditions two to four were randomized. After each condition, mental demand was monitored using the NASA Task Load Index scale. Changes in oxy-(O2 Hb) and deoxy-(HHb) hemoglobin during exercise were measured over both prefrontal cortices and the right parietal lobe from a 15-probe layout using a continuous-wave NIRS system. Mental demand was significantly higher during eccentric compared to concentric cycling (+52%, p = 0.012) and when the exercise intensity was fixed by the torque rather than the perceived effort (+70%, p < 0.001). For both torque- or perceived effort-matched exercises, O2 Hb increased significantly (p < 0.001) in the left and right prefrontal cortices, and right parietal lobe, and HHb decreased in the left, and right, prefrontal cortices during eccentric compared to concentric cycling. This study supports that acute eccentric cycling, compared to concentric cycling, involves a higher mental demand, and frontoparietal network activation.
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Affiliation(s)
- Lénaic Borot
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Benjamin Pageaux
- École de kinésiologie et des sciences de l'activité physique (EKSAP), Faculté de médecine, Montréal, Quebec, Canada
- Centre de recherche de l'Institut universitaire de gériatrie de Montréal (CRIUGM), Montréal, Quebec, Canada
- Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Montréal, Quebec, Canada
| | - Davy Laroche
- INSERM UMR 1093-CAPS, Univ. Bourgogne, UFR des Sciences du Sport, Dijon, France
- INSERM, CHU Dijon-Bourgogne, Centre d'Investigation Clinique CIC 1432, Module Plurithématique, Plateforme d'Investigation Technologique, Dijon, France
| | - Grégoire Vergotte
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France
| | - Romuald Lepers
- INSERM UMR 1093-CAPS, Univ. Bourgogne, UFR des Sciences du Sport, Dijon, France
| | - Stéphane Perrey
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France
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Murao M, Imano T, Sato Y, Nakajima M. Uphill running preferred over downhill running for recovery from glucocorticoid-induced muscle atrophy. Steroids 2024; 201:109337. [PMID: 37977489 DOI: 10.1016/j.steroids.2023.109337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 11/01/2023] [Accepted: 11/14/2023] [Indexed: 11/19/2023]
Affiliation(s)
- Masanobu Murao
- Research institute of health and welfare, Kibi international university, 8 Iga-machi, Takahashi-city, Okayama 716-8508, Japan; Rehabilitation unit, Kyoto university hospital, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto-city, Kyoto 606-8507, Japan.
| | - Tetsuo Imano
- Research institute of health and welfare, Kibi international university, 8 Iga-machi, Takahashi-city, Okayama 716-8508, Japan; Department of physical therapy, Hiroshima international and medical welfare collage, 14-22 Hijiyamahonmachi, Minami-ku, Hiroshima-city, Hiroshima 732-0816, Japan
| | - Yoshinobu Sato
- Research institute of health and welfare, Kibi international university, 8 Iga-machi, Takahashi-city, Okayama 716-8508, Japan; Studio TAIKA, 28-6 Shinyuno, Kannabe-cho, Fukuyama-city, Hiroshima 720-2122, Japan
| | - Masaaki Nakajima
- Research institute of health and welfare, Kibi international university, 8 Iga-machi, Takahashi-city, Okayama 716-8508, Japan
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Loturco I, Zabaloy S, Pereira LA, Moura TBMA, Mercer VP, Victor F, Zając A, Matusinski A, Freitas TT, Bishop C. Resistance Training Practices of Brazilian Olympic Sprint and Jump Coaches: Toward a Deeper Understanding of Their Choices and Insights (Part III). J Hum Kinet 2024; 90:183-214. [PMID: 38380293 PMCID: PMC10875694 DOI: 10.5114/jhk/182888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 01/20/2024] [Indexed: 02/22/2024] Open
Abstract
In the final part of this three-article collection on the training strategies of Brazilian Olympic sprint and jump coaches, we provide a detailed description of the resistance training methods and exercises most commonly employed by these speed experts. Always with the objective of maximizing the sprint and jump capabilities of their athletes, these experienced coaches primarily utilize variable, eccentric, concentric, machine-based, isometric, complex, and isoinertial resistance training methods in their daily practices. Squats (in their different forms), Olympic weightlifting, ballistics, hip thrusts, lunges, calf raises, core exercises, leg curls, stiff-leg deadlifts, and leg extension are the most commonly prescribed exercises in their training programs, during both the preparatory and competitive periods. Therefore, the current manuscript comprehensively describes and examines these methods, with the additional aim of extrapolating their application to other sports, especially those where sprint speed is a key performance factor.
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Affiliation(s)
- Irineu Loturco
- NAR—Nucleus of High Performance in Sport, São Paulo, Brazil
- Department of Human Movement Sciences, Federal University of São Paulo, São Paulo, Brazil
- Department of Sport, Health, and Exercise Science, University of South Wales, Pontypridd, Wales, United Kingdom
| | - Santiago Zabaloy
- Faculty of Physical Activity and Sports, University of Flores, Buenos Aires, Argentina
| | | | | | | | | | - Adam Zając
- Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education in Katowice, Katowice, Poland
| | - Aleksander Matusinski
- Department of Exercise and Sport Performance, The Jerzy Kukuczka Academy of Physical Education in Katowice, Katowice, Poland
| | - Tomás T. Freitas
- NAR—Nucleus of High Performance in Sport, São Paulo, Brazil
- UCAM Research Center for High Performance Sport, UCAM Universidad Católica de Murcia, Murcia, Spain
- Facultad de Deporte, UCAM Universidad Católica de Murcia, Murcia, Spain
| | - Chris Bishop
- London Sport Institute, Middlesex University, London, United Kingdom
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21
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Nuzzo JL, Nosaka K. Eccentric Muscle Actions Add Complexity to an Already Inconsistent Resistance Exercise Nomenclature. SPORTS MEDICINE - OPEN 2023; 9:118. [PMID: 38112984 PMCID: PMC10730477 DOI: 10.1186/s40798-023-00667-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Accepted: 12/06/2023] [Indexed: 12/21/2023]
Abstract
An eccentric muscle action (or contraction) is defined as active muscle lengthening against resistance, which occurs when the force generated by the muscle is smaller than the resistance placed upon it. Eccentric resistance exercise, which involves multiple sessions of repeated eccentric muscle actions, improves muscle strength and other health outcomes. In response to this evidence, new exercise technologies have been developed to permit feasible completion of eccentric muscle actions outside of the laboratory. Consequently, participation in eccentric resistance exercise is projected to increase in the future, and communications about eccentric resistance exercise are likely to reach a wide audience, including students in the classroom, athletes in the weightroom, patients who receive telehealth services, and journalists who report on study findings. Previous research has documented inconsistencies in how resistance exercises are named, but the role of eccentric resistance exercises has not been considered. Here, we explain how eccentric resistance exercises add further complexity to an already inconsistent resistance exercise nomenclature. Specifically, action words in exercise names typically describe the movement that occurs in the concentric phase (e.g., "press", "raise", "curl", "pull", "row"). This naming bias likely stems from the fact that traditional resistance exercise equipment, such as free weights and weight stack machines, does not typically accommodate for greater eccentric than concentric strength and thus emphasizes the concentric over eccentric phase. This naming bias is likely to hinder communications about eccentric resistance exercise. Thus, we encourage researchers and practitioners to discuss ways in which resistance exercises can be named more clearly and consistently.
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Affiliation(s)
- James L Nuzzo
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia.
| | - Kazunori Nosaka
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia
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Pakosz P, Konieczny M, Domaszewski P, Dybek T, Gnoiński M, Skorupska E. Comparison of concentric and eccentric resistance training in terms of changes in the muscle contractile properties. J Electromyogr Kinesiol 2023; 73:102824. [PMID: 37696055 DOI: 10.1016/j.jelekin.2023.102824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 06/29/2023] [Accepted: 09/06/2023] [Indexed: 09/13/2023] Open
Abstract
The habitual use of resistance exercises involving concentric and eccentric contractions can increase muscle strength, speed and endurance. However, current knowledge has limited potential to fully understand the application of such resistance training and the muscle changes that occur to differentiate these two types of training. The aim of this study was to compare the effects of concentric contraction (CON) and eccentric contraction (ECC) during an acute bout of resistance training on the hamstring contractile properties. A group of 20 female recreational athletes were divided into two equal groups, CON training and ECC training. The contractile properties of the muscles on both sides of the body were assessed using tensiomyography (TMG): biceps femoris (BF) and semitendinosus (ST). The muscles were assessed twice, before and after 10 maximal repetitions of either concentric or eccentric isotonic contractions. The results indicate a greater change in TMG parameters with ECC training, with p < 0.001 (Td and Tc). An acute bout of resistance training induces changes in the muscle hamstrings contractile properties in both CON and ECC training. Eccentric training causes greater changes than concentric training, shortening contraction time (Td, Tc), increase radial displacement velocity (Vrd) and affecting changes in muscle belly displacement (Dm), so may be more effective in training.
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Affiliation(s)
- Paweł Pakosz
- Faculty of Physical Education and Physiotherapy, Opole University of Technology, Opole, Poland.
| | - Mariusz Konieczny
- Faculty of Physical Education and Physiotherapy, Opole University of Technology, Opole, Poland
| | - Przemysław Domaszewski
- Department of Health Sciences, Institute of Health Sciences, University of Opole, Opole, Poland
| | - Tomasz Dybek
- Faculty of Physical Education and Physiotherapy, Opole University of Technology, Opole, Poland
| | | | - Elżbieta Skorupska
- Department of Physiotherapy, Poznan University of Medical Sciences, Poznań, Poland
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Lin TY, Chueh TY, Hung TM. Preferred Reporting Items for Resistance Exercise Studies (PRIRES): A Checklist Developed Using an Umbrella Review of Systematic Reviews. SPORTS MEDICINE - OPEN 2023; 9:114. [PMID: 38040927 PMCID: PMC10692055 DOI: 10.1186/s40798-023-00640-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Accepted: 09/26/2023] [Indexed: 12/03/2023]
Abstract
BACKGROUND The issues of replication and scientific transparency have been raised in exercise and sports science research. A potential means to address the replication crisis and enhance research reliability is to improve reporting quality and transparency. This study aims to formulate a reporting checklist as a supplement to the existing reporting guidelines, specifically for resistance exercise studies. METHODS PubMed (which covers Medline) and Scopus (which covers Medline, EMBASE, Ei Compendex, World Textile Index, Fluidex, Geobase, Biobase, and most journals in Web of Science) were searched for systematic reviews that comprised the primary studies directly comparing different resistance training methods. Basic data on the selected reviews, including on authors, publication years, and objectives, were summarized. The reporting items for the checklist were identified based on the objective of the reviews. Additional items from an existing checklist, namely the Consensus on Exercise Reporting Template, a National Strength and Conditioning Association handbook, and an article from the EQUATOR library were incorporated into the final reporting checklist. RESULTS Our database search retrieved 3595 relevant records. After automatic duplicate removal, the titles and abstracts of the remaining 2254 records were screened. The full texts of 137 records were then reviewed, and 88 systematic reviews that met the criteria were included in the umbrella review. CONCLUSION Developed primarily by an umbrella review method, this checklist covers the research questions which have been systematically studied and is expected to improve the reporting completeness of future resistance exercise studies. The PRIRES checklist comprises 26 reporting items (39 subitems) that cover four major topics in resistance exercise intervention: 1) exercise selection, performance, and training parameters, 2) training program and progression, 3) exercise setting, and 4) planned vs actual training. The PRIRES checklist was designed specifically for reporting resistance exercise intervention. It is expected to be used with other reporting guidelines such as Consolidated Standards of Reporting Trials and Standard Protocol Items: Recommendations for Interventional Trials. This article presents only the development process and resulting items of the checklist. An accompanying article detailing the rationale for, the importance of, and examples of each item is being prepared. REGISTRATION This study is registered with the EQUATOR Network under the title "Preferred Reporting Items for Resistance Exercise Studies (PRIRES)." PROSPERO registration number: CRD42021235259.
