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Woods S, McKiel A, Herda T, Klentrou P, Holmes M, Gabriel D, Falk B. Developmental changes in motor unit activity patterns: child-adult comparison using discrete motor unit analysis. Appl Physiol Nutr Metab 2024; 49:904-919. [PMID: 38471135 DOI: 10.1139/apnm-2023-0339] [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: 03/14/2024]
Abstract
Using global surface electromyography (sEMG) and the sEMG threshold it has been suggested that children activate their type-II motor unit (MU) to a lesser extent compared with adults. However, when age-related differences in discrete MU activation are examined using sEMG decomposition this phenomenon is not observed. Furthermore, findings from these studies are inconsistent and conflicting. Therefore, the purpose of this study was to examine differences in discrete MU activation of the vastus lateralis (VL) between boys and men during moderate-intensity knee extensions. Seventeen boys and 20 men completed two laboratory sessions. Following a habituation session, maximal voluntary isometric knee extension (MVIC) torque was determined before completing trapezoidal contractions at 70% MVIC. sEMG of the VL was captured and mathematically decomposed into individual MU action potential trains. Motor unit action potential amplitude (MUAPamp), recruitment threshold (RT), and MU firing rates (MUFR) were calculated. We observed that MUAPamp-RT slope was steeper in men compared with boys (p < 0.05) even after accounting for fat thickness and quadriceps muscle depth. The mean MUFR and y-intercept of the MUFR-RT relationship were significantly (p < 0.001) lower in boys than in men. The slope of the MUFR-RT relationship tended to be steeper in men, but the differences did not reach statistical significance (p = 0.056). Overall, our results suggest that neural strategies used to produce torque are different among boys and men. Such differences may be related, in part, to boys' lower MUFR and lesser ability to activate their higher-threshold MUs. Although, other factors (e.g., muscle composition) likely also play a role.
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Affiliation(s)
- Stacey Woods
- Department of Kinesiology, Brock University, St. Catharines, ON, Canada
| | - Andrew McKiel
- Department of Kinesiology, Brock University, St. Catharines, ON, Canada
- Centre for Bone and Muscle Health, Brock University, St. Catharines, ON, Canada
| | - Trent Herda
- School of Education and Human Sciences, University of Kansas, Lawrence, KS, USA
| | - Panagiota Klentrou
- Department of Kinesiology, Brock University, St. Catharines, ON, Canada
- Centre for Bone and Muscle Health, Brock University, St. Catharines, ON, Canada
| | - Michael Holmes
- Department of Kinesiology, Brock University, St. Catharines, ON, Canada
- Centre for Bone and Muscle Health, Brock University, St. Catharines, ON, Canada
| | - David Gabriel
- Department of Kinesiology, Brock University, St. Catharines, ON, Canada
| | - Bareket Falk
- Department of Kinesiology, Brock University, St. Catharines, ON, Canada
- Centre for Bone and Muscle Health, Brock University, St. Catharines, ON, Canada
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Olmos AA, Sontag SA, Sterczala AJ, Parra ME, Dimmick HL, Miller JD, Deckert JA, Herda TJ, Trevino MA. High-Intensity Cycling Training Necessitates Increased Neuromuscular Demand of the Vastus Lateralis During a Fatiguing Contraction. RESEARCH QUARTERLY FOR EXERCISE AND SPORT 2024; 95:313-324. [PMID: 37369135 DOI: 10.1080/02701367.2023.2201311] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 04/05/2023] [Indexed: 06/29/2023]
Abstract
Purpose: To examine the effects of a 5-week continuous cycling training intervention on electromyographic amplitude (EMGRMS)- and mechanomyographic amplitude (MMGRMS)-torque relationships of the vastus lateralis (VL) during a prolonged contraction. Methods: Twenty-four sedentary, young adults performed maximal voluntary contractions (MVCs) and a prolonged isometric trapezoidal contraction at the same absolute 40% MVC for the knee extensors before (PRE) and after training (POSTABS). Individual b- (slopes) and a-terms (y-intercepts) were calculated from the log-transformed electromyographic amplitude (EMGRMS)- and mechanomyographic amplitude (MMGRMS)-torque relationships during the increasing and decreasing segments of the trapezoid. EMGRMS and MMGRMS was normalized for the 45-s steady torque segment. Results: At PRE, b-terms for the EMGRMS-torque relationships during the linearly decreasing segment were greater than the increasing segment (p < .001), and decreased from PRE to POSTABS (p = .027). a-terms were greater during the linearly increasing than decreasing segment at PRE, while the a-terms for the linearly decreasing segment increased from PRE to POSTABS (p = .027). For the MMGRMS-torque relationships, b-terms during the linearly decreasing segment decreased from PRE to POSTABS (p = .013), while a-terms increased from PRE to POSTABS when collapsed across segments (p = .022). Steady torque EMGRMS increased for POSTABS (p < .001). Conclusion: Although cycling training increased aerobic endurance, incorporating resistance training may benefit athletes/individuals as the alterations in neuromuscular parameters post-training suggest a greater neural cost (EMGRMS) and mechanical output (MMGRMS) to complete the same pre-training fatiguing contraction.
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Homma H, Teshigawara N, Deguchi M, Saito M, Mochizuki Y, DE Almeida KY, Kozuma A, Tashiro S, Kikuchi S, Yumoto K, Matsumoto S, Nishiyama T, Kikuchi N. Effect of sprint interval training load on maximal oxygen uptake in trained men. J Sports Med Phys Fitness 2024; 64:328-333. [PMID: 37800403 DOI: 10.23736/s0022-4707.23.15370-9] [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: 10/07/2023]
Abstract
BACKGROUND Sprint interval training (SIT) improves maximal aerobic and anaerobic performance, including oxygen uptake (VO2max), power output, and sprint performance. This study aimed to investigate the effect of SIT load on V̇O2max in trained subjects. METHODS SIT was performed twice a week for three weeks by twenty-four trained men (aged: 20.7±2.7, V̇O2max 43.6±6.5) and consisted of seven bouts of 10-s cycling sprints followed by a 4-min rest. Subjects were divided into two groups depending on the relative resistance of the load compared to their body mass (BM): 7.5% (S7.5) and 10% (S10). We measured the peak power, mean power, and peak cadence in SIT during the first and final sessions. V̇O2max, maximum aerobic power (MAP), heart rate, and lactate (La) concentration were measured before and after SIT using incremental tests. RESULTS After 3 weeks of SIT, V̇O2max, MAP, and La improved significantly in both S7.5 and S10 groups. In addition, changes in V̇O2max in S10 were higher than those in S7.5 (2.2±11.2% vs. 9.23±9.57%, P=0.029, adjusted by pre V̇O2max). MAP measurements showed the same results (2.2±11.3% vs. 8.3±10.0%, P=0.015, adjusted by pre-MAP). However, there was no significant interaction between time and group. A significant increase in peak cadence from first session to sixth sessions was observed in S7.5 (P=0.01, ES = 0.93, 95% confidence interval [CI]: 0.02-1.78) but not in S10 (P=0.132, ES = 0.22, 95% [CI]: -0.59-1.01). CONCLUSIONS Our results suggest that 3 weeks of SIT improves endurance performance in trained subjects. It seems that SIT at 10% load may tend to be more effective.
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Affiliation(s)
- Hiroki Homma
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Nobuaki Teshigawara
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Minoru Deguchi
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Mika Saito
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Yukina Mochizuki
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Kathleen Y DE Almeida
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Ayumu Kozuma
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Sora Tashiro
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Sayaka Kikuchi
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Kenichi Yumoto
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Shingo Matsumoto
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Tetsunari Nishiyama
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Naoki Kikuchi
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan -
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Zhong R, Rua MT, Wei-LaPierre L. Targeting mitochondrial Ca 2+ uptake for the treatment of amyotrophic lateral sclerosis. J Physiol 2024; 602:1519-1549. [PMID: 38010626 PMCID: PMC11032238 DOI: 10.1113/jp284143] [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: 09/06/2023] [Accepted: 10/31/2023] [Indexed: 11/29/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a rare adult-onset neurodegenerative disease characterized by progressive motor neuron (MN) loss, muscle denervation and paralysis. Over the past several decades, researchers have made tremendous efforts to understand the pathogenic mechanisms underpinning ALS, with much yet to be resolved. ALS is described as a non-cell autonomous condition with pathology detected in both MNs and non-neuronal cells, such as glial cells and skeletal muscle. Studies in ALS patient and animal models reveal ubiquitous abnormalities in mitochondrial structure and function, and disturbance of intracellular calcium homeostasis in various tissue types, suggesting a pivotal role of aberrant mitochondrial calcium uptake and dysfunctional calcium signalling cascades in ALS pathogenesis. Calcium signalling and mitochondrial dysfunction are intricately related to the manifestation of cell death contributing to MN loss and skeletal muscle dysfunction. In this review, we discuss the potential contribution of intracellular calcium signalling, particularly mitochondrial calcium uptake, in ALS pathogenesis. Functional consequences of excessive mitochondrial calcium uptake and possible therapeutic strategies targeting mitochondrial calcium uptake or the mitochondrial calcium uniporter, the main channel mediating mitochondrial calcium influx, are also discussed.
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Affiliation(s)
- Renjia Zhong
- Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Gainesville, FL, 32611
- Department of Emergency Medicine, the First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China, 110001
| | - Michael T. Rua
- Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Gainesville, FL, 32611
| | - Lan Wei-LaPierre
- Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Gainesville, FL, 32611
- Myology Institute, University of Florida, Gainesville, FL 32611
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Wu C, Deng J, Gao C. Effects of pre-sleep protein supplementation on plasma markers of muscle damage and inflammatory cytokines resulting from sprint interval training in trained swimmers. J Int Soc Sports Nutr 2023; 20:2244478. [PMID: 37543952 PMCID: PMC10405750 DOI: 10.1080/15502783.2023.2244478] [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: 04/17/2023] [Accepted: 07/28/2023] [Indexed: 08/08/2023] Open
Abstract
BACKGROUND Pre-sleep protein has been shown to improve muscle recovery overnight following exercise-induced muscle damage. Whether such an approach affects recovery from sprint interval training (SIT) has yet to be elucidated. This study examined the effects of protein supplementation every night before sleep on early (45 min post-SIT) and late (24 and 48 h after SIT) responses of creatine kinase (CK) and inflammatory cytokines, including interleukin-6 and 10 (IL-6 and IL-10) and tumor necrosis factor-alpha (TNFα). METHODS Twenty trained swimmers underwent a 2-week in-water swimming SIT (two sets of 12 × 50-m all-out swims, interspersed by 1:1 recovery between each sprint and 3 min of rest between sets) and were randomized to two intervention groups receiving either 0.5 g kg-1 day-1 protein beverage (PRO) or the same amount of carbohydrate (CHO) preceding going to bed every night. For initial and final training sessions, CK and cytokine responses were analyzed at different time points, including resting, immediately after completion, 45 min post-SIT, and 24 and 48 h after SIT. RESULTS CK concentrations elevated from resting point to 24 and 48 h post-SIT for both PRO and CHO groups (p < 0.05). In both training groups, the peak levels of IL-6 and 10 were observed 45 min post-SIT on both occasions. TNFα levels significantly elevated from rest to immediately after SIT (p < 0.001) and returned to values equivalent to the baseline afterward in both groups and on both occasions. In both groups, swimming SIT also switched the cytokine response 48 hours after exercise to an anti-inflammatory status by decreasing the ratio of IL-6 to IL-10 (p < 0.04) in the last training session. CONCLUSIONS Pre-sleep protein ingestion failed to ameliorate blood markers of muscle damage. The late anti-inflammatory profile of cytokines and exercise-induced muscle damage improved after two weeks of swimming SIT with either protein or carbohydrate ingestion before sleep.
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Affiliation(s)
- Cairong Wu
- Zhengde Polytechnic College, Department of Public Education, Nanjing, Jiangsu, China
- Adamson University, Graduate School, Metro Manila, Philippines
| | - Jie Deng
- Nanjing University of Aeronautics and Astronautics, Department of Physical Education, Nanjing, Jiangsu, China
| | - Chengli Gao
- Sanjiang University, Department of Physical Education, Nanjing, Jiangsu, China
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Holmes AJ, Stratton MT, Bailly AR, Gottschall JS, Feito Y, Ha PL, Lavigne A, Persaud K, Gagnon HL, Krueger A, Modjeski A, Esmat TA, Harper LN, VanDusseldorp TA, Hester GM. Effects of plyometric- and cycle-based high-intensity interval training on body composition, aerobic capacity, and muscle function in young females: a field-based group fitness assessment. Appl Physiol Nutr Metab 2023; 48:932-945. [PMID: 37556856 DOI: 10.1139/apnm-2022-0465] [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: 08/11/2023]
Abstract
High-intensity interval training (HIIT) is an effective alternative to moderate intensity continuous training for improvements in body composition and aerobic capacity; however, there is little work comparing different modalities of HIIT. The purpose of this study was to compare the effects of plyometric- (PLYO) and cycle-oriented (CYC) HIIT on body composition, aerobic capacity, and skeletal muscle size, quality, and function in recreationally trained females. Young (21.7 ± 3.1 yrs), recreationally active females were quasi-randomized (1:1 ratio) to 8 weeks of twice weekly PLYO (n = 15) or CYC (n = 15) HIIT. Body composition (four-compartment model), VO2peak, countermovement jump performance, muscle size, and echo intensity (muscle quality), as well as strength and power of the knee extensors and plantar flexors were measured before and after training. Both groups showed a similar decrease in body fat percentage (p < 0.001;η p 2 = 0.409) and echo intensity (p < 0.001;η p 2 = 0.558), and an increase in fat-free mass (p < 0.001;η p 2 = 0.367) and VO2peak (p = 0.001;η p 2 = 0.318). Muscle size was unaffected (p > 0.05), whereas peak torque was reduced similarly in both groups (p = 0.017;η p 2 = 0.188) and rapid torque capacity was diminished only for the knee extensors after CYC (p = 0.022; d = -0.67). These results suggest that PLYO and CYC HIIT are similarly effective for improving body composition, aerobic capacity, and muscle quality, whereas muscle function may express moderate decrements in recreationally active females. ClinicalTrials.gov (NCT05821504).
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Affiliation(s)
- A J Holmes
- Department of Exercise Science and Sport Management, Kennesaw State University, GA, USA
| | - M T Stratton
- Department of Health, Kinesiology, and Sport, University of South Alabama, AL, USA
| | - A R Bailly
- Department of Exercise Science and Sport Management, Kennesaw State University, GA, USA
| | - J S Gottschall
- Department of Integrative Physiology, University of Colorado, CO, USA
| | - Y Feito
- Nea Onnim Consultancy, St. Augustine, FL, USA
| | - P L Ha
- Department of Exercise Science and Sport Management, Kennesaw State University, GA, USA
| | - A Lavigne
- Dr. Betty L. Siegel Student Recreation and Activities Center, Kennesaw State University, GA, USA
| | - K Persaud
- Department of Exercise Science and Sport Management, Kennesaw State University, GA, USA
| | - H L Gagnon
- Department of Exercise Science and Sport Management, Kennesaw State University, GA, USA
| | - A Krueger
- Department of Exercise Science and Sport Management, Kennesaw State University, GA, USA
| | - A Modjeski
- Department of Exercise Science and Sport Management, Kennesaw State University, GA, USA
| | - T A Esmat
- Department of Exercise Science and Sport Management, Kennesaw State University, GA, USA
| | - L N Harper
- Department of Exercise Science and Sport Management, Kennesaw State University, GA, USA
| | - T A VanDusseldorp
- Bonafide Health, LLC, JDS Therapeutics, NY, USA
- Department of Health and Exercise Sciences, Jacksonville University, FL, USA
| | - G M Hester
- Department of Exercise Science and Sport Management, Kennesaw State University, GA, USA
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Caparrós-Manosalva C, Garrido-Muñoz N, Alvear-Constanzo B, Sanzana-Laurié S, Artigas-Arias M, Alegría-Molina A, Vidal-Seguel N, Espinoza-Araneda J, Huard N, Pagnussat AS, Sapunar J, Salazar LA, Marzuca-Nassr GN. Effects of high-intensity interval training on lean mass, strength, and power of the lower limbs in healthy old and young people. Front Physiol 2023; 14:1223069. [PMID: 37829114 PMCID: PMC10565117 DOI: 10.3389/fphys.2023.1223069] [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: 05/15/2023] [Accepted: 08/25/2023] [Indexed: 10/14/2023] Open
Abstract
Introduction: Whether high-intensity interval training (HIIT) can improve lean mass, strength, and power of the lower limbs in young and older people is still under discussion. This study aimed to determine the effect of HIIT on lean mass, maximal strength, rate of force development (RFD), and muscle power of both lower limbs in healthy young and older adults. Secondarily, to compare the effects of HIIT between dominant vs. non-dominant lower limbs of each group. Materials and methods: Healthy older (n = 9; 66 ± 6 years; BMI 27.1 ± 3.1 kg m-2) and young (n = 9; 21 ± 1 years; BMI 26.2 ± 2.8 kg m-2) men underwent 12 weeks of HIIT (3x/week) on a stationary bicycle. The evaluations were made before and after the HIIT program by dual energy X-ray absorptiometry (DEXA), anthropometry, force transducer and, Sit-to-Stand test. The outcomes analyzed were limb lean mass, thigh circumference, maximal voluntary isometric strength, RFD (Time intervals: 0-50, 50-100, 100-200, and 0-200 ms), and muscle power in both lower limbs. Results: After 12 weeks of HIIT, non-dominant limb (NDL) showed increase in limb lean mass (p < 0.05) but without interaction (time*group). HIIT showed a gain in absolute maximal strength and also when adjusted for thigh circumference in the dominant lower limb (DL) in both groups. The RFD0-200 ms showed differences between groups but without interaction. The RFD0-50 ms of the NDL showed post-training improvements (p < 0.05) in both groups. Only the older group showed differences between DL vs. NDL in most of the RFD obtained post-intervention. In addition, post-HIIT muscle power gain was observed in both groups (p < 0.05), but mainly in older adults. Conclusion: HIIT promotes increases in lean mass, maximal strength, early RFD, and lower limb muscle power in healthy older and young individuals. The differences shown between the DL and the NDL must be analyzed in future studies.