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Affiliation(s)
- Ting-Yu Lin
- Department of Physical Education and Sport Sciences, National Taiwan Normal University, No. 162, Section 1, Heping East Road, Da'an District, Taipei City, 106, Taiwan
| | - Ting-Yu Chueh
- Department of Physical Education and Sport Sciences, National Taiwan Normal University, No. 162, Section 1, Heping East Road, Da'an District, Taipei City, 106, Taiwan
| | - Tsung-Min Hung
- Department of Physical Education and Sport Sciences, National Taiwan Normal University, No. 162, Section 1, Heping East Road, Da'an District, Taipei City, 106, Taiwan.
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Diao L, Peng Y, Wang J, Chen J, Wang G, Jia S, Zheng C. Eccentric Contraction Enhances Healing of the Bone-Tendon Interface After Rotator Cuff Repair in Mice. Am J Sports Med 2023; 51:3835-3844. [PMID: 37861235 DOI: 10.1177/03635465231202901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
BACKGROUND Various muscle contraction modalities have differing effects on the musculoskeletal system. To understand the magnitude of these effects, the authors investigated the effects of eccentric and concentric contractions on the bone-tendon interface after rotator cuff repair in mice. HYPOTHESIS Eccentric contraction promotes healing of the bone-tendon interface after rotator cuff repair in mice better than other muscle contraction patterns. STUDY DESIGN Controlled laboratory study. METHODS The authors performed acute supraspinatus tendon repair of the right shoulder in 104 C57BL/6 mice. Animals were randomized into 4 groups postoperatively: control group (Con group), horizontal running group (Horz group), +15° uphill running group (Up group), and -15° downhill running group (Down group), with 26 animals in each group. At 4 and 8 weeks postoperatively, the authors removed the eyeball, collected blood samples, and extracted the supraspinatus tendon-humerus complex for histological, immunological, bone morphological, and biomechanical tests. RESULTS At 4 and 8 weeks postoperatively, the Down group exhibited a better collagen cell arrangement and fibrocartilage layer than the other 3 groups. At 4 weeks postoperatively, anti-inflammatory macrophages (M2 macrophages) were observed at the repair site in all groups except for the Con group. At 8 weeks postoperatively, M2 macrophages were withdrawn from the tendon site in all groups. The transforming growth factor β1 concentration in the Down group was greater than that in the other 3 groups at 4 weeks postoperatively, and it was higher than that in the Con group at 8 weeks postoperatively. The bone volume fraction, number of trabeculae, and thickness of trabeculae at the repair site in the Down group, as well as the ultimate strength and failure load in the biomechanical tests, were greater than those in the other 3 groups at 8 weeks postoperatively. CONCLUSION Eccentric contraction promotes healing of the bone-tendon interface after rotator cuff repair in mice better than other muscle contraction patterns. CLINICAL RELEVANCE After clinical rotator cuff repair, patients can be rehabilitated by eccentric training to speed up the functional recovery of the shoulder joint.
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Affiliation(s)
- Luyu Diao
- College of Sports Medicine, Wuhan Sports University, Wuhan, China
| | - Yundong Peng
- School of Sports Medicine and Rehabilitation, Beijing Sport University, Beijing, China
| | - Juan Wang
- College of Sports Medicine, Wuhan Sports University, Wuhan, China
| | - Jian Chen
- College of Sports Medicine, Wuhan Sports University, Wuhan, China
| | - Guanglan Wang
- College of Sports Medicine, Wuhan Sports University, Wuhan, China
| | - Shaohui Jia
- Hubei Key Laboratory of Sport Training and Monitoring, College of Sports Medicine, Wuhan Sports University, Wuhan, China
| | - Cheng Zheng
- Department of Sports Medicine, Affiliated Hospital, Wuhan Sports University, Wuhan, China
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Vila-Chã C, Bovolini A, Francisco C, Costa-Brito AR, Vaz C, Rua-Alonso M, de Paz JA, Vieira T, Mendonca GV. Acute effects of isotonic eccentric exercise on the neuromuscular function of knee extensors vary according to the motor task: impact on muscle strength profiles, proprioception and balance. Front Sports Act Living 2023; 5:1273152. [PMID: 38022776 PMCID: PMC10655025 DOI: 10.3389/fspor.2023.1273152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Accepted: 10/18/2023] [Indexed: 12/01/2023] Open
Abstract
Introduction Eccentric exercise has often been reported to result in muscle damage, limiting the muscle potential to produce force. However, understanding whether these adverse consequences extend to a broader, functional level is of apparently less concern. In this study, we address this issue by investigating the acute and delayed effects of supramaximal isotonic eccentric exercise on neuromuscular function and motor performance of knee extensors during tasks involving a range of strength profiles, proprioception, and balance. Methods Fifteen healthy volunteers (23.2 ± 2.9 years old) performed a unilateral isotonic eccentric exercise of the knee extensors of their dominant lower limb (4 × 10 reps at 120% of one Repetition Maximum (1RM)). The maximum voluntary isometric contraction (MVC), rate of force development (RFD), force steadiness of the knee extensors, as well as knee joint position sense and mediolateral (MLI) and anteroposterior stability (API) of the dominant lower limb, were measured pre-, immediately, and 24 h after the eccentric exercise. The EMG amplitude of the vastus medialis (VM) and biceps femoris (BF) were concomitantly evaluated. Results MVC decreased by 17.9% immediately after exercise (P < 0.001) and remained reduced by 13.6% 24 h following exercise (P < 0.001). Maximum RFD decreased by 20.4% immediately after exercise (P < 0.001) and remained reduced by 15.5% at 24 h (P < 0.001). During the MVC, EMG amplitude of the VM increased immediately after exercise while decreasing during the RFD task. Both values returned to baseline 24 h after exercise. Compared to baseline, force steadiness during submaximal isometric tasks reduced immediately after exercise, and it was accompanied by an increase in the EMG amplitude of the VM. MLI and knee joint position sense were impaired immediately after isotonic eccentric exercise (P < 0.05). While MLI returned to baseline values 24 h later, the absolute error in the knee repositioning task did not. Discussion Impairments in force production tasks, particularly during fast contractions and in the knee joint position sense, persisted 24 h after maximal isotonic eccentric training, revealing that neuromuscular functional outputs were affected by muscle fatigue and muscle damage. Conversely, force fluctuation and stability during the balance tasks were only affected by muscle fatigue since fully recovered was observed 24 h following isotonic eccentric exercise.
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Affiliation(s)
- Carolina Vila-Chã
- Laboratory for the Assessment of Sports Performance, Physical Exercise and Health (Labmov), Polytechnic of Guarda, Guarda, Portugal
- Research Center in Sports Sciences, Health Sciences, and Human Development, Vila Real, Portugal
| | - Antonio Bovolini
- Laboratory for the Assessment of Sports Performance, Physical Exercise and Health (Labmov), Polytechnic of Guarda, Guarda, Portugal
- Research Center in Sports Sciences, Health Sciences, and Human Development, Vila Real, Portugal
| | - Cristiana Francisco
- Laboratory for the Assessment of Sports Performance, Physical Exercise and Health (Labmov), Polytechnic of Guarda, Guarda, Portugal
| | - Ana R. Costa-Brito
- Laboratory for the Assessment of Sports Performance, Physical Exercise and Health (Labmov), Polytechnic of Guarda, Guarda, Portugal
| | - Cláudia Vaz
- Laboratory for the Assessment of Sports Performance, Physical Exercise and Health (Labmov), Polytechnic of Guarda, Guarda, Portugal
| | - María Rua-Alonso
- Laboratory for the Assessment of Sports Performance, Physical Exercise and Health (Labmov), Polytechnic of Guarda, Guarda, Portugal
- Research Center in Sports Sciences, Health Sciences, and Human Development, Vila Real, Portugal
- Performance and Health Group, Department of Physical Education and Sport, Faculty of Sports Sciences and Physical Education, University of A Coruna, A Coruña, Spain
| | | | - Taian Vieira
- Laboratorio di Ingegneria del Sistema Neuromuscolare (LISiN), Dipartimento di Elettronica e Telecomunicazioni, Politecnico di Torino, Turin, Italy
- PoliToBIOMed Lab, Politecnico di Torino, Turin, Italy
| | - Goncalo V. Mendonca
- Neuromuscular Research Laboratory, Faculdade de Motricidade Humana, Universidade de Lisboa, Lisbon, Portugal
- Interdisciplinary Center for the Study of Human Performance (CIPER), Faculdade de Motricidade Humana, Universidade de Lisboa, Lisbon, Portugal
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Nuzzo JL, Pinto MD, Nosaka K. Overview of muscle fatigue differences between maximal eccentric and concentric resistance exercise. Scand J Med Sci Sports 2023; 33:1901-1915. [PMID: 37269142 DOI: 10.1111/sms.14419] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 05/15/2023] [Accepted: 05/22/2023] [Indexed: 06/04/2023]
Abstract
Since the 1970s, researchers have studied a potential difference in muscle fatigue (acute strength loss) between maximal eccentric (ECCmax ) and concentric (CONmax ) resistance exercise. However, a clear answer to whether such a difference exists has not been established. Therefore, the aim of our paper was to overview methods and results of studies that compared acute changes in muscle strength after bouts of ECCmax and CONmax resistance exercise. We identified 30 relevant studies. Participants were typically healthy men aged 20-40 years. Exercise usually consisted of 40-100 isokinetic ECCmax and CONmax repetitions of the knee extensors or elbow flexors. Both ECCmax and CONmax exercise caused significant strength loss, which plateaued and rarely exceeded 60% of baseline, suggesting strength preservation. In upper-body muscles, strength loss at the end of ECCmax (31.4 ± 20.4%) and CONmax (33.6 ± 17.5%) exercise was similar, whereas in lower-body muscles, strength loss was less after ECCmax (13.3 ± 12.2%) than CONmax (39.7 ± 13.3%) exercise. Muscle architecture and daily use of lower-body muscles likely protects lower-body muscles from strength loss during ECCmax exercise. We also reviewed seven studies on muscle fatigue during coupled ECCmax -CONmax exercise and found similar strength loss in the ECC and CON phases. We also found evidence from three studies that more ECC than CON repetitions can be completed at equal relative loads. These results indicate that muscle fatigue may manifest differently between ECCmax and CONmax resistance exercise. An implication of the results is that prescriptions of ECC resistance exercise for lower-body muscles should account for greater fatigue resilience of these muscles compared to upper-body muscles.
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Affiliation(s)
- James L Nuzzo
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia
| | - Matheus D Pinto
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia
| | - Kazunori Nosaka
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia
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27
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Baxter BA, Baross AW, Ryan DJ, Wright BH, Kay AD. The acute and repeated bout effects of multi-joint eccentric exercise on physical function and balance in older adults. Eur J Appl Physiol 2023; 123:2131-2143. [PMID: 37217609 PMCID: PMC10492690 DOI: 10.1007/s00421-023-05226-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 05/10/2023] [Indexed: 05/24/2023]
Abstract
PURPOSE Eccentric muscle actions generate high levels of force at a low metabolic cost, making them a suitable training modality to combat age-related neuromuscular decline. The temporary muscle soreness associated with high intensity eccentric contractions may explain their limited use in clinical exercise prescription, however any discomfort is often alleviated after the initial bout (repeated bout effect). Therefore, the aims of the present study were to examine the acute and repeated bout effects of eccentric contractions on neuromuscular factors associated with the risk of falling in older adults. METHODS Balance, functional ability [timed up-and-go and sit-to-stand], and lower-limb maximal and explosive strength were measured in 13 participants (67.6 ± 4.9 year) pre- and post-eccentric exercise (0, 24, 48, and 72 hr) in Bout 1 and 14 days later in Bout 2. The eccentric exercise intervention was performed on an isokinetic unilateral stepper ergometer at 50% of maximal eccentric strength at 18 step‧min-1 per limb for 7 min (126 steps per limb). Two-way repeated measures ANOVAs were conducted to identify any significant effects (P ≤ 0.05). RESULTS Eccentric strength significantly decreased (- 13%) in Bout 1 at 24 hr post-exercise; no significant reduction was observed at any other time-point after Bout 1. No significant reductions occurred in static balance or functional ability at any time-point in either bout. CONCLUSION Submaximal multi-joint eccentric exercise results in minimal disruption to neuromuscular function associated with falls in older adults after the initial bout.
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Affiliation(s)
- Brett A Baxter
- Centre for Physical Activity and Life Sciences, Faculty of Art, Science and Technology, University of Northampton, Northampton, NN1 5PH, UK.
| | - Anthony W Baross
- Centre for Physical Activity and Life Sciences, Faculty of Art, Science and Technology, University of Northampton, Northampton, NN1 5PH, UK
| | - Declan J Ryan
- Centre for Physical Activity and Life Sciences, Faculty of Art, Science and Technology, University of Northampton, Northampton, NN1 5PH, UK
| | - Ben H Wright
- Centre for Physical Activity and Life Sciences, Faculty of Art, Science and Technology, University of Northampton, Northampton, NN1 5PH, UK
| | - Anthony D Kay
- Centre for Physical Activity and Life Sciences, Faculty of Art, Science and Technology, University of Northampton, Northampton, NN1 5PH, UK
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Gómez EM, Atef H, Elsayed SH, Zakaria HM, Navarro MP, Sulé EM. Effects of high-intensity interval training with an eccentric hamstring exercise program in futsal players: A randomized controlled trial. Medicine (Baltimore) 2023; 102:e34626. [PMID: 37543767 PMCID: PMC10402967 DOI: 10.1097/md.0000000000034626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/07/2023] Open
Abstract
BACKGROUND Physiotherapy protocols based on high-intensity interval training (HIIT) or eccentric hamstring exercises like Nordic Curl (NC) have been scarcely studied in futsal players. The objective of this study was to compare the effectiveness of a HIIT combined with an NC exercise program versus a HIIT-only program in futsal players. METHODS Twenty-one futsal players were divided into (1) HIIT + NC group (n = 11, mean age = 21.55 [4.25]); and (2) HIIT group (n = 10, mean age = 20.90 [1.29]). The HIIT + NC group performed a HIIT circuit combined with 3 sets of 10 NC repetitions for 4 weeks, while the HIIT group performed the same protocol without NC exercise. Body mass index, intermittent work performance, vertical jump performance without and with arms, isometric strength of quadriceps and hamstrings, and the isometric hamstrings/quadriceps (H/Q) ratio, were assessed before and after the interventions. RESULTS The HIIT + NC group and the HIIT group showed a significant improvement in intermittent work performance after the intervention (P = .04 and P = .01, respectively). Also, both groups showed a trend of increasing quadriceps and hamstring isometric strength, although no significant changes were found (P > .05). In addition, neither the HIIT + NC protocol nor the HIIT protocol was sufficient to yield changes in body mass index nor to improve the vertical jump performance (P > .05). CONCLUSION Both an isolated HIIT protocol and HIIT in combination with NC exercise improved intermittent work performance in futsal players. The present study's findings may guide futsal players' physical preparation and injury prevention programs.
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Affiliation(s)
- Elena Muñoz Gómez
- Department of Physiotherapy, Faculty of Physiotherapy, University of Valencia, Valencia, Spain
| | - Hady Atef
- School of Allied Health Professions, Keele University, Staffordshire, United Kingdom
- Department of Physical Therapy for Cardiovascular/Respiratory Disorders and Geriatrics, Faculty of Physical Therapy, Cairo University, Cairo, Egypt
| | - Shereen Hamed Elsayed
- Department of Rehabilitation Sciences, Faculty of Health and Rehabilitation Sciences, Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia
| | - Hoda M Zakaria
- Department of Physical Therapy for Neurology, College of Physical Therapy, Cairo University, Cairo, Egypt
| | - Miguel Pérez Navarro
- Department of Physiotherapy, Faculty of Physiotherapy, University of Valencia, Valencia, Spain
| | - Elena Marqués Sulé
- Physiotherapy in Motion, Multi-Speciality Research Group (PTinMOTION), University of Valencia, Valencia, Spain
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Krzysztofik M, Wilk M, Kolinger D, Pisz A, Świtała K, Petruzela J, Stastny P. Acute Effects of Supra- and High-Loaded Front Squats on Mechanical Properties of Lower-Limb Muscles. Sports (Basel) 2023; 11:148. [PMID: 37624128 PMCID: PMC10459263 DOI: 10.3390/sports11080148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 07/29/2023] [Accepted: 08/01/2023] [Indexed: 08/26/2023] Open
Abstract
Knowledge about the acute effects of supramaximal-loaded resistance exercises on muscle mechanical properties is scarce. Therefore, this study aimed to examine changes in dominant limb biceps femoris and vastus lateralis oscillation frequency and stiffness before and after high- and supramaximal-loaded front squats. Nineteen male handball players participated in the experimental session with a barbell front squat 1RM. The first set was performed at 70% of the 1RM for four repetitions, and the second and third sets were performed at 90%1RM in an eccentric-concentric or an eccentric-only manner at 120% of the 1RM for three repetitions. The handheld myometer was used for the measurement of the biceps femoris and vastus lateralis stiffness and the oscillation frequency of the dominant limb 5 min before and at the 5th and 10th min after front squats. A two-way ANOVA neither indicated a statistically significant interaction (p = 0.335; η2 = 0.059 and p = 0.103; η2 = 0.118), the main effect of a condition (p = 0.124; η2 = 0.126 and p = 0.197; η2 = 0.091), nor the main effect of the time point (p = 0.314; η2 = 0.06 and p = 0.196; η2 = 0.089) for vastus lateralis and biceps femoris stiffness. However, there was a statistically significant interaction (F = 3.516; p = 0.04; η2 = 0.163) for vastus lateralis oscillation frequency. The post hoc analysis showed a significantly higher vastus lateralis oscillation frequency at POST (p = 0.037; d = 0.29) and POST_10 (p = 0.02; d = 0.29) compared to PRE during the SUPRA condition. Moreover, Friedman's test indicated statistically significant differences in biceps femoris oscillation frequency (test = 15.482; p = 0.008; Kendall's W = 0.163). Pairwise comparison showed a significantly lower biceps femoris oscillation frequency in POST (p = 0.042; d = 0.31) and POST_10 (p = 0.015; d = 0.2) during the HIGH condition compared to that in the corresponding time points during the SUPRA condition. The results of this study indicate that the SUPRA front squats, compared to the high-loaded ones, cause a significant increase in biceps femoris and vastus lateralis oscillation frequency.
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Affiliation(s)
- Michal Krzysztofik
- Department of Sport Games, Faculty of Physical Education and Sport, Charles University in Prague, 110 00 Prague, Czech Republic; (M.W.)
- Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education, 40-065 Katowice, Poland
| | - Michal Wilk
- Department of Sport Games, Faculty of Physical Education and Sport, Charles University in Prague, 110 00 Prague, Czech Republic; (M.W.)
- Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education, 40-065 Katowice, Poland
| | - Dominik Kolinger
- Department of Sport Games, Faculty of Physical Education and Sport, Charles University in Prague, 110 00 Prague, Czech Republic; (M.W.)
| | - Anna Pisz
- Department of Sport Games, Faculty of Physical Education and Sport, Charles University in Prague, 110 00 Prague, Czech Republic; (M.W.)
| | - Katarzyna Świtała
- Faculty of Physical Education, Gdansk University of Physical Education and Sport, 80-336 Gdańsk, Poland;
| | - Jan Petruzela
- Department of Sport Games, Faculty of Physical Education and Sport, Charles University in Prague, 110 00 Prague, Czech Republic; (M.W.)
| | - Petr Stastny
- Department of Sport Games, Faculty of Physical Education and Sport, Charles University in Prague, 110 00 Prague, Czech Republic; (M.W.)