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Affiliation(s)
- Cristian Caparrós-Manosalva
- Department of Human Movement Sciences, Faculty of Health Sciences, University of Talca, Talca, Chile
- Rehabilitation Sciences Graduate Program, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, Brazil
- Interuniversity Center for Healthy Aging, Talca, Chile
| | - Nicolás Garrido-Muñoz
- Interuniversity Center for Healthy Aging, Talca, Chile
- Universidad de La Frontera, Facultad de Medicina, Departamento de Ciencias de la Rehabilitación, Temuco, Chile
| | - Bastián Alvear-Constanzo
- Interuniversity Center for Healthy Aging, Talca, Chile
- Universidad de La Frontera, Facultad de Medicina, Departamento de Ciencias de la Rehabilitación, Temuco, Chile
| | - Sofía Sanzana-Laurié
- Interuniversity Center for Healthy Aging, Talca, Chile
- Universidad de La Frontera, Facultad de Medicina, Departamento de Ciencias de la Rehabilitación, Temuco, Chile
| | - Macarena Artigas-Arias
- Interuniversity Center for Healthy Aging, Talca, Chile
- Universidad de La Frontera, Facultad de Medicina, Departamento de Ciencias de la Rehabilitación, Temuco, Chile
- Universidad de La Frontera, Facultad de Ciencias Agropecuarias y Medioambiente, Doctorado en Ciencias Mención Biología Celular y Molecular Aplicada, Temuco, Chile
| | - Andrea Alegría-Molina
- Interuniversity Center for Healthy Aging, Talca, Chile
- Universidad de La Frontera, Facultad de Medicina, Departamento de Ciencias de la Rehabilitación, Temuco, Chile
| | - Nicolás Vidal-Seguel
- Interuniversity Center for Healthy Aging, Talca, Chile
- Universidad de La Frontera, Facultad de Medicina, Departamento de Ciencias de Ciencias Básicas, Temuco, Chile
- Universidad de La Frontera, Facultad de Medicina, Doctorado en Ciencias Morfológicas, Temuco, Chile
| | - Jessica Espinoza-Araneda
- Department of Human Movement Sciences, Faculty of Health Sciences, University of Talca, Talca, Chile
- Rehabilitation Sciences Graduate Program, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, Brazil
- Interuniversity Center for Healthy Aging, Talca, Chile
| | - Nolberto Huard
- Universidad de La Frontera, Facultad de Medicina, Departamento de Ciencias Básicas, Centro de Biología Molecular y Farmacogenética, Temuco, Chile
| | - Aline Souza Pagnussat
- Rehabilitation Sciences Graduate Program, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, Brazil
- Department of Physical Therapy, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Brazil
- Department of Physical Therapy, Georgia State University, Atlanta, GA, United States
| | - Jorge Sapunar
- Universidad de La Frontera, Facultad de Medicina, Departamento de Medicina Interna, Temuco, Chile
| | - Luis A. Salazar
- Universidad de La Frontera, Facultad de Medicina, Departamento de Ciencias Básicas, Centro de Biología Molecular y Farmacogenética, Temuco, Chile
| | - Gabriel Nasri Marzuca-Nassr
- Interuniversity Center for Healthy Aging, Talca, Chile
- Universidad de La Frontera, Facultad de Medicina, Departamento de Ciencias de la Rehabilitación, Temuco, Chile
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Liu Y, Zhou A, Li F, Yue T, Xia Y, Yao Y, Zhou X, Zhang Y, Wang Y. Aerobic capacity and [Formula: see text] kinetics adaptive responses to short-term high-intensity interval training and detraining in untrained females. Eur J Appl Physiol 2023; 123:1685-1699. [PMID: 36995431 DOI: 10.1007/s00421-023-05182-8] [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: 10/27/2022] [Accepted: 03/14/2023] [Indexed: 03/31/2023]
Abstract
PURPOSE This study investigated the physical fitness and oxygen uptake kinetics (τ[Formula: see text]) along with the O2 delivery and utilization (heart rate kinetics, τHR; deoxyhemoglobin/[Formula: see text] ratio, ∆[HHb]/[Formula: see text]) adaptations of untrained female participants responding to 4 weeks of high-intensity interval training (HIIT) and 2 weeks of detraining. METHODS Participants were randomly assigned to HIIT (n = 11, 4 × 4 protocol) or nonexercising control (n = 9) groups. Exercising group engaged 4 weeks of treadmill HIIT followed by 2 weeks of detraining while maintaining daily activity level. Ramp-incremental (RI) tests and step-transitions to moderate-intensity exercise were performed. Aerobic capacity and performance (maximal oxygen uptake, [Formula: see text]; gas-exchange threshold, GET; power output, PO), body composition (skeletal muscle mass, SMM; body fat percentage, BF%), muscle oxygenation status (∆[HHb]), [Formula: see text], and HR kinetics were assessed. RESULTS HIIT elicited improvements in aerobic capacity ([Formula: see text], + 0.17 ± 0.04 L/min; GET, + 0.18 ± 0.05 L/min, P < 0.01; PO-[Formula: see text], ± 23.36 ± 8.37 W; PO-GET, + 17.18 ± 3.07 W, P < 0.05), body composition (SMM, + 0.92 ± 0.17 kg; BF%, - 3.08% ± 0.58%, P < 0.001), and speed up the τ[Formula: see text] (- 8.04 ± 1.57 s, P < 0.001) significantly, extending to better ∆[HHb]/[Formula: see text] ratio (1.18 ± 0.08 to 1.05 ± 0.14). After a period of detraining, the adaptation in body composition and aerobic capacity, as well as the accelerated τ[Formula: see text] were maintained in the HIIT group, but the PO-[Formula: see text] and PO-GET declined below the post-training level (P < 0.05), whereas no changes were reported in controls (P > 0.05). Four weeks of HIIT induced widespread physiological adaptations in females, and the majority of improvements were preserved after 2 weeks of detraining except for power output corresponding to [Formula: see text] and GET.
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Affiliation(s)
- Yujie Liu
- School of Sports Medicine and Rehabilitation, Beijing Sport University, Beijing, 100084, China
| | - Aiyi Zhou
- School of Sports Medicine and Rehabilitation, Beijing Sport University, Beijing, 100084, China
| | - Fengya Li
- School of Sports Medicine and Rehabilitation, Beijing Sport University, Beijing, 100084, China
| | - Tian Yue
- School of Sports Medicine and Rehabilitation, Beijing Sport University, Beijing, 100084, China
| | - Yuncan Xia
- School of Sports Medicine and Rehabilitation, Beijing Sport University, Beijing, 100084, China
| | - Yibing Yao
- School of Sports Medicine and Rehabilitation, Beijing Sport University, Beijing, 100084, China
| | - Xiaoxiao Zhou
- School of Sports Medicine and Rehabilitation, Beijing Sport University, Beijing, 100084, China
| | - Yihong Zhang
- School of Sports Medicine and Rehabilitation, Beijing Sport University, Beijing, 100084, China
| | - Yan Wang
- School of Sports Medicine and Rehabilitation, Beijing Sport University, Beijing, 100084, China.
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9
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Scoubeau C, Carpentier J, Baudry S, Faoro V, Klass M. Body composition, cardiorespiratory fitness, and neuromuscular adaptations induced by a home-based whole-body high intensity interval training. J Exerc Sci Fit 2023; 21:226-236. [PMID: 36970125 PMCID: PMC10034507 DOI: 10.1016/j.jesf.2023.02.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 02/17/2023] [Accepted: 02/24/2023] [Indexed: 03/12/2023] Open
Abstract
Background/objective Bodyweight exercises performed at home could be a complementary approach to improve health-related fitness in people having little spare time and during stay-at-home periods. This study then investigated body composition, cardiorespiratory fitness, and neuromuscular adaptations to a home-based, video-directed, whole-body high-intensity interval training (WB-HIIT). Methods Fourteen subjects participated to an 8-week WB-HIIT (6 females, 23 ± 1 years) and fourteen were included in a non-exercise control group (CTL; 6 females, 24 ± 4 years). All took part to pre- and post-intervention assessments of body composition, peak oxygen uptake (VO2peak) and first ventilatory threshold (VT1; index of aerobic capacity), dynamic (leg press 3-repetition maximum) and isometric strength (knee extensors maximal isometric contractions with assessment of voluntary activation), and muscle endurance during an isometric submaximal contraction maintained till exhaustion. WB-HIIT consisted in 30-s all-out whole-body exercises interspaced with 30 s of active recovery. Training sessions were performed at home by means of videos with demonstration of exercises. Heart rate was monitored during sessions. Results WB-HIIT increased VO2peak (5%), VT1 (20%), leg lean mass (3%), dynamic (13%) and isometric strength (6%), and muscle endurance (28%; p < 0.05), while they did not improve in CTL. VO2peak increase was correlated (r = 0.56; p < 0.05) with the time spent above 80% of maximal heart rate during training sessions. Isometric strength increase was correlated with change in voluntary activation (r = 0.74; p < 0.01). Conclusion The home-based WB-HIIT induced concomitant cardiorespiratory fitness and neuromuscular improvements. The predominant effect was observed for aerobic capacity and muscle endurance which could improve exercise tolerance and reduce fatigability.