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Lim CL, Keong NLS, Yap MMC, Tan AWK, Tan CH, Lim WS. The effects of community-based exercise modalities and volume on musculoskeletal health and functions in elderly people. Front Physiol 2023; 14:1227502. [PMID: 37492640 PMCID: PMC10363600 DOI: 10.3389/fphys.2023.1227502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 06/26/2023] [Indexed: 07/27/2023] Open
Abstract
The effects of different muscle loading exercise (MLEX) modes and volume on musculoskeletal health is not well-studied in older populations. Aim: Therefore, this study aimed to compare the effects of community-based MLEX modalities and volume on musculoskeletal health in elderly people. Methods: Elderly men (n = 86) and women (n = 170), age 50-82 years old, were assigned to the sedentary (SE, n = 60), muscle strengthening exercise (MSE, n = 71), aerobic exercise (AE, n = 62) and Tai Chi exercise (TCE, n = 63) groups, based on > 2 years of exercise history. Exercise volume was compared between "Minimum" ("Min" < 60 min/week), "Low" (60-120 min/week). "Moderate" (121-239 min/week) and "High" (240-720 min/week) volumes. Results: All three modes of MLEX were associated with lower percentage of body fat (BF%) and higher percentage of lean body mass (LBM%, p = 0.003 main effect of group, and p = 0.002 main effect of volume for both BF% and LBM%), but not with higher bone mineral density (BMD, total body, lumbar spine, total hip and neck of femur), than SE. TCE had a distinct advantage in trunk flexibility (p = 0.007 with MSE, p = 0.02 with AE, and p = 0.01 with SE), and both TCE (p = 0.03) and AE (p = 0.03) performed better than SE in the one-leg stand balance test. Isometric strength and throwing speed and peak power with a 2 kg power ball were higher in the MLEX than SE groups (p = 0.01), in the ranking order of MSE, AE and TCE. However, there was no difference in handgrip strength performance between the MLEX groups, which performed better than the SE participants. Accumulating >120 min/week of MLEX can promote body composition health and muscle functions, but 60 min/week of MSE alone may have equal or better outcomes in these parameters. Conclusion: Community-based MLEX classes may be used to mitigate age-related chronic disease that are associated with body composition and muscular functions.
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Affiliation(s)
- Chin Leong Lim
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | | | - Margaret Mei Chan Yap
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Alvin Wai Kit Tan
- Department of Endocrinology, Tan Tock Seng Hospital, National Healthcare Group, Singapore, Singapore
| | - Cher Heng Tan
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
- Department of Diagnostic Radiology, Tan Tock Seng Hospital, National Healthcare Group, Singapore, Singapore
| | - Wee Shiong Lim
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
- Department of Geriatric Medicine, Institute of Geriatrics and Active Aging, Tan Tock Seng Hospital, Singapore, Singapore
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Venter S, Stapley PJ, Walsh JA, Cheung R, Sreenivasa M. Analysing the contributions of lower limb muscles to eccentric cycling using musculoskeletal modeling and simulation. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2023; 2023:1-4. [PMID: 38083365 DOI: 10.1109/embc40787.2023.10340580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
Eccentric (ECC) cycling, compared to traditional concentric cycling, has been shown to improve muscle strength and neuromuscular control at a lower metabolic cost. Despite the popularity of this exercise in the sports and rehabilitation contexts, there is a gap in our knowledge of which muscles are behaving eccentrically during ECC cycling. To this end, we used a musculoskeletal model and computer simulations to calculate joint kinematics and muscle lengths during ECC cycling. Movements were recorded using 3D motion capture technology while cycling eccentrically on a custom-built semi-recumbent ergometer. The software Opensim was used to calculate joint kinematics and muscle lengths from recorded movements. We found that among the primary knee extensors, it was predominantly the Vastii muscles that acted eccentrically in the ECC cycling phase, with other lower limb muscles showing mixed eccentric/concentric activation. Additionally, the muscle force-length and force-velocity factors in the ECC phase suggest that changes to the participant's pose and pedaling speed may elicit larger active muscle forces. Our work provides an interesting application of musculoskeletal modeling to ECC cycling, and an alternative way to help understand in-vivo muscle mechanics during this activity.
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Younes-Egana O, Mielgo-Ayuso J, M. Stojanović MD, Bird SP, Calleja-González J. Effectiveness of Eccentric Overload Training in Basketball Players: A Systematic Review. J Hum Kinet 2023; 87:243-257. [PMID: 37559764 PMCID: PMC10407313 DOI: 10.5114/jhk/167469] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 04/24/2023] [Indexed: 08/11/2023] Open
Abstract
Several studies have confirmed the efficacy of flywheel eccentric overload training in order to improve or increase muscle volume and strength, as well as several performance-related fitness attributes, but to date, there are no studies that have reviewed the effects of these training methods in basketball. Therefore, the present systematic review aimed to collect the updated information about the influence of flywheel training on performance of basketball players. A search in four electronic databases (PubMed, SCOPUS, Web of Science, and Google Scholar) was conducted up to November 20, 2022. Articles were selected as valid for review if: (i) they were an experimental trial published in English; (ii) participants were basketball players without illnesses or injuries, and (iii) a rotational inertial overload method was used as a performance-dependent variable. A total of 93 articles were found. After filtering procedures, only seven studies were considered in this systematic review. In the selected studies, 203 participants were included, 58 females and 145 males. Focusing on basketball related performance variables, all the studies included the countermovement jump (CMJ), while five included sprinting and a change of direction test (COD). The results showed an improvement in performance-related variables associated with basketball (sprint, CMJ, and COD) through the use of inertial methods. Improvements were reported in professional, semi-professional and amateur players as well as both male and female players. However, given the low number of studies, additional investigations on this topic are warranted before a "clear picture" can be drawn concerning the effects of flywheel eccentric overload training in basketball players.
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Affiliation(s)
| | | | | | - Stephen P. Bird
- School of Health and Medical Sciences, University of Southern Queensland, Ipswich, Australia
| | - Julio Calleja-González
- Faculty of Education and Sport, University of the Basque Country (UPV/EHU), Vitoria, Spain
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Bianchi M, Anderson L, Brownlee TE, Bossi L, Beato M. The effect of two sessions of combined jump and sprint training per week on fitness parameters in soccer players. A randomized controlled trial. Biol Sport 2023; 40:699-706. [PMID: 37398964 PMCID: PMC10286599 DOI: 10.5114/biolsport.2023.119287] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 07/18/2022] [Accepted: 08/02/2022] [Indexed: 02/23/2024] Open
Abstract
This study aimed to investigate the effect of a combined jump and sprint training program, two sessions a week for 6 weeks, on sprinting, change of directions (COD) and jumping performance in semi-professional soccer players. Twenty soccer players were enrolled in this randomized controlled trial (age 20 ± 2 years, body mass 74.3 ± 5.9 kg). Players were randomized into two groups such as training group (TG, n = 10 players) or control group (CG, n = 10 players). Physical tests were performed before and after 6 weeks of training such as sprint 10 m, sprint 30 m, 505-COD test and standing long jump (LJ). The two groups performed the same training except for the combined jump and sprint training performed twice a week by TG. After 6 weeks of training, between-group analysis reported statistical difference in favor of the TG in sprint 10 m (p = 0.015, η2 = 0.295, large), sprint 30 m (p < 0.001, η2 = 0.599, large), in 505-COD (p = 0.026, η2 = 0.154, large), and LJ (p = 0.025, η2 = 0.027, small). These data indicate that combined sprint and jump training, when performed twice a week, for the duration of 6 weeks, in addition to the regular team training, can improve specific physical performance in male soccer players. This study has shown that a volume increment of 10% after 3 weeks of training can be a suitable training dose progression and that a combination of 64-70 jumps and 675-738 m of sprinting training per session can yield benefits in sprint, COD and jump performance.
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Affiliation(s)
- Mattia Bianchi
- School of Health and Sports Science, University of Suffolk, Ipswich, United Kingdom
| | - Liam Anderson
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Thomas E Brownlee
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Lorenzo Bossi
- School of Health and Sports Science, University of Suffolk, Ipswich, United Kingdom
| | - Marco Beato
- School of Health and Sports Science, University of Suffolk, Ipswich, United Kingdom
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Nuzzo JL, Pinto MD, Nosaka K. Connective Adaptive Resistance Exercise (CARE) Machines for Accentuated Eccentric and Eccentric-Only Exercise: Introduction to an Emerging Concept. Sports Med 2023; 53:1287-1300. [PMID: 37097413 PMCID: PMC10127187 DOI: 10.1007/s40279-023-01842-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2023] [Indexed: 04/26/2023]
Abstract
Eccentric resistance exercise emphasizes active muscle lengthening against resistance. In the past 15 years, researchers and practitioners have expressed considerable interest in accentuated eccentric (i.e., eccentric overload) and eccentric-only resistance exercise as strategies for enhancing performance and preventing and rehabilitating injuries. However, delivery of eccentric resistance exercise has been challenging because of equipment limitations. Previously, we briefly introduced the concept of connected adaptive resistance exercise (CARE)-the integration of software and hardware to provide a resistance that adjusts in real time and in response to the individual's volitional force within and between repetitions. The aim of the current paper is to expand this discussion and explain the potential for CARE technology to improve the delivery of eccentric resistance exercise in various settings. First, we overview existing resistance exercise equipment and highlight its limitations for delivering eccentric resistance exercise. Second, we describe CARE and explain how it can accomplish accentuated eccentric and eccentric-only resistance exercise in a new way. We supplement this discussion with preliminary data collected with CARE technology in laboratory and non-laboratory environments. Finally, we discuss the potential for CARE technology to deliver eccentric resistance exercise for various purposes, e.g., research studies, rehabilitation programs, and home-based or telehealth interventions. Overall, CARE technology appears to permit completion of eccentric resistance exercise feasibly in both laboratory and non-laboratory environments and thus has implications for researchers and practitioners in the fields of sports medicine, physiotherapy, exercise physiology, and strength and conditioning. Nevertheless, formal investigations into the impact of CARE technology on participation in eccentric resistance exercise and clinical outcomes are still required.
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Affiliation(s)
- James L Nuzzo
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia.
| | - Matheus D Pinto
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia
| | - Kazunori Nosaka
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia
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Jarosz J, Królikowska P, Matykiewicz P, Aschenbrenner P, Ewertowska P, Krzysztofik M. Effects of Flywheel vs. Free-Weight Squats and Split Squats on Jumping Performance and Change of Direction Speed in Soccer Players. Sports (Basel) 2023; 11:124. [PMID: 37505611 PMCID: PMC10386668 DOI: 10.3390/sports11070124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 06/13/2023] [Accepted: 06/21/2023] [Indexed: 07/29/2023] Open
Abstract
The objective of this study was to compare (i) The effects of a flywheel and free-weight resistance training program; and (ii) The effects of performing lateral and frontal split squats as part of a flywheel-resistance training program on jumping performance, the 5-0-5 change of direction test time, and the one-repetition maximum (1RM) back squat in soccer players. Twenty-four male amateur soccer players participated in this study and were randomly and equally assigned to one of three different test groups: forward split-squat group (FSQ); lateral split-squat group (LSQ); and free-weight training group (TRAD). Athletes in the FSQ group performed a squat and a forward split squat on a flywheel device, while those in the LSQ group performed a squat and a lateral split squat (instead of a forward split squat) on a flywheel device. Each training lasted 4 weeks. The main finding was that all training groups, such as TRAD, FSQ, and LSQ, significantly improved broad jump length (p = 0.001; effect size [ES] = 0.36), 5-0-5 COD time with a turn on the dominant limb (p = 0.038; ES = 0.49), and 1RM back squat (p = 0.001; ES = 0.4). In turn, both flywheel-resistance training groups (FSQ and LSQ) significantly improved their counter-movement jump height (p = 0.001; ES = 0.8 and p = 0.002; ES = 0.58; respectively) with no effect in the TRAD (p = 0.676; ES = 0.07) training group. Both free-weight and flywheel-resistance training lasting 4 weeks performed in-season contributed to significant improvement in 1RM back squat, broad jump performance, and 5-0-5 change of direction testing time, while flywheel-resistance training might be superior in counter-movement jump height enhancement in soccer players. Moreover, the manner in which split squats were performed was not a factor influencing the obtained results.