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Affiliation(s)
- Corentin Scoubeau
- Cardio-Pulmonary Exercise Laboratory, Faculty of Motor Sciences, Université libre de Bruxelles, Belgium
| | - Julie Carpentier
- Research Unit in Biometry and Exercise Nutrition, Faculty of Motor Sciences, Université libre de Bruxelles, Belgium
| | - Stéphane Baudry
- Laboratory of Applied Biology and Research Unit in Applied Neurophysiology, Faculty of Motor Sciences, ULB Neuroscience Institute, Université libre de Bruxelles, Belgium
| | - Vitalie Faoro
- Cardio-Pulmonary Exercise Laboratory, Faculty of Motor Sciences, Université libre de Bruxelles, Belgium
| | - Malgorzata Klass
- Research Unit in Biometry and Exercise Nutrition, Faculty of Motor Sciences, Université libre de Bruxelles, Belgium
- Laboratory of Applied Biology and Research Unit in Applied Neurophysiology, Faculty of Motor Sciences, ULB Neuroscience Institute, Université libre de Bruxelles, Belgium
- Corresponding author. Research Unit in Biometry and Exercise Nutrition, Faculty of Motor Sciences, Université libre de Bruxelles, Belgium.
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10
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Telles GD, Libardi CA, Conceição MS, Vechin FC, Lixandrão ME, Mangone FRR, Pavanelli AC, Nagai MA, Camera DM, Hawley JA, Ugrinowitsch C. Interrelated but Not Time-Aligned Response in Myogenic Regulatory Factors Demethylation and mRNA Expression after Divergent Exercise Bouts. Med Sci Sports Exerc 2023; 55:199-208. [PMID: 36136603 DOI: 10.1249/mss.0000000000003049] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
INTRODUCTION DNA methylation regulates exercise-induced changes in the skeletal muscle transcriptome. However, the specificity and the time course responses in the myogenic regulatory factors DNA methylation and mRNA expression after divergent exercise modes are unknown. PURPOSE This study aimed to compare the time course changes in DNA methylation and mRNA expression for selected myogenic regulatory factors ( MYOD1 , MYF5 , and MYF6 ) immediately after, 4 h after, and 8 h after a single bout of resistance exercise (RE), high-intensity interval exercise (HIIE), and concurrent exercise (CE). METHODS Nine healthy but untrained males (age, 23.9 ± 2.8 yr; body mass, 70.1 ± 14.9 kg; peak oxygen uptake [V̇O 2peak ], 41.4 ± 5.2 mL·kg -1 ·min -1 ; mean ± SD) performed a counterbalanced, randomized order of RE (4 × 8-12 repetition maximum), HIIE (12 × 1 min sprints at V̇O 2peak running velocity), and CE (RE followed by HIIE). Skeletal muscle biopsies (vastus lateralis) were taken before (REST) immediately (0 h), 4 h, and 8 h after each exercise bout. RESULTS Compared with REST, MYOD1 , MYF5 , and MYF6 , mean methylation across all CpGs analyzed was reduced after 4 and 8 h in response to all exercise protocols ( P < 0.05). Reduced levels of MYOD1 methylation were observed after HIIE and CE compared with RE ( P < 0.05). Compared with REST, all exercise bouts increased mRNA expression over time ( MYOD1 at 4 and 8 h, and MYF6 at 4 h; P < 0.05). MYF5 mRNA expression was lower after 4 h compared with 0 h and higher at 8 h compared with 4 h ( P < 0.05). CONCLUSIONS We observed an interrelated but not time-aligned response between the exercise-induced changes in myogenic regulatory factors demethylation and mRNA expression after divergent exercise modes. Despite divergent contractile stimuli, changes in DNA methylation and mRNA expression in skeletal muscle were largely confined to the late (4-8 h) recovery period and similar between the different exercise challenges.
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Affiliation(s)
- Guilherme Defante Telles
- Laboratory of Neuromuscular Adaptations to Strength Training, School of Physical Education and Sport, University of São Paulo, São Paulo, São Paulo, BRAZIL
| | - Cleiton Augusto Libardi
- MUSCULAB-Laboratory of Neuromuscular Adaptations to Resistance Training, Department of Physical Education, Federal University of São Carlos, São Carlos, São Paulo, BRAZIL
| | - Miguel Soares Conceição
- MUSCULAB-Laboratory of Neuromuscular Adaptations to Resistance Training, Department of Physical Education, Federal University of São Carlos, São Carlos, São Paulo, BRAZIL
| | - Felipe Cassaro Vechin
- Laboratory of Neuromuscular Adaptations to Strength Training, School of Physical Education and Sport, University of São Paulo, São Paulo, São Paulo, BRAZIL
| | | | | | | | | | - Donny Michael Camera
- Department of Health and Medical Sciences, Swinburne University, Melbourne, VIC, AUSTRALIA
| | - John A Hawley
- Mary MacKillop Institute for Health Research, Exercise and Nutrition Research Program, Australian Catholic University, Melbourne, VIC, AUSTRALIA
| | - Carlos Ugrinowitsch
- Laboratory of Neuromuscular Adaptations to Strength Training, School of Physical Education and Sport, University of São Paulo, São Paulo, São Paulo, BRAZIL
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11
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Aeles J, Kelly LA, Cresswell AG. Flexor hallucis brevis motor unit behavior in response to moderate increases in rate of force development. PeerJ 2023; 11:e14341. [PMID: 36643633 PMCID: PMC9838207 DOI: 10.7717/peerj.14341] [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: 06/11/2021] [Accepted: 10/13/2022] [Indexed: 01/11/2023] Open
Abstract
Background Studies on motor unit behaviour with varying rates of force development have focussed predominantly on comparisons between slow and ballistic (i.e., very fast) contractions. It remains unclear how motor units respond to less extreme changes in rates of force development. Here, we studied a small intrinsic foot muscle, flexor hallucis brevis (FHB) where the aim was to compare motor unit discharge rates and recruitment thresholds at two rates of force development. We specifically chose to investigate relatively slow to moderate rates of force development, not ballistic, as the chosen rates are more akin to those that presumably occur during daily activity. Methods We decomposed electromyographic signals to identify motor unit action potentials obtained from indwelling fine-wire electrodes in FHB, from ten male participants. Participants performed isometric ramp-and-hold contractions from relaxed to 50% of a maximal voluntary contraction. This was done for two rates of force development; one with the ramp performed over 5 s (slow condition) and one over 2.5 s (fast condition). Recruitment thresholds and discharge rates were calculated over the ascending limb of the ramp and compared between the two ramp conditions for matched motor units. A repeated measures nested linear mixed model was used to compare these parameters statistically. A linear repeated measures correlation was used to assess any relationship between changes in recruitment threshold and mean discharge rate between the two conditions. Results A significant increase in the initial discharge rate (i.e., at recruitment) in the fast (mean: 8.6 ± 2.4 Hz) compared to the slow (mean: 7.8 ± 2.3 Hz) condition (P = 0.027), with no changes in recruitment threshold (P = 0.588), mean discharge rate (P = 0.549) or final discharge rate (P = 0.763) was observed. However, we found substantial variability in motor unit responses within and between conditions. A small but significant negative correlation (R2 = 0.33, P = 0.003) was found between the difference in recruitment threshold and the difference in mean discharge rate between the two conditions. Conclusion These findings suggest that as force increases for contractions with slower force development, increasing the initial discharge rate of recruited motor units produces the increase in rate of force development, without a change in their recruitment thresholds, mean or final discharge rate. However, an important finding was that for only moderate changes in rate of force development, as studied here, not all units respond similarly. This is different from what has been described in the literature for ballistic contractions in other muscle groups, where all motor units respond similarly to the increase in neural drive. Changing the discharge behaviour of a small group of motor units may be sufficient in developing force at the required rate rather than having the discharge behaviour of the entire motor unit pool change equally.
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Affiliation(s)
- Jeroen Aeles
- School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Queensland, Australia,Laboratory of Functional Morphology, Department of Biology, University of Antwerp, Antwerp, Belgium,Laboratory “Movement, Interactions, Performance” (EA 4334), Université de Nantes, Nantes, France
| | - Luke A. Kelly
- School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Andrew G. Cresswell
- School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Queensland, Australia
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12
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Vardakis L, Michailidis Y, Mandroukas A, Zelenitsas C, Mavrommatis G, Metaxas T. Effects of a shock microcycle after COVID-19 lockdown period in elite soccer players. Sci Sports 2022; 37:572-580. [PMID: 36062208 PMCID: PMC9420708 DOI: 10.1016/j.scispo.2022.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 07/13/2022] [Indexed: 11/29/2022]
Abstract
Objectives Decreases in physical fitness are inevitable after two to six week period of detraining in athletes. Lockdown period changed the characteristics of soccer players’ training. Aim of the study The aim of our study was to apply a HIIT shock-microcycle (SM) after return to training and assess its effect on players’ performance. Equipment and methods Nineteen elite professional soccer players during the lockdown period (LP) from March to May 2020 (8 weeks) performed 3-4 individual training sessions per week. The training sessions included running boots of anaerobic short and aerobic prolonged duration intervals. Intensity was determined according to lab ergospirometry test 2 weeks before LP. All the players followed an indoor program, 3–6 sessions per week consisted of core, balance and flexibility exercises (∼45 minutes). SM training content was same for both groups and took place the first two weeks after LP, consisted by eight high intensity interval training sessions (HIIT), two technique, two tactical sessions and two days off. Results Repeated sprint ability mean time (RSAMeanTime) and Repeated sprint ability performance–sprint no 4,5,6 (RSA4,5,6S) improved after SM (P = 0.025, Effect size: r2 = 0.331, P = 0.010, Effect size: r2 = 0.411, p = 0.009, Effect size: r2 = 0.418, P = 0.037, Effect size: r2 = 0.293, respectively. Yo-Yo intermitted recovery test level 2 (YYIR2TotalDistance) that covered by players during the 2nd measurement was 10.8% longer (P = 0.004, Effect size: r2 = 0.483). Also, the YYIR2HeartRateRecovery percentage was lower during the 2nd measurement (P = 0.014, Effect size: r2 = 0.107). Conclusions These results indicate that SM can improve YYIR2 and RSA performance thus it is a useful tool to regain physical attributes in a short period.
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13
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Lulic-Kuryllo T, Greig Inglis J. Sex differences in motor unit behaviour: A review. J Electromyogr Kinesiol 2022; 66:102689. [DOI: 10.1016/j.jelekin.2022.102689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 07/28/2022] [Accepted: 07/29/2022] [Indexed: 10/15/2022] Open
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14
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Guo Y, Piasecki J, Swiecicka A, Ireland A, Phillips BE, Atherton PJ, Stashuk D, Rutter MK, McPhee JS, Piasecki M. Circulating testosterone and dehydroepiandrosterone are associated with individual motor unit features in untrained and highly active older men. GeroScience 2022; 44:1215-1228. [PMID: 34862585 PMCID: PMC9213614 DOI: 10.1007/s11357-021-00482-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 10/28/2021] [Indexed: 10/31/2022] Open
Abstract
Long-term exercise training has been considered as an effective strategy to counteract age-related hormonal declines and minimise muscle atrophy. However, human data relating circulating hormone levels with motor nerve function are scant. The aims of the study were to explore associations between circulating sex hormone levels and motor unit (MU) characteristics in older men, including masters athletes competing in endurance and power events. Forty-three older men (mean ± SD age: 69.9 ± 4.6 years) were studied based on competitive status. The serum concentrations of dehydroepiandrosterone (DHEA), total testosterone (T) and estradiol were quantified using liquid chromatography mass spectrometry. Intramuscular electromyographic signals were recorded from vastus lateralis (VL) during 25% of maximum voluntary isometric contractions and processed to extract MU firing rate (FR), and motor unit potential (MUP) features. After adjusting for athletic status, MU FR was positively associated with DHEA levels (p = 0.019). Higher testosterone and estradiol were associated with lower MUP complexity; these relationships remained significant after adjusting for athletic status (p = 0.006 and p = 0.019, respectively). Circulating DHEA was positively associated with MU firing rate in these older men. Higher testosterone levels were associated with reduced MUP complexity, indicating reduced electrophysiological temporal dispersion, which is related to decreased differences in conduction times along axonal branches and/or MU fibres. Although evident in males only, this work highlights the potential of hormone administration as a therapeutic interventional strategy specifically targeting human motor units in older age.
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Affiliation(s)
- Yuxiao Guo
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, School of Medicine, University of Nottingham, Nottingham, UK
| | - Jessica Piasecki
- Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research Centre, Nottingham Trent University, Nottingham, UK
| | - Agnieszka Swiecicka
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Department of Basic and Clinical Sciences, University of Nicosia Medical School, Nicosia, Cyprus
| | - Alex Ireland
- Department of Sport and Exercise Sciences, Musculoskeletal Science and Sports Medicine Research Centre, Manchester Metropolitan University, Manchester, UK
| | - Bethan E. Phillips
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, School of Medicine, University of Nottingham, Nottingham, UK
| | - Philip J. Atherton
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, School of Medicine, University of Nottingham, Nottingham, UK
| | - Daniel Stashuk
- Department of Systems Design Engineering, University of Waterloo, Waterloo, ON Canada
| | - Martin K. Rutter
- Division of Diabetes, Endocrinology and Gastroenterology, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - Jamie S. McPhee
- Department of Sport and Exercise Sciences, Musculoskeletal Science and Sports Medicine Research Centre, Manchester Metropolitan University, Manchester, UK
| | - Mathew Piasecki
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, School of Medicine, University of Nottingham, Nottingham, UK
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15
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Effects of Endurance Cycling on Mechanomyographic Median Power Frequency of the Vastus Lateralis. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12105213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
This study examined the effects of cycling training on mechanomyographic median power frequency (MMGMDF)–torque relationships of the vastus lateralis (VL). Ten males (Age ± SD; 20.20 ± 1.87 years) and 14 females (21.93 ± 5.33 years) performed isometric trapezoidal muscle actions with the knee extensors at 40% maximal voluntary contraction (MVC) before (PRE) and following 10 weeks of cycling training at the same absolute submaximal torque as pre-training (POSTABS). MMGMDF–torque relationships (increasing and decreasing segment) were log-transformed and b terms (slopes) were calculated. MMGMDF was averaged during steady torque. For POSTABS, the b terms for the females (0.133 ± 0.190) were greater than for the males (−0.083 ± 0.200; p = 0.013) and compared to PRE (0.008 ± 0.161; p = 0.036). At PRE, the b terms for the linearly increasing-muscle action (0.123 ± 0.192) were greater compared to the linearly decreasing-muscle action (−0.061 ± 0.188; p < 0.001), whereas no differences existed between muscle actions for POSTABS (p > 0.05). In conclusion, 10 weeks of cycling training resulted in different motor unit (MU) control strategies between sexes and altered MU control strategies between muscle actions for the VL during a moderate-intensity contraction.
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16
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Power KE, Lockyer EJ, Botter A, Vieira T, Button DC. Endurance-exercise training adaptations in spinal motoneurones: potential functional relevance to locomotor output and assessment in humans. Eur J Appl Physiol 2022; 122:1367-1381. [PMID: 35226169 DOI: 10.1007/s00421-022-04918-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 02/11/2022] [Indexed: 12/14/2022]
Abstract
It is clear from non-human animal work that spinal motoneurones undergo endurance training (chronic) and locomotor (acute) related changes in their electrical properties and thus their ability to fire action potentials in response to synaptic input. The functional implications of these changes, however, are speculative. In humans, data suggests that similar chronic and acute changes in motoneurone excitability may occur, though the work is limited due to technical constraints. To examine the potential influence of chronic changes in human motoneurone excitability on the acute changes that occur during locomotor output, we must develop more sophisticated recording techniques or adapt our current methods. In this review, we briefly discuss chronic and acute changes in motoneurone excitability arising from non-human and human work. We then discuss the potential interaction effects of chronic and acute changes in motoneurone excitability and the potential impact on locomotor output. Finally, we discuss the use of high-density surface electromyogram recordings to examine human motor unit firing patterns and thus, indirectly, motoneurone excitability. The assessment of single motor units from high-density recording is mainly limited to tonic motor outputs and minimally dynamic motor output such as postural sway. Adapting this technology for use during locomotor outputs would allow us to gain a better understanding of the potential functional implications of endurance training-induced changes in human motoneurone excitability on motor output.
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Affiliation(s)
- Kevin E Power
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada. .,Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada.
| | - Evan J Lockyer
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada.,Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Alberto Botter
- Laboratory for Engineering of the Neuromuscular System (LISiN), Department of Electronics and Telecommunication, Politecnico di Torino, Turin, Italy.,PoliToBIOMed Lab, Politecnico di Torino, Turin, Italy
| | - Taian Vieira
- Laboratory for Engineering of the Neuromuscular System (LISiN), Department of Electronics and Telecommunication, Politecnico di Torino, Turin, Italy.,PoliToBIOMed Lab, Politecnico di Torino, Turin, Italy
| | - Duane C Button
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada.,Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada
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17
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Elgueta-Cancino E, Evans E, Martinez-Valdes E, Falla D. The Effect of Resistance Training on Motor Unit Firing Properties: A Systematic Review and Meta-Analysis. Front Physiol 2022; 13:817631. [PMID: 35295567 PMCID: PMC8918924 DOI: 10.3389/fphys.2022.817631] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 01/24/2022] [Indexed: 11/13/2022] Open
Abstract
While neural changes are thought to be responsible for early increases in strength following resistance training (RT), the exact changes in motor unit (MU) firing properties remain unclear. This review aims to synthesize the available evidence on the effect of RT on MU firing properties. MEDLINE (OVID interface), EMBASE (OVID interface), Web of Science (all databases), Cochrane Library, EBSCO CINAHL Plus, PubMed, and EBSCO SportDiscus were searched from inception until June 2021. Randomized controlled trials and non-randomized studies of interventions that compared RT to no intervention (control) were included. Two reviewers independently extracted data from each trial, assessed the risk of bias and rated the cumulative quality of evidence. Motor unit discharge rate (MUDR), motor unit recruitment threshold (MURT), motor unit discharge rate variability (MUDRV), MU discharge rate at recruitment vs. recruitment threshold relationship, and MU discharge rate vs. recruitment threshold relationship were assessed. Seven trials including 167 participants met the inclusion criteria. Meta-analysis (four studies) revealed that MUDR did not change significantly (P = 0.43), but with considerable heterogeneity likely to be present (I2 = 91). Low to moderate evidence supports changes in MUDRV, MUDR at recruitment vs. recruitment threshold relationship, and the MUDR vs. recruitment threshold relationship. Overall, this systematic review revealed that there is a lack of high-quality evidence for the effect of RT on MU firing properties. Heterogeneity across studies undermines the quality of the evidence for multiple outcomes and affects the conclusions that can be drawn.