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Affiliation(s)
- Jakub Jarosz
- Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education, 40-065 Katowice, Poland
| | - Paulina Królikowska
- Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education, 40-065 Katowice, Poland
| | - Patryk Matykiewicz
- Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education, 40-065 Katowice, Poland
| | - Piotr Aschenbrenner
- Department of Biomechanics and Sports Engineering, Gdansk University of Physical Education and Sport, 80-336 Gdansk, Poland
| | - Paulina Ewertowska
- Division of Clinical Physiotherapy, Faculty of Physical Education, Gdansk University of Physical Education and Sport, 80-336 Gdańsk, Poland
| | - Michał Krzysztofik
- Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education, 40-065 Katowice, Poland
- Department of Sport Games, Faculty of Physical Education and Sport, Charles University in Prague, 110 00 Prague, Czech Republic
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Stojanović MDM, Andrić N, Mikić M, Vukosav N, Vukosav B, Zolog-Șchiopea DN, Tăbăcar M, Melinte RM. Effects of Eccentric-Oriented Strength Training on Return to Sport Criteria in Late-Stage Anterior Cruciate Ligament (ACL)-Reconstructed Professional Team Sport Players. MEDICINA (KAUNAS, LITHUANIA) 2023; 59:1111. [PMID: 37374316 DOI: 10.3390/medicina59061111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 06/01/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023]
Abstract
Background and Objectives: An effective post-injury training program is essential to regain performance and fulfill criteria for return to sport for team sport athletes following anterior cruciate ligament (ACL) reconstruction. The aim of this study was to compare the effects of 6 weeks of eccentric-oriented strength training vs. traditional strength training during the late-stage ACL-rehab phase on leg strength and vertical and horizontal jumping performance in professional team sport athletes. Materials and Methods: Twenty-two subjects (14 males, 8 females, age 19.9 ± 4.4 years, mass 77.4 ± 15.6 kg, height 182.4 ± 11.7 cm) (mean ± SD) with a unilateral reconstructed ACL (BTB graft) were included in the study. All participants enrolled in the same rehabilitation protocol prior to the training study. Players were randomly assigned to an experimental (ECC: n = 11, age 21.8 ± 4.6 years, mass 82.7 ± 16.6 kg, height 185.4 ± 12.2 cm), and a control group (CON: n = 11, age 19.1 ± 2.1 years, mass 76.6 ± 16.5 kg, height 182.5 ± 10.2 cm). Both groups underwent an equivolumed rehabilitation program, with the only difference being in strength training, which consisted of flywheel training vs. traditional strength training for the experimental and control groups, respectively. Testing was organized before and after the 6-week training programs and included isometric semi-squat tests (ISOSI-injured and ISOSU-uninjured legs), vertical jump tests (CMJ), single-leg vertical jump tests (SLJI-injured and SLJU-uninjured legs), single-leg hop tests (SLHI-injured and SLHU-uninjured legs), and triple hop tests (TLHI-injured and TLHU-uninjured legs). In addition, limb symmetry indexes were calculated for the isometric semi-squat (ISOSLSI) test, the single-leg vertical jump (SLJLSI), and the hop (SLHLSI) tests, as well as the triple-leg hop (THLLSI) test. Results: Main effects of time across training were observed for all dependent variables (posttest > pretest, p < 0.05). Significant group-by-time interactions were found for ISOSU (p < 0.05, ES = 2.51, very large), ISOSI (p < 0.05, ES = 1.78, large), CMJ (p < 0.05, ES = 2.23, very large), SLJI (p < 0.05, ES = 1.48, large), SLHI (p < 0.05, ES = 1.83, large), and TLHI (p < 0.05, ES = 1.83, large). Conclusions: This study suggests that eccentric-oriented strength training in late-stage ACL recovery, undertaken twice or three times weekly for 6 weeks, results in better outcomes than traditional strength training in leg strength, vertical jump ability, and single and triple hop tests with injured legs in professional team sport athletes. It seems that flywheel strength training can be recommended in late-stage ACL recovery for professional team sport athletes in order to regain recommended performance outcome levels faster.
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Affiliation(s)
- Marko D M Stojanović
- Training Expertise Lab, Faculty of Sport and Physical Education, University of Novi Sad, 21000 Novi Sad, Serbia
- Faculty of Sport and Physical Education, University of Novi Sad, 21000 Novi Sad, Serbia
| | - Nikola Andrić
- Training Expertise Lab, Faculty of Sport and Physical Education, University of Novi Sad, 21000 Novi Sad, Serbia
- Faculty of Sport and Physical Education, University of Novi Sad, 21000 Novi Sad, Serbia
| | - Mladen Mikić
- Training Expertise Lab, Faculty of Sport and Physical Education, University of Novi Sad, 21000 Novi Sad, Serbia
- Faculty of Sport and Physical Education, University of Novi Sad, 21000 Novi Sad, Serbia
| | - Nikola Vukosav
- Clinic for Orthopedic Surgery and Traumatology, Clinical Center of Vojvodina, 21000 Novi Sad, Serbia
| | - Borko Vukosav
- Sports Medicine Department, Medical Clinic "ST Medicina", 21000 Novi Sad, Serbia
| | - Dan-Nicolae Zolog-Șchiopea
- Orthopedic Department, Puls Hospital of Regina Maria Hospital, 540136 Targu Mures, Romania
- Orthopedic Surgery and Traumatology Department, Humanitas Hospital, 400001 Cluj Napoca, Romania
| | - Mircea Tăbăcar
- Orthopedic Department, Puls Hospital of Regina Maria Hospital, 540136 Targu Mures, Romania
| | - Răzvan Marian Melinte
- Orthopedic Department, Puls Hospital of Regina Maria Hospital, 540136 Targu Mures, Romania
- Orthopedic Surgery and Traumatology Department, Humanitas Hospital, 400001 Cluj Napoca, Romania
- Fizionova Reahabilitation, 540136 Targu Mures, Romania
- Orthopedic Surgery and Traumatology Department, Dimitrie Cantemir University, 540136 Targu Mures, Romania
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37
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Bright TE, Handford MJ, Mundy P, Lake J, Theis N, Hughes JD. Building for the Future: A Systematic Review of the Effects of Eccentric Resistance Training on Measures of Physical Performance in Youth Athletes. Sports Med 2023; 53:1219-1254. [PMID: 37097414 PMCID: PMC10185653 DOI: 10.1007/s40279-023-01843-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/17/2023] [Indexed: 04/26/2023]
Abstract
BACKGROUND Eccentric resistance training is recognised as an effective stimulus for enhancing measures of muscular strength and power in adult populations; however, its value in youth athletes is currently not well understood. OBJECTIVE The aim of this systematic review was to critically appraise the effects of eccentric resistance training on measures of physical performance (i.e. muscular strength, jump, sprint and change of direction) in youth athletes 18 years of age and under. METHODS Original journal articles published between 1950 and June 2022 were retrieved from electronic search engines of PubMed, SPORTDiscus and Google Scholar's advanced search option. Full journal articles investigating the acute and chronic effects of eccentric resistance training on measures of physical performance in youth athletes (i.e. a person 18 years of age or under who competes in sport) were included. The methodological quality and bias of each study were assessed prior to data extraction using a modified Downs and Black checklist. RESULTS The search yielded 749 studies, of which 436 were duplicates. Three-hundred studies were excluded based upon title and abstract review and a further 5 studies were removed following the modified Downs and Black checklist. An additional 14 studies were identified during backward screening. Accordingly, 22 studies were included in our systematic review. The Nordic hamstring exercise and flywheel inertial training were the most frequently used eccentric resistance training methods in youth athletes. Improvements in physical performance following the Nordic hamstring exercise are dependent upon an increase in the breakpoint angle, rather than training volume (sets and repetitions), and are further elevated with the addition of hip extension exercises or high-speed running. A minimum of 3 familiarisation trials is necessary to elicit meaningful adaptations following flywheel inertial training. Furthermore, an emphasis should be placed upon decelerating the rotating flywheel during the final one to two thirds of the eccentric phase, rather than gradually throughout the entire eccentric phase. CONCLUSIONS The findings of this systematic review support the inclusion of eccentric resistance training in youth athletes to improve measures of muscular strength, jump, sprint and change of direction performance. The current eccentric resistance training methods are predominantly limited to the Nordic hamstring exercise and flywheel inertial training; however, the efficacy of accentuated eccentric loading to improve jump performance warrants attention in future investigations.
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Affiliation(s)
- Thomas E. Bright
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, UK
- School of Sport and Exercise, University of Gloucestershire, Gloucester, UK
- School of Sport, Health and Wellbeing, Plymouth Marjon University, Derriford Rd, Plymouth, PL6 8BH UK
| | - Matthew J. Handford
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, UK
- School of Sport and Exercise, University of Gloucestershire, Gloucester, UK
| | | | - Jason Lake
- Department of Sport and Exercise Sciences, Chichester University, Chichester, UK
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA Australia
| | - Nicola Theis
- School of Sport and Exercise, University of Gloucestershire, Gloucester, UK
| | - Jonathan D. Hughes
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, UK
- School of Sport and Exercise, University of Gloucestershire, Gloucester, UK
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de Carvalho MR, Duarte EF, Mendonça MLM, de Morais CS, Ota GE, Gaspar-Junior JJ, de Oliveira Filiú WF, Damatto FC, Okoshi MP, Okoshi K, Oliveira RJ, Martinez PF, de Oliveira-Junior SA. Effects of Creatine Supplementation on the Myostatin Pathway and Myosin Heavy Chain Isoforms in Different Skeletal Muscles of Resistance-Trained Rats. Nutrients 2023; 15:2224. [PMID: 37432386 DOI: 10.3390/nu15092224] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 04/25/2023] [Accepted: 04/26/2023] [Indexed: 07/12/2023] Open
Abstract
Creatine has been used to maximize resistance training effects on skeletal muscles, including muscle hypertrophy and fiber type changes. This study aimed to evaluate the impact of creatine supplementation on the myostatin pathway and myosin heavy chain (MyHC) isoforms in the slow- and fast-twitch muscles of resistance-trained rats. Twenty-eight male Wistar rats were divided into four groups: a sedentary control (Cc), sedentary creatine supplementation (Cr), resistance training (Tc), and resistance training combined with creatine supplementation (Tcr). Cc and Tc received standard commercial chow; Cr and Tcr received a 2% creatine-supplemented diet. Tc and Tcr performed a resistance training protocol on a ladder for 12 weeks. Morphology, MyHC isoforms, myostatin, follistatin, and ActRIIB protein expressions were analyzed in soleus and white gastrocnemius portion samples. The results were analyzed using two-way ANOVA and Tukey's test. Tc and Tcr exhibited higher performance than their control counterparts. Resistance training increased the ratio between muscle and body weight, the cross-sectional area, as well as the interstitial collagen fraction. Resistance training alone increased MyHC IIx and follistatin while reducing myostatin (p < 0.001) and ActRIIB (p = 0.040) expressions in the gastrocnemius. Resistance training induced skeletal muscle hypertrophy and interstitial remodeling, which are more evident in the gastrocnemius muscle. The effects were not impacted by creatine supplementation.
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Affiliation(s)
- Marianna Rabelo de Carvalho
- Graduate Program in Health and Development in the Midwestern Region, Federal University of Mato Grosso do Sul (UFMS), Campo Grande 79070-900, MS, Brazil
| | - Ellen Fernandes Duarte
- Graduate Program in Health and Development in the Midwestern Region, Federal University of Mato Grosso do Sul (UFMS), Campo Grande 79070-900, MS, Brazil
| | - Maria Lua Marques Mendonça
- Graduate Program in Health and Development in the Midwestern Region, Federal University of Mato Grosso do Sul (UFMS), Campo Grande 79070-900, MS, Brazil
| | - Camila Souza de Morais
- Graduate Program in Health and Development in the Midwestern Region, Federal University of Mato Grosso do Sul (UFMS), Campo Grande 79070-900, MS, Brazil
| | - Gabriel Elias Ota
- Graduate Program in Health and Development in the Midwestern Region, Federal University of Mato Grosso do Sul (UFMS), Campo Grande 79070-900, MS, Brazil
| | - Jair José Gaspar-Junior
- Graduate Program in Health and Development in the Midwestern Region, Federal University of Mato Grosso do Sul (UFMS), Campo Grande 79070-900, MS, Brazil
| | - Wander Fernando de Oliveira Filiú
- Faculty of Pharmaceutical Sciences, Food and Nutrition, Federal University of Mato Grosso do Sul (UFMS), Campo Grande 79070-900, MS, Brazil
| | - Felipe Cesar Damatto
- Internal Medicine Department, Botucatu Medical School, Sao Paulo State University (UNESP), Botucatu 18618-687, SP, Brazil
| | - Marina Politi Okoshi
- Internal Medicine Department, Botucatu Medical School, Sao Paulo State University (UNESP), Botucatu 18618-687, SP, Brazil
| | - Katashi Okoshi
- Internal Medicine Department, Botucatu Medical School, Sao Paulo State University (UNESP), Botucatu 18618-687, SP, Brazil
| | - Rodrigo Juliano Oliveira
- Graduate Program in Health and Development in the Midwestern Region, Federal University of Mato Grosso do Sul (UFMS), Campo Grande 79070-900, MS, Brazil
| | - Paula Felippe Martinez
- Graduate Program in Health and Development in the Midwestern Region, Federal University of Mato Grosso do Sul (UFMS), Campo Grande 79070-900, MS, Brazil
- Graduate Program in Movement Sciences, Federal University of Mato Grosso do Sul (UFMS), Campo Grande 79070-900, MS, Brazil
| | - Silvio Assis de Oliveira-Junior
- Graduate Program in Health and Development in the Midwestern Region, Federal University of Mato Grosso do Sul (UFMS), Campo Grande 79070-900, MS, Brazil
- Graduate Program in Movement Sciences, Federal University of Mato Grosso do Sul (UFMS), Campo Grande 79070-900, MS, Brazil
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Nuzzo JL, Pinto MD, Nosaka K, Steele J. The Eccentric:Concentric Strength Ratio of Human Skeletal Muscle In Vivo: Meta-analysis of the Influences of Sex, Age, Joint Action, and Velocity. Sports Med 2023; 53:1125-1136. [PMID: 37129779 DOI: 10.1007/s40279-023-01851-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/04/2023] [Indexed: 05/03/2023]
Abstract
For decades, researchers have observed that eccentric (ECC) muscle strength is greater than concentric (CON) muscle strength. However, knowledge of the ECC:CON strength ratio is incomplete and might inform resistance exercise prescriptions. Our purposes were to determine the magnitude of the ECC:CON ratio of human skeletal muscle in vivo and explore if sex, age, joint actions/exercises, and movement velocity impact it. A total of 340 studies were identified through searches. It was possible to analyse 1516 ECC:CON ratios, aggregated from 12,546 individuals who made up 564 groups in 335 of the identified studies. Approximately 98% of measurements occurred on isokinetic machines. Bayesian meta-analyses were performed using log-ratios as response variables then exponentiated back to raw ratios. The overall main model estimate for the ECC:CON ratio was 1.41 (95% credible interval [CI] 1.38-1.44). The ECC:CON ratio was slightly less in men (1.38 [CI 1.34-1.41]) than women (1.47 [CI 1.43-1.51]), and greater in older adults (1.62 [CI 1.57-1.68]) than younger adults (1.39 [CI 1.36-1.42]). The ratio was similar between grouped upper-body (1.42 [CI 1.38-1.46]) and lower-body joint actions/exercises (1.40 [CI 1.37-1.44]). However, heterogeneity in the ratio existed across joint actions/exercises, with point estimates ranging from 1.32 to 2.61. The ECC:CON ratio was most greatly impacted by movement velocity, with a 0.20% increase in the ratio for every 1°/s increase in velocity. The results show that ECC muscle strength is ~ 40% greater than CON muscle strength. However, the ECC:CON ratio is greatly affected by movement velocity and to lesser extents age and sex. Differences between joint actions/exercises likely exist, but more data are needed to provide more precise estimates.
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Affiliation(s)
- James L Nuzzo
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia.
| | - Matheus D Pinto
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia
| | - Kazunori Nosaka
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia
| | - James Steele
- School of Sport, Health, and Social Sciences, Solent University, Southampton, UK
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40
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Spiering BA, Clark BC, Schoenfeld BJ, Foulis SA, Pasiakos SM. Maximizing Strength: The Stimuli and Mediators of Strength Gains and Their Application to Training and Rehabilitation. J Strength Cond Res 2023; 37:919-929. [PMID: 36580280 DOI: 10.1519/jsc.0000000000004390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
ABSTRACT Spiering, BA, Clark, BC, Schoenfeld, BJ, Foulis, SA, and Pasiakos, SM. Maximizing strength: the stimuli and mediators of strength gains and their application to training and rehabilitation. J Strength Cond Res 37(4): 919-929, 2023-Traditional heavy resistance exercise (RE) training increases maximal strength, a valuable adaptation in many situations. That stated, some populations seek new opportunities for pushing the upper limits of strength gains (e.g., athletes and military personnel). Alternatively, other populations strive to increase or maintain strength but cannot perform heavy RE (e.g., during at-home exercise, during deployment, or after injury or illness). Therefore, the purpose of this narrative review is to (a) identify the known stimuli that trigger gains in strength; (b) identify the known factors that mediate the long-term effectiveness of these stimuli; (c) discuss (and in some cases, speculate on) potential opportunities for maximizing strength gains beyond current limits; and (d) discuss practical applications for increasing or maintaining strength when traditional heavy RE cannot be performed. First, by conceptually deconstructing traditional heavy RE, we identify that strength gains are stimulated through a sequence of events, namely: giving maximal mental effort, leading to maximal neural activation of muscle to produce forceful contractions, involving lifting and lowering movements, training through a full range of motion, and (potentially) inducing muscular metabolic stress. Second, we identify factors that mediate the long-term effectiveness of these RE stimuli, namely: optimizing the dose of RE within a session, beginning each set of RE in a minimally fatigued state, optimizing recovery between training sessions, and (potentially) periodizing the training stimulus over time. Equipped with these insights, we identify potential opportunities for further maximizing strength gains. Finally, we identify opportunities for increasing or maintaining strength when traditional heavy RE cannot be performed.
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Affiliation(s)
- Barry A Spiering
- Military Performance Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - Brian C Clark
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, Ohio
- Department of Biomedical Sciences, Ohio University, Athens, Ohio; and
| | | | - Stephen A Foulis
- Military Performance Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - Stefan M Pasiakos
- Military Performance Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts
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Chen TCC, Kang HY, Tseng WC, Lin SC, Chan CW, Chen HL, Chou TY, Wang HH, Lau WY, Nosaka K. Muscle damage induced by maximal eccentric exercise of the elbow flexors after 3-week immobilization. Scand J Med Sci Sports 2023; 33:382-392. [PMID: 36427271 DOI: 10.1111/sms.14279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 11/06/2022] [Accepted: 11/21/2022] [Indexed: 11/27/2022]
Abstract
The present study investigated the effects of a 3-week immobilization (IM) on muscle damage induced by maximal eccentric exercise (MaxEC) to test the hypothesis that the IM would make muscles prone to muscle damage. Young healthy sedentary men were pseudo-randomly assigned to IM or control group (n = 12/group). Non-dominant arms of the IM group participants were immobilized at 90° elbow flexion by a cast for 21 days. All participants performed MaxEC consisting of five sets of six elbow flexor contractions by lowering a dumbbell set at 100% of pre-exercise maximal voluntary isometric contraction (MVC) strength of the non-dominant arm. This was performed at 2 days after the cast removal for the IM group. MVC torque, range of motion (ROM), muscle thickness (MT), muscle hardness, position sense (PS), and joint reaction angle (JRA) of the elbow flexors were measured at baseline, post-immobilization, and before, immediately after, and one to 5 days after MaxEC. The IM decreased MVC torque (-17 ± 2%), ROM (-2 ± 1%), MT (-7 ± 3%), and JRA (-12 ± 6%), and increased in muscle hardness (20 ± 6%) and PS (11 ± 2%) (p < 0.05). Changes in MVC (e.g., 2 days: -40 ± 5 vs. -30 ± 9%), ROM (2 days: -11 ± 2 vs. -9 ± 3%), muscle soreness (peak: 63 ± 22 vs. 48 ± 14 mm), plasma CK activity (peak: 7820 ± 4011 vs. 4980 ± 1363 IU/L), PS (maximal change: -23 ± 2 vs. -18 ± 3%), and JRA (maximal change: -37 ± 4 vs. -26 ± 3%) after MaxEC were greater (p < 0.05) for the IM than control group. These results supported the hypothesis and showed that the IM made the muscles more vulnerable to muscle damage induced by eccentric exercise.