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18
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Molinari T, Molinari T, Rabello R, Rodrigues R. Effects of 8 weeks of high-intensity interval training or resistance training on muscle strength, muscle power and cardiorespiratory responses in trained young men. SPORT SCIENCES FOR HEALTH 2022. [DOI: 10.1007/s11332-021-00872-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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19
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Trevino MA, Dimmick HL, Parra ME, Sterczala AJ, Miller JD, Deckert JA, Gallagher PM, Fry AC, Weir JP, Herda TJ. Effects of continuous cycling training on motor unit firing rates, input excitation, and myosin heavy chain of the vastus lateralis in sedentary females. Exp Brain Res 2022; 240:825-839. [DOI: 10.1007/s00221-021-06278-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 11/13/2021] [Indexed: 11/25/2022]
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20
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Jenkins ND, Miramonti AA, Hill EC, Smith CM, Cochrane-Snyman KC, Housh TJ, Cramer JT. Mechanomyographic Amplitude Is Sensitive to Load-Dependent Neuromuscular Adaptations in Response to Resistance Training. J Strength Cond Res 2021; 35:3265-3269. [DOI: 10.1519/jsc.0000000000003276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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21
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Tavoian D, Russ DW, Law TD, Simon JE, Chase PJ, Guseman EH, Clark BC. Effects of Three Different Exercise Strategies for Optimizing Aerobic Capacity and Skeletal Muscle Performance in Older Adults: A Pilot Study. J Frailty Aging 2021; 10:357-360. [PMID: 34549251 PMCID: PMC8114968 DOI: 10.14283/jfa.2021.21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
This Brief Report describes a pilot study of the effect of 12 weeks of stationary bicycle high-intensity interval training, stationary bicycle moderate-intensity continuous training, and resistance training on cardiorespiratory, muscular, and physical function measures in insufficiently-active older adults (N=14; 66.4±3.9 years; 3 male, 11 female). After baseline testing, participants were randomly assigned to one of the exercise groups. High-intensity interval training and moderate-intensity continuous training had small-to-large effect sizes on cardiorespiratory/endurance and physical function measures, but very small effect sizes on muscular measures. Resistance training had small-to-large effect sizes on cardiorespiratory, muscular, and physical function measures. This pilot study should be interpreted cautiously, but findings suggest that resistance exercise may be the most effective of the three studied exercise strategies for older adults as it can induce beneficial adaptations across multiple domains. These effect sizes can be used to determine optimal sample sizes for future investigations.
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Affiliation(s)
- D Tavoian
- Dallin Tavoian, Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, Athens, USA,
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22
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Escriche-Escuder A, Cuesta-Vargas AI, Casaña J. Effect of a common exercise programme with an individualised progression criterion based on the measurement of neuromuscular capacity versus current best practice for lower limb tendinopathies (MaLaGa trial): a protocol for a randomised clinical trial. BMJ Open 2021; 11:e046729. [PMID: 34404699 PMCID: PMC8372811 DOI: 10.1136/bmjopen-2020-046729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
INTRODUCTION High-load resistance training has shown positive effects in pain and function in lower limb tendinopathies. However, some authors suggest that current exercise programmes produce an increase in tolerance to load and exercise in general but without fixing some existing issues in tendinopathy. This may indicate the need to include training aspects not currently taken into account in the current programmes. The main objective of this study will be to compare the effect of a common exercise protocol for the three predominant lower limb tendinopathies (Achilles, patellar and gluteal), based on an individualised control of the dose and training of specific aspects of the neuromuscular system versus the current best practice for each location. METHODS AND ANALYSIS This study will be conducted among people with mid-portion Achilles, patellar or gluteal tendinopathy. The participants allocated to the experimental group will perform a 14-week innovative common therapeutic exercise programme. Participants allocated to the control group will carry out a 14-week exercise programme based on the best current practice for each of the studied locations. The Victorian Institute of Sports Assessment questionnaire will be considered the primary outcome. Pain, central sensitisation, fear avoidance behaviour, quality of life, treatment satisfaction, lower-limb strength and function, and high-density electromyography profile will be evaluated as secondary outcomes. Outcomes will be assessed at baseline, 7 weeks, after the intervention (week 14), 26 weeks and 52 weeks. ETHICS AND DISSEMINATION The study has been approved by the Portal de Ética de la Investigación Biomédica de Andalucía Ethics Committee (1221-N-19). All participants will be informed about the purpose and content of the study and written informed consent will be completed. The results of this study will be published in a peer-reviewed journal and will be disseminated electronically and in print. TRIAL REGISTRATION NUMBER NCT03853122; Pre-results.
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Affiliation(s)
- Adrian Escriche-Escuder
- Department of Physiotherapy, University of Malaga, Malaga, Spain
- Grupo Clinimetría (F-14), Instituto de Investigación Biomédica de Málaga (IBIMA), Malaga, Spain
| | - Antonio I Cuesta-Vargas
- Department of Physiotherapy, University of Malaga, Malaga, Spain
- Grupo Clinimetría (F-14), Instituto de Investigación Biomédica de Málaga (IBIMA), Malaga, Spain
- Health, Queensland University Technology, Brisbane, Queensland, Australia
| | - Jose Casaña
- Department of Physiotherapy, University of Valencia, Valencia, Spain
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Telles GD, Libardi CA, Conceição MS, Vechin FC, Lixandrão ME, DE Andrade ALL, Guedes DN, Ugrinowitsch C, Camera DM. Time Course of Skeletal Muscle miRNA Expression after Resistance, High-Intensity Interval, and Concurrent Exercise. Med Sci Sports Exerc 2021; 53:1708-1718. [PMID: 33731656 DOI: 10.1249/mss.0000000000002632] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
INTRODUCTION Exercise-induced microRNA (miRNA) expression has been implicated in the regulation of skeletal muscle plasticity. However, the specificity and acute time course in miRNA expression after divergent exercise modes are unknown. In a randomized crossover design, we compared the acute expression profile of eight skeletal muscle miRNAs previously reported to be involved in skeletal muscle development, growth, and maintenance after a bout of either resistance exercise (RE), high-intensity interval exercise (HIIE), and concurrent resistance and high-intensity interval exercises (CE). METHODS Nine untrained young men (23.9 ± 2.8 yr, 70.1 ± 14.9 kg, 177.2 ± 3.0 cm, 41.4 ± 5.2 mL·kg-1·min-1) underwent a counterbalanced crossover design in which they performed bouts of RE (2 × 10 repetitions maximum 45° leg press and leg extension exercises), HIEE (12 × 1-min sprints at V˙O2peak with 1-min rest intervals between sprints), and CE (RE followed by HIIE), separated by 1 wk. Vastus lateralis biopsies were harvested immediately before (Pre) and immediately (0 h), 4 h, and 8 h after each exercise bout. RESULTS There were similar increases (main effect of time; P < 0.05) in miR-1-3p, miR-133a-3p, miR-133b, miR-181a-3p, and miR-486 expression at 8 h from Pre with all exercise modes. Besides a main effect of time, miR-23a-3p and miR-206 presented a main effect of condition with lower expression after HIIE compared with RE and CE. CONCLUSIONS Select miRNAs (miR-1-3p, miR-133a-3p, miR-133b, miR-23a-3p, miR-181a-3p, miR-206, miR-486) do not exhibit an expression specificity in the acute recovery period after a single bout of RE, HIIE, or CE in skeletal muscle. Our data also indicate that RE has a higher effect on the expression of miR-23a-3p and miR-206 than HIIE. As upregulation of these miRNAs seems to be confined to the 8-h period after exercise, this may subsequently affect the expression patterns of target mRNAs forming the basis of exercise-induced adaptive responses.
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Affiliation(s)
- Guilherme Defante Telles
- Laboratory of Neuromuscular Adaptations to Strength Training, School of Physical Education and Sport, University of São Paulo (USP), São Paulo, São Paulo, BRAZIL
| | - Cleiton Augusto Libardi
- MUSCULAB-Laboratory of Neuromuscular Adaptations to Resistance Training, Department of Physical Education, Federal University of São Carlos-UFSCar, São Carlos, São Paulo, BRAZIL
| | - Miguel Soares Conceição
- Laboratory of Neuromuscular Adaptations to Strength Training, School of Physical Education and Sport, University of São Paulo (USP), São Paulo, São Paulo, BRAZIL
| | - Felipe Cassaro Vechin
- Laboratory of Neuromuscular Adaptations to Strength Training, School of Physical Education and Sport, University of São Paulo (USP), São Paulo, São Paulo, BRAZIL
| | - Manoel Emílio Lixandrão
- Laboratory of Neuromuscular Adaptations to Strength Training, School of Physical Education and Sport, University of São Paulo (USP), São Paulo, São Paulo, BRAZIL
| | | | | | - Carlos Ugrinowitsch
- Laboratory of Neuromuscular Adaptations to Strength Training, School of Physical Education and Sport, University of São Paulo (USP), São Paulo, São Paulo, BRAZIL
| | - Donny Michael Camera
- Department of Health and Medical Sciences, Swinburne University, Melbourne, Victoria, AUSTRALIA
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Lulic-Kuryllo T, Thompson CK, Jiang N, Negro F, Dickerson CR. Neural control of the healthy pectoralis major from low-to-moderate isometric contractions. J Neurophysiol 2021; 126:213-226. [PMID: 34107220 DOI: 10.1152/jn.00046.2021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The pectoralis major critically enables arm movement in several directions. However, its neural control remains unknown. High-density electromyography (HD-sEMG) was acquired from the pectoralis major in two sets of experiments in healthy young adults. Participants performed ramp-and-hold isometric contractions in: adduction, internal rotation, flexion, and horizontal adduction at three force levels: 15%, 25%, and 50% scaled to task-specific maximal voluntary force (MVF). HD-sEMG signals were decomposed into motor unit spike trains using a convolutive blind source separation algorithm and matched across force levels using a motor unit matching algorithm. The mean discharge rate and coefficient of variation were quantified across the hold and compared between 15% and 25% MVF across all tasks, whereas comparisons between 25% and 50% MVF were made where available. Mean motor unit discharge rate was not significantly different between 15% and 25% MVF (all P > 0.05) across all tasks or between 25% and 50% MVF in horizontal adduction (P = 0.11), indicating an apparent saturation across force levels and the absence of rate coding. These findings suggest that the pectoralis major likely relies on motor unit recruitment to increase force, providing first-line evidence of motor unit recruitment in this muscle and paving the way for more deliberate investigations of the pectoralis major involvement in shoulder function.NEW & NOTEWORTHY This work is the first to investigate the relative contribution of rate coding and motor unit recruitment in the pectoralis major muscle in several functionally relevant tasks and across varying force levels in healthy adults. Our results demonstrate the absence of motor unit rate coding with an increase in EMG amplitude with increases in force level in all tasks examined, indicating that the pectoralis major relies on motor unit recruitment to increase force.