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Affiliation(s)
- Trevor Chung-Ching Chen
- Department of Physical Education and Sport Sciences, National Taiwan Normal University, Taipei, Taiwan
| | - Hsing-Yu Kang
- Department of Physical Education and Sport Sciences, National Taiwan Normal University, Taipei, Taiwan
| | - Wei-Chin Tseng
- Department of Physical Education, University of Taipei, Taipei, Taiwan
| | - Shih-Che Lin
- Department of Physical Education, National Pingtung University, Pingtung, Taiwan
| | - Chuan-Wei Chan
- Department of Physical Education and Sport Sciences, National Taiwan Normal University, Taipei, Taiwan
| | - Hsin-Lian Chen
- Department of Physical Education, Health and Recreation, National Chiayi University, Chiayi, Taiwan
| | - Tai-Ying Chou
- Department of Athletic Performance, National Taiwan Normal University, Taipei, Taiwan
| | - Hung-Hao Wang
- Department of Physical Education and Sport Sciences, National Taiwan Normal University, Taipei, Taiwan
| | - Wing Yin Lau
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
| | - Kazunori Nosaka
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
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Buonsenso A, Centorbi M, Iuliano E, Di Martino G, Della Valle C, Fiorilli G, Calcagno G, di Cagno A. A Systematic Review of Flywheel Training Effectiveness and Application on Sport Specific Performances. Sports (Basel) 2023; 11:sports11040076. [PMID: 37104150 PMCID: PMC10144427 DOI: 10.3390/sports11040076] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/22/2023] [Accepted: 03/24/2023] [Indexed: 04/03/2023] Open
Abstract
The objective of this systematic review was to examine the effectiveness of flywheel training, which allows for the replication of specific sports movements, overloading both the concentric and eccentric phases. Inclusion criteria were injury prevention outcomes; ability in terms of strength, power, sprinting, jumping and change of direction; competitive athletes; and RCTs. Exclusion criteria were a lack of a control group and lack of baseline and/or follow-up data. The databases used were Web of Science, Scopus, PubMed, Cochrane Library, and Sage. The revised Cochrane risk-of-bias tool was used to assess the quality of the selected RCTs. The Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence was used. A PICOS (participants, intervention, comparators, study outcomes, and study design) approach was used to evaluate eligibility. A total of 21 RCTs with 8 to 54 participants in each study analyzed flywheel technology and its application in nine sports. The results showed that flywheel training is a good strategy to improve sports performance, providing variation in training methodologies and athletes’ adherence. Further studies are needed to define guidelines on training modality, weekly frequency, volume, and inertia load. Only a few studies have applied the flywheel device directly to overload specific multidirectional movements at different joint angles. This method is not exempt from criticalities, such as the cost and the ability to carry out only individual training.
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43
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Methenitis S, Theodorou AA, Chatzinikolaou PN, Margaritelis NV, Nikolaidis MG, Paschalis V. The effects of chronic concentric and eccentric training on position sense and joint reaction angle of the knee extensors. Eur J Sport Sci 2023:1-11. [PMID: 36815692 DOI: 10.1080/17461391.2023.2184726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
The aim of the present study was to compare the effect of chronic concentric or eccentric training on position sense and joint reaction angle, in healthy, untrained young men. Twenty-four men were randomly assigned into a pure concentric (CT) or a pure eccentric (ET) group and performed for 8 weeks, one training session/week, 75 maximal knee extensors contractions. Before and 48 h after the first (W1) and the last (W8) training sessions, knee joint position sense and joint reaction angle were assessed at three different knee angles (i.e. 30°, 45° and 60°). At the same time points, indirect indices of exercise-induced muscle damage (EIMD) were evaluated (i.e. range of motion [ROM], optimal angle, maximum isometric, concentric and eccentric torques, delayed onset muscle soreness [DOMS] and blood creatine kinase concentrations [CK]). Forty-eight hours post W1, position sense, reaction angle and all EIMD indices were significantly changed for both groups (p < 0.05; η2: 0.125-0.618), however, greater alterations were observed after ET. Significant correlations were found, in both groups, between the training-induced changes of position sense, reaction angles and the changes of EIMD biomarkers (r: -0.855-0.825; p < 0.005). No significant changes were found 48 h post W8 for position sense, reaction angle and EIMD indices (p > 0.285) for both CT or ET groups. In conclusion, exercise-induced changes in position sense and reaction angle, were related to the magnitude of EIMD, and not by the type of muscle contraction per se. HighlightsExercise induced changes in position sense and reaction angle, were related to the magnitude of EIMD, and not by the type of muscle contraction per se.After the 1st training session eccentric exercise caused greater disturbances, compared to concentric exercise, in EIMD indices which caused concomitant disturbances to position sense and knee reaction angle.8 weeks of either eccentric or concentric training leads to preservation of position sense and knee reaction angle 48 h after maximal intensity exercise of either types of muscle contraction.
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Affiliation(s)
- S Methenitis
- School of Physical Education and Sport Science, National and Kapodistrian University of Athens, Athens, Greece.,Theseus, Physical Medicine and Rehabilitation Center, Athens, Greece
| | - A A Theodorou
- Department of Life Sciences, School of Sciences, European University, Nicosia, Cyprus
| | - P N Chatzinikolaou
- Department of Physical Education and Sport Science at Serres, Aristotle, University of Thessaloniki, Thessaloniki, Greece
| | - N V Margaritelis
- Department of Physical Education and Sport Science at Serres, Aristotle, University of Thessaloniki, Thessaloniki, Greece
| | - M G Nikolaidis
- Department of Physical Education and Sport Science at Serres, Aristotle, University of Thessaloniki, Thessaloniki, Greece
| | - V Paschalis
- School of Physical Education and Sport Science, National and Kapodistrian University of Athens, Athens, Greece
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44
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Docter H, Podvinšek K, Koomen S. Practical approaches of PULSE Racing in training their athlete for the Cybathlon Global Edition Functional Electrical Stimulation bike race: a case report. J Neuroeng Rehabil 2023; 20:30. [PMID: 36869321 PMCID: PMC9983524 DOI: 10.1186/s12984-023-01143-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 01/20/2023] [Indexed: 03/05/2023] Open
Abstract
During the Cybathlon Global Edition 2020, athletes compete in a Functional Electrical Stimulation (FES) bike race. In this event, athletes with a spinal cord injury cover a distance of 1200 m on an adapted bike by using electrostimulation to activate their leg muscles in order to evoke a pedalling movement. This report reviews the training regimen, as designed by the PULSE Racing team, and the experience of one athlete in preparation for the Cybathlon Global Edition 2020. The training plan was designed to vary exercise modes in order to optimize physiological adaptations and minimize monotony for the athlete. Additional constraints due to coronavirus pandemic, e.g., postponement of the Cybathon Global Edition and modification from a live cycling track to a virtual stationary race, along with the health concerns of the athlete, e.g. unwanted effects from the FES and bladder infection, required creativity to ensure an effective and safe training protocol. The individual needs of the athlete and task requirements for the FES bike race made the design of a suitable training programme challenging, emphasizing the importance of monitoring. Several objective and subjective measures to assess the athlete's health and progress are presented, all with their own advantages and disadvantages. Despite these limitations, the athlete achieved a gold medal in the FES bike race Cybathlon Global Edition 2020 through discipline, team collaboration and the athlete's own motivation.
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Affiliation(s)
- Heleen Docter
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Van Der Boechorststraat 9, 1081 BT, Amsterdam, The Netherlands. .,Amsterdam Movement Sciences, Amsterdam, The Netherlands.
| | - Katja Podvinšek
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Van Der Boechorststraat 9, 1081 BT, Amsterdam, The Netherlands.,Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Sander Koomen
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Van Der Boechorststraat 9, 1081 BT, Amsterdam, The Netherlands.,Amsterdam Movement Sciences, Amsterdam, The Netherlands
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45
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Maroto-Izquierdo S, Nosaka K, Alarcón-Gómez J, Martín-Rivera F. Validity and Reliability of Inertial Measurement System for Linear Movement Velocity in Flywheel Squat Exercise. SENSORS (BASEL, SWITZERLAND) 2023; 23:2193. [PMID: 36850788 PMCID: PMC9958668 DOI: 10.3390/s23042193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 02/08/2023] [Accepted: 02/14/2023] [Indexed: 06/18/2023]
Abstract
The aim of this study was to examine the validity and reliability of an Inertial Measurement System integrated into a secondary pulley (IMS) for determining linear velocity during flywheel squat exercises. Thirty-one male participants who were highly experienced in a flywheel resistance exercise training performed flywheel squat exercises with three incremental loads, and mean velocity (MV), mean propulsive velocity (MPV) and max velocity (Vmax) of the exercises were simultaneously recorded with a validated linear encoder and the IMS, in two different sessions. Validity was analyzed using ordinary least products regression (OLP), Lin's concordance correlation coefficient (CCC), and Hedge's g for the values from the linear encoder and the IMS. Test-retest reliability was determined by coefficient of variation (CV), Intraclass correlation coefficient (ICC), and standard error of measurement (SEM). Results showed a high degree of validity (OLP intercept = -0.09-0.00, OLP slope = 0.95-1.04, CCC = 0.96-0.99, Hedge's g < 0.192, SEM = 0.04-0.08) and reliability (CV < 0.21%, ICC > 0.88, SEM < 0.08). These results confirm that the IMS provides valid and reliable measures of movement velocity during flywheel squat exercises.
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Affiliation(s)
| | - Kazunori Nosaka
- School of Medical and Health Sciences, Centre for Human Performance, Edith Cowan University, Joondalup, WA 6027, Australia
| | - Jesús Alarcón-Gómez
- Research Group in Prevention and Health in Exercise and Sport, University of Valencia, 46010 Valencia, Spain
| | - Fernando Martín-Rivera
- Research Group in Prevention and Health in Exercise and Sport, University of Valencia, 46010 Valencia, Spain
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46
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Nuzzo JL, Pinto MD, Nosaka K. Muscle fatigue during maximal eccentric-only, concentric-only, and eccentric-concentric bicep curl exercise with automated drop setting. Scand J Med Sci Sports 2023; 33:857-871. [PMID: 36752667 DOI: 10.1111/sms.14330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 01/23/2023] [Accepted: 02/03/2023] [Indexed: 02/09/2023]
Abstract
Connected adaptive resistance exercise (CARE) machines are new technology purported to adjust resistance exercise loads in response to muscle fatigue. The present study examined muscle fatigue (strength loss, fatigue perceptions) during maximal eccentric-only (ECCmax -only), concentric-only (CONmax -only), and coupled ECC-CON (ECCmax -CONmax ) bicep curl exercise on a CARE machine. Eleven men and nine women completed the three protocols in separate sessions and in random order. All protocols included 4 sets of 20 maximal effort muscle contractions. Strength loss was calculated as Set 4 set end load minus Set 1 highest load. The CARE machine's algorithm adjusted resistances automatically, permitting continued maximal effort repetitions without stopping. Consequently, all protocols caused substantial fatigue. Women were most susceptible to strength loss from exercise that included maximal efforts in the ECC phase, whereas men were most susceptible to strength loss from exercise that included maximal efforts in the CON phase. With ECCmax -only exercise, ECC strength loss (mean ± SD) was similar between men (55.9 ± 14.1%) and women (56.4 ± 10.8%). However, with CONmax -only exercise, men and women experienced 55.6 ± 6.2% and 35.3 ± 8.7% CON strength loss, respectively. With ECCmax -CONmax exercise, men experienced greater ECC (62.9 ± 7.7%) and CON (77.0 ± 5.3%) strength loss than women (ECC: 48.5 ± 15.7%, CON: 66.2 ± 12.1%). Heightened perceptions of fatigue and pain of the exercised limb were reported after all protocols. Women generally reported more biceps pain than men. The results illustrate CARE technology delivers ECC-only and accentuated ECC exercise feasibly. Acute responses to repeated maximal effort bicep curl exercise with such technology might differ between men and women depending on muscle contraction type.
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Affiliation(s)
- James L Nuzzo
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia
| | - Matheus D Pinto
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia
| | - Kazunori Nosaka
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia
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47
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Yeo SH, Verheul J, Herzog W, Sueda S. Numerical instability of Hill-type muscle models. J R Soc Interface 2023; 20:20220430. [PMID: 36722069 PMCID: PMC9890125 DOI: 10.1098/rsif.2022.0430] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Hill-type muscle models are highly preferred as phenomenological models for musculoskeletal simulation studies despite their introduction almost a century ago. The use of simple Hill-type models in simulations, instead of more recent cross-bridge models, is well justified since computationally 'light-weight'-although less accurate-Hill-type models have great value for large-scale simulations. However, this article aims to invite discussion on numerical instability issues of Hill-type muscle models in simulation studies, which can lead to computational failures and, therefore, cannot be simply dismissed as an inevitable but acceptable consequence of simplification. We will first revisit the basic premises and assumptions on the force-length and force-velocity relationships that Hill-type models are based upon, and their often overlooked but major theoretical limitations. We will then use several simple conceptual simulation studies to discuss how these numerical instability issues can manifest as practical computational problems. Lastly, we will review how such numerical instability issues are dealt with, mostly in an ad hoc fashion, in two main areas of application: musculoskeletal biomechanics and computer animation.
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Affiliation(s)
- Sang-Hoon Yeo
- School of Sport, Exercise & Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - Jasper Verheul
- School of Sport, Exercise & Rehabilitation Sciences, University of Birmingham, Birmingham, UK,Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, UK
| | - Walter Herzog
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Shinjiro Sueda
- Department of Computer Science and Engineering, Texas A&M University, College Station, TX, USA
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48
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Methenitis S, Nomikos T, Mpampoulis T, Kontou E, Kiourelli KM, Evangelidou E, Papadopoulos C, Papadimas G, Terzis G. Different eccentric-based power training volumes improve glycemic, lipidemic profile and body composition of females in a dose-dependent manner: Associations with muscle fibres composition adaptations. Eur J Sport Sci 2023; 23:241-250. [PMID: 35001855 DOI: 10.1080/17461391.2022.2027024] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The present study aimed to investigate the effect of different volumes of fast eccentric-based training on body composition and lipidemic-glycemic profiles in females, as well as to explore the relationship between the change in glycemic-lipidemic profiles and the change in muscle fibre composition. Twenty-nine young females were assigned into three groups and performed 10 weeks (2 training sessions per week) of either 3 (LV), 6 (MV) or 9 (HV) sets/session of four fast velocity eccentric-only half-squats against 70% of concentric 1RM, followed by 3 maximum countermovement jumps (CMJ) after each set. Body composition, vastus lateralis fibre-type composition, and resting blood lipidemic and glycemic indices were evaluated 1 week before and after the training intervention. Significant changes in body composition, fasting glucose, HOMA-IR and blood lipids were found after training with MV and HV (p < 0.05; η2: 0.135-0.390). Significant correlations were found between muscle fibres' percentage cross-sectional areas (%CSA) and resting glycemic-lipid values (r:-0.543to 0.730, p < 0.05). Training-induced changes of glycemic-lipid profiles were highly correlated to those of type IIa and IIx %CSAs (r: -0.895 to 0.898, p < 0.05). Partial Correlations revealed a significant impact of the imposed training volumes on these correlations. These results suggest that six but mostly nine sets per training session of the imposed training stimuli are needed for beneficial changes in resting glycemic-lipidemic profiles, changes which are related to the training-induced changes in muscle fibre composition. However, these relationships are dictated by the imposed training volumes.Highlights Power training induces beneficial changes in body composition, glycemic and lipidemic profiles.Greater training volumes are needed for the healthier changes in glycemic-lipidemic profiles.Higher Type I, IIA and lower IIX percentage cross-sectional areas are linked with healthier body composition and glycemic-lipidemic profiles.Individuals experiencing the greatest increase in Type IIa and decrease in Type IIX muscle fibres cross-sectional areas after power training are those with the greatest beneficial changes in body composition, glycemic and lipidemic profiles.
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Affiliation(s)
- Spyridon Methenitis
- Sports Performance Laboratory, School of Physical Education & Sports Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Tzortzis Nomikos
- Department of Nutrition and Dietetics, School of Health Sciences & Education, Harokopio University, Athens, Greece
| | - Thomas Mpampoulis
- Sports Performance Laboratory, School of Physical Education & Sports Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Eleni Kontou
- Sports Performance Laboratory, School of Physical Education & Sports Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Kleio-Maria Kiourelli
- Department of Nutrition and Dietetics, School of Health Sciences & Education, Harokopio University, Athens, Greece
| | - Eftychia Evangelidou
- Department of Infection Control, G.N.N. Ionias "Konstantopouleio-Patision" Hospital, Athens, Greece
| | - Constantinos Papadopoulos
- A' Neurology Clinic, Aiginition Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - George Papadimas
- A' Neurology Clinic, Aiginition Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Gerasimos Terzis
- Sports Performance Laboratory, School of Physical Education & Sports Science, National and Kapodistrian University of Athens, Athens, Greece
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49
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Le Sant G, Lecharte T, Goreau V, Nordez A, Gross R, Cattagni T. Motor performance, motor impairments, and quality of life after eccentric resistance training in neurological populations: A systematic review and meta-analyses. NeuroRehabilitation 2023; 53:33-50. [PMID: 37424484 DOI: 10.3233/nre-230035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
BACKGROUND Many overlapping factors impair motor performance and quality of life in neurological patients. Eccentric resistance training (ET) has potential benefits for improving motor performance and treating motor impairments better than some traditional rehabilitation approaches. OBJECTIVE To estimate the effect of ET in neurological settings. METHODS Seven databases were reviewed up to May 2022 according to PRSIMA guidelines to find randomized clinical trials involving adults with a neurological condition, who underwent ET as set by the American College of Sports Medicine. Motor performance (main outcome) was assessed as strength, power and capacities during activity. Secondary outcomes (impairments) were muscle structure, flexibility, muscle activity, tone, tremor, balance and fatigue. Tertiary outcomes were risk of fall, and self-reports of quality of life. RESULTS Ten trials were included, assessed using Risk of Bias 2.0 tool, and used to compute meta-analyses. Effective effects in favour of ET were found for strength and power, but not for capacities during activity. Mixed results were found for secondary and tertiary outcomes. CONCLUSION ET may be a promising intervention to better improve strength/power in neurological patients. More studies are needed to improve the quality of evidence underlying changes responsible for these results.
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Affiliation(s)
- Guillaume Le Sant
- Movement - Interactions - Performance (MIP), CHU Nantes, University of Nantes, Nantes, France
- School of Physiotherapy, IFM3, R, Saint-Sébastien-sur-Loire, France
| | - Thomas Lecharte
- Movement - Interactions - Performance (MIP), CHU Nantes, University of Nantes, Nantes, France
| | - Valentin Goreau
- Movement - Interactions - Performance (MIP), CHU Nantes, University of Nantes, Nantes, France
- School of Physiotherapy, IFM3, R, Saint-Sébastien-sur-Loire, France
| | - Antoine Nordez
- Movement - Interactions - Performance (MIP), CHU Nantes, University of Nantes, Nantes, France
- Institut Universitaire de France (IUF), Paris, France
| | - Raphaël Gross
- Movement - Interactions - Performance (MIP), CHU Nantes, University of Nantes, Nantes, France
| | - Thomas Cattagni
- Movement - Interactions - Performance (MIP), CHU Nantes, University of Nantes, Nantes, France
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50
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Dideriksen J, Del Vecchio A. Adaptations in motor unit properties underlying changes in recruitment, rate coding, and maximum force. J Neurophysiol 2023; 129:235-246. [PMID: 36515411 DOI: 10.1152/jn.00222.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Changes in the discharge characteristics of motor units as well as in the maximum force-producing capacity of the muscle are observed following training, aging, and fatiguability. The ability to measure the adaptations in the neuromuscular properties underlying these changes experimentally, however, is limited. In this study we used a computational model to systematically investigate the effects of various neural and muscular adaptations on motor unit recruitment thresholds, average motor unit discharge rates in submaximal contractions, and maximum force. The primary focus was to identify candidate adaptations that can explain experimentally observed changes in motor unit discharge characteristics after 4 wk of strength training (Del Vecchio A, Casolo A, Negro F, Scorcelletti M, Bazzucchi I, Enoka R, Felici F, Farina D. J Physiol 597: 1873-1887, 2019). The simulation results indicated that multiple combinations of adaptations, likely involving an increase in maximum discharge rate across motor units, may occur after such training. On a more general level, we found that the magnitude of the adaptations scales linearly with the change in recruitment thresholds, discharge rates, and maximum force. In addition, the combination of multiple adaptations can be predicted as the linear sum of their individual effects. Together, this implies that the outcomes of the simulations can be generalized to predict the effect of any combination of neural and muscular adaptations. In this way, the study provides a tool for estimating potential underlying adaptations in neural and muscular properties to explain any change in commonly used measures of rate coding, recruitment, and maximum force.NEW & NOTEWORTHY Our ability to measure adaptations in neuromuscular properties in vivo is limited. Using a computational model, we quantify the effect of multiple neuromuscular adaptations on common measures of motor unit recruitment, rate coding, and force-producing capacity. Scaling and combining adaptations had a near-linear effect on these measures, indicating that the results can explain and predict neuromuscular adaptations in a wide range of conditions, including, but not limited to, strength training.
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Affiliation(s)
- Jakob Dideriksen
- Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Alessandro Del Vecchio
- Department Artificial Intelligence in Biomedical Engineering, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
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