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Affiliation(s)
- Tea Lulic-Kuryllo
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Christopher K Thompson
- Department of Health and Rehabilitation Sciences, Temple University, Philadelphia, Pennsylvania
| | - Ning Jiang
- Department of Systems Design Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - Francesco Negro
- Department of Clinical and Experimental Sciences, Università degli Studi di Brescia, Brescia, Italy
| | - Clark R Dickerson
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
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25
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Callahan MJ, Parr EB, Hawley JA, Camera DM. Can High-Intensity Interval Training Promote Skeletal Muscle Anabolism? Sports Med 2021; 51:405-421. [PMID: 33512698 DOI: 10.1007/s40279-020-01397-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Exercise training in combination with optimal nutritional support is an effective strategy to maintain or increase skeletal muscle mass. A single bout of resistance exercise undertaken with adequate protein availability increases rates of muscle protein synthesis and, when repeated over weeks and months, leads to increased muscle fiber size. While resistance-based training is considered the 'gold standard' for promoting muscle hypertrophy, other modes of exercise may be able to promote gains in muscle mass. High-intensity interval training (HIIT) comprises short bouts of exercise at or above the power output/speed that elicits individual maximal aerobic capacity, placing high tensile stress on skeletal muscle, and somewhat resembling the demands of resistance exercise. While HIIT induces rapid increases in skeletal muscle oxidative capacity, the anabolic potential of HIIT for promoting concurrent gains in muscle mass and cardiorespiratory fitness has received less scientific inquiry. In this review, we discuss studies that have determined muscle growth responses after HIIT, with a focus on molecular responses, that provide a rationale for HIIT to be implemented among populations who are susceptible to muscle loss (e.g. middle-aged or older adults) and/or in clinical settings (e.g. pre- or post-surgery).
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Affiliation(s)
- Marcus J Callahan
- Exercise and Nutrition Research Program, Mary MacKillop Institute for Health Research, Australian Catholic University, 215 Spring street, Melbourne, VIC, 3000, Australia
| | - Evelyn B Parr
- Exercise and Nutrition Research Program, Mary MacKillop Institute for Health Research, Australian Catholic University, 215 Spring street, Melbourne, VIC, 3000, Australia
| | - John A Hawley
- Exercise and Nutrition Research Program, Mary MacKillop Institute for Health Research, Australian Catholic University, 215 Spring street, Melbourne, VIC, 3000, Australia.
| | - Donny M Camera
- Department of Health and Medical Sciences, Swinburne University of Technology, Melbourne, VIC, Australia
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26
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Endurance training alters motor unit activation strategies for the vastus lateralis, yet sex-related differences and relationships with muscle size remain. Eur J Appl Physiol 2021; 121:1367-1377. [PMID: 33604695 DOI: 10.1007/s00421-021-04622-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 02/05/2021] [Indexed: 10/22/2022]
Abstract
PURPOSE To examine the effects of 10 weeks of endurance cycling training on mechanomyographic amplitude (MMGRMS)-torque relationships and muscle cross-sectional area (mCSA) of the vastus lateralis (VL) for 10 sedentary males (Age ± SD; 20.2 ± 1.9 years) and 14 sedentary females (21.9 ± 5.3 years). METHODS Participants performed maximal voluntary contractions (MVCs) and an isometric ramp up muscle action to 70% MVC of the knee extensors before (PRE) and after training at the same absolute pre-treatment submaximal torque (POSTABS). MMG was recorded from the VL and b terms were calculated from the natural log-transformed MMGRMS-torque relationships for each subject. mCSA was determined with ultrasonography. RESULTS Cycling decreased MVCs from pre- (168.10 ± 58.49 Nm) to post-training (160.78 ± 58.39 Nm; p = 0.005) without changes in mCSA. The b terms were greater for POSTABS (0.623 ± 0.204) than PRE (0.540 ± 0.226; p = 0.012) and for males (0.717 ± 0.171) than females (0.484 ± 0.168; p = 0.003). mCSA was correlated with the b terms for PRE (p < 0.001, r = 0.674) and POSTABS (p = 0.020, r = 0.471). CONCLUSION The decrease in MVC and increase in MMGRMS (b terms) post-training suggests increased motor unit (MU) recruitment to match pre-training torques. The greater acceleration in the b terms by males may reflect sex-related differences in fiber-type area. MMGRMS-torque relationships during a high-intensity contraction provided insight on MU activation strategies following endurance training and between sexes. Furthermore, the findings suggest a relationship between MMGRMS and muscle size.
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Nugent FJ, Vinther A, McGregor A, Thornton JS, Wilkie K, Wilson F. The relationship between rowing-related low back pain and rowing biomechanics: a systematic review. Br J Sports Med 2021; 55:bjsports-2020-102533. [PMID: 33397675 DOI: 10.1136/bjsports-2020-102533] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/16/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND Low back pain (LBP) is common in rowers. Understanding rowing biomechanics may help facilitate prevention and improve rehabilitation. OBJECTIVES To define the kinematics and muscle activity of rowers and to compare with rowers with current or LBP history. DESIGN Systematic review. DATA SOURCES EMBASE, MEDLINE, Cumulative Index to Nursing and Allied Health Literature, Web of Science and Scopus from inception to December 2019. Grey literature was searched. STUDY ELIGIBILITY CRITERIA Experimental and non-experimental designs. METHODS Primary outcomes were kinematics and muscle activity. Modified Quality Index (QI) checklist was used. RESULTS 22 studies were included (429 participants). Modified QI score had a mean of 16.7/28 points (range: 15-21). Thirteen studies investigated kinematics and nine investigated muscle activity. Rowers without LBP ('healthy') have distinct kinematics (neutral or anterior pelvic rotation at the catch, greater hip range of motion, flatter low back spinal position at the finish) and muscle activity (trunk extensor dominant with less flexor activity). Rowers with LBP had relatively greater posterior pelvic rotation at the catch, greater hip extension at the finish and less efficient trunk muscle activity. In both groups fatigue results in increased lumbar spine flexion at the catch, which is greater on the ergometer. There is insufficient evidence to recommend one ergometer type (fixed vs dynamic) over the other to avoid LBP. Trunk asymmetries are not associated with LBP in rowers. CONCLUSION Improving clinicians' and coaches' understanding of safe and effective rowing biomechanics, particularly of the spine, pelvis and hips may be an important strategy in reducing incidence and burden of LBP.
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Affiliation(s)
- Frank James Nugent
- Physical Education and Sport Sciences Department, Faculty of Education and Health Sciences, University of Limerick, Limerick, Ireland
- Sport and Human Performance Research Cluster, Health Research Institute, University of Limerick, Limerick, Ireland
| | - Anders Vinther
- Department of Physiotherapy and Occupational Therapy, Herlev Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Alison McGregor
- Department of Surgery and Cancer, Imperial College London, London, UK
| | - Jane S Thornton
- Western Centre for Public Health and Family Medicine, University of Western Ontario, London, Ontario, Canada
| | - Kellie Wilkie
- Bodysystem Physiotherapy, Hobart, Tasmania, Australia
| | - Fiona Wilson
- Discipline of Physiotherapy, School of Medicine, Trinity College Dublin, Dublin, Ireland
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28
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Piasecki J, Inns TB, Bass JJ, Scott R, Stashuk DW, Phillips BE, Atherton PJ, Piasecki M. Influence of sex on the age-related adaptations of neuromuscular function and motor unit properties in elite masters athletes. J Physiol 2021; 599:193-205. [PMID: 33006148 DOI: 10.1113/jp280679] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 09/24/2020] [Indexed: 12/30/2022] Open
Abstract
KEY POINTS Masters athletes maintain high levels of activity into older age and allow an examination of the effects of aging dissociated from the effects of increased sedentary behaviour. Evidence suggests masters athletes are more successful at motor unit remodelling, the reinnervation of denervated fibres acting to preserve muscle fibre number, but little data are available in females. Here we used intramuscular electromyography to demonstrate that motor units sampled from the tibialis anterior show indications of remodelling from middle into older age and which does not differ between males and females. The age-related trajectory of motor unit discharge characteristic differs according to sex, with female athletes progressing to a slower firing pattern that was not observed in males. Our findings indicate motor unit remodelling from middle to older age occurs to a similar extent in male and female athletes, with discharge rates progressively slowing in females only. ABSTRACT Motor unit (MU) remodelling acts to minimise loss of muscle fibres following denervation in older age, which may be more successful in masters athletes. Evidence suggests performance and neuromuscular function decline with age in this population, although the majority of studies have focused on males, with little available data on female athletes. Functional assessments of strength, balance and motor control were performed in 30 masters athletes (16 male) aged 44-83 years. Intramuscular needle electrodes were used to sample individual motor unit potentials (MUPs) and near-fibre MUPs in the tibialis anterior (TA) during isometric contractions at 25% maximum voluntary contraction, and used to determine discharge characteristics (firing rate, variability) and biomarkers of peripheral MU remodelling (MUP size, complexity, stability). Multilevel mixed-effects linear regression models examined effects of age and sex. All aspects of neuromuscular function deteriorated with age (P < 0.05) with no age × sex interactions, although males were stronger (P < 0.001). Indicators of MU remodelling also progressively increased with age to a similar extent in both sexes (P < 0.05), whilst MU firing rate progressively decreased with age in females (p = 0.029), with a non-significant increase in males (p = 0.092). Masters athletes exhibit age-related declines in neuromuscular function that are largely equal across males and females. Notably, they also display features of MU remodelling with advancing age, probably acting to reduce muscle fibre loss. The age trajectory of MU firing rate assessed at a single contraction level differed between sexes, which may reflect a greater tendency for females to develop a slower muscle phenotype.
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Affiliation(s)
- Jessica Piasecki
- Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research Centre, School of Science and Technology, Nottingham Trent University, Nottingham, UK
| | - Thomas B Inns
- Clinical, Metabolic and Molecular Physiology, MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, UK
| | - Joseph J Bass
- Clinical, Metabolic and Molecular Physiology, MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, UK
| | - Reece Scott
- Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research Centre, School of Science and Technology, Nottingham Trent University, Nottingham, UK
| | - Daniel W Stashuk
- Department of Systems Design Engineering, University of Waterloo, Ontario, Canada
| | - Bethan E Phillips
- Clinical, Metabolic and Molecular Physiology, MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, UK
| | - Philip J Atherton
- Clinical, Metabolic and Molecular Physiology, MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, UK
| | - Mathew Piasecki
- Clinical, Metabolic and Molecular Physiology, MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, UK
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Cogliati M, Cudicio A, Martinez-Valdes E, Tarperi C, Schena F, Orizio C, Negro F. Half marathon induces changes in central control and peripheral properties of individual motor units in master athletes. J Electromyogr Kinesiol 2020; 55:102472. [DOI: 10.1016/j.jelekin.2020.102472] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 09/08/2020] [Accepted: 09/11/2020] [Indexed: 11/30/2022] Open
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30
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Negro F, Bathon KE, Nguyen JN, Bannon CG, Orizio C, Hunter SK, Hyngstrom AS. Impaired Firing Behavior of Individually Tracked Paretic Motor Units During Fatiguing Contractions of the Dorsiflexors and Functional Implications Post Stroke. Front Neurol 2020; 11:540893. [PMID: 33192970 PMCID: PMC7658471 DOI: 10.3389/fneur.2020.540893] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 09/25/2020] [Indexed: 11/13/2022] Open
Abstract
Introduction: This study quantified stroke-related changes in the following: (1) the averaged discharge rate of motor units (individually tracked and untracked) identified from high-density electromyography (HD-EMG) recordings, (2) global muscle EMG properties of the dorsiflexors during a fatiguing contraction, and the relationship between task endurance and measures of leg function. Methods: Ten individuals with chronic stroke performed a sustained sub-maximal, isometric, fatiguing dorsiflexion contraction in paretic and non-paretic legs. Motor-unit firing behavior, task duration, maximal voluntary contraction strength (MVC), and clinical measures of leg function were obtained. Results: Compared to the non-paretic leg, the paretic leg task duration was shorter, and there was a larger exercise-related reduction in motor unit global rates, individually tracked discharge rates, and overall magnitude of EMG. Task duration of the paretic leg was more predictive of walking speed and lower extremity Fugl-Meyer scores compared to the non-paretic leg. Discussion: Paretic leg muscle fatigability is increased post stroke. It is characterized by impaired rate coding and recruitment and relates to measures of motor function.
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Affiliation(s)
- Francesco Negro
- Department of Clinical and Experimental Sciences, Research Center for Neuromuscular Function and Adapted Physical Activity "Teresa Camplani", Università degli Studi di Brescia, Brescia, Italy
| | - Kathleen E Bathon
- Uniformed Services, University of Health Sciences, Bethesda, MD, United States
| | - Jennifer N Nguyen
- Department of Physical Medicine and Rehabilitation, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Cassidy G Bannon
- Uniformed Services, University of Health Sciences, Bethesda, MD, United States
| | - Claudio Orizio
- Department of Clinical and Experimental Sciences, Research Center for Neuromuscular Function and Adapted Physical Activity "Teresa Camplani", Università degli Studi di Brescia, Brescia, Italy
| | - Sandra K Hunter
- Department of Physical Therapy, Marquette University, Milwaukee, WI, United States
| | - Allison S Hyngstrom
- Department of Physical Therapy, Marquette University, Milwaukee, WI, United States
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31
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Hannaian SJ, Orlando MN, Abou Sawan S, Mazzulla M, West DWD, Moore DR. Protein Timing Does Not Affect Next-Day Recovery of Strength or Power but May Enhance Aerobic Adaptations to Short-Term Variable Intensity Exercise Training in Recreationally Active Males: A Pilot Study. Front Sports Act Living 2020; 2:568740. [PMID: 33345126 PMCID: PMC7739639 DOI: 10.3389/fspor.2020.568740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 09/10/2020] [Indexed: 12/24/2022] Open
Abstract
Background: Variable intensity training (VIT) characteristic of stop-and-go team sport exercise may reduce performance capacity when performed on successive days but also represent a strategy to induce rapid training-induced increases in exercise capacity. Although post-exercise protein enhances muscle protein synthesis, the timing of protein ingestion following variable intensity training (VIT) on next-day recovery and short-term performance adaptation is unknown. Purpose: To determine if immediate (IMM) as compared to delayed (DEL) protein ingestion supports greater acute recovery of exercise performance during successive days of VIT and/or supports chronic training adaptations. Methods: Sixteen habitually active men performed 5 consecutive days of variable intensity training (VIT) in the evening prior to consuming a beverage providing carbohydrate and whey protein (IMM; 0.7 g and 0.3 g/kg, respectively) or carbohydrates alone (DEL; 1 g/kg) with the reciprocal beverage consumed the following morning. Performance was assessed before each VIT (recovery) and 2 days after the final VIT (adaptation). Results: Five consecutive days of VIT progressively decreased anaerobic peak power (~7%) and muscle strength (MVC; ~8%) with no impact of protein timing. Following 2 days of recovery, VIT increased maximal voluntary contraction and predicted VO2peak by ~10 and ~5%, respectively, with a moderate beneficial effect of IMM on predicted VO2peak (ES = 0.78). Conclusion: Successive days of simulated team sport exercise decreases markers of next-day performance capacity with no effect of protein timing on acute recovery. However, practical VIT increases muscle strength and aerobic capacity in as little as 5 days with the latter potentially enhanced by immediate post-exercise protein consumption.
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Affiliation(s)
- Sarkis J Hannaian
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Mark N Orlando
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Sidney Abou Sawan
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Michael Mazzulla
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Daniel W D West
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Daniel R Moore
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
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Martinez-Valdes E, Negro F, Falla D, Dideriksen JL, Heckman CJ, Farina D. Inability to increase the neural drive to muscle is associated with task failure during submaximal contractions. J Neurophysiol 2020; 124:1110-1121. [DOI: 10.1152/jn.00447.2020] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Motor unit firing and contractile properties during a submaximal contraction until failure were assessed with a new tracking technique. Two distinct phases in firing behavior were observed, which compensated for changes in twitch area and predicted time to failure. However, the late increase in firing rate was below the rates attained in the absence of fatigue, which points to an inability of the central nervous system to sufficiently increase the neural drive to muscle with fatigue.
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Affiliation(s)
- Eduardo Martinez-Valdes
- Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Francesco Negro
- Department of Clinical and Experimental Sciences, Research Centre for Neuromuscular Function and Adapted Physical Activity “Teresa Camplani,” Università degli Studi di Brescia, Brescia, Italy
| | - Deborah Falla
- Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Jakob Lund Dideriksen
- Center for Sensory-Motor Interaction, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - C. J. Heckman
- Department of Physiology, Northwestern University, Chicago, Illinois
| | - Dario Farina
- Department of Bioengineering, Imperial College London, Royal School of Mines, London, United Kingdom
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33
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Dolci F, Kilding AE, Chivers P, Piggott B, Hart NH. High-Intensity Interval Training Shock Microcycle for Enhancing Sport Performance: A Brief Review. J Strength Cond Res 2020; 34:1188-1196. [PMID: 31904712 DOI: 10.1519/jsc.0000000000003499] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Dolci, F, Kilding, AE, Chivers, P, Piggott, B, and Hart, NH. High-intensity interval training shock microcycle for enhancing sport performance: A brief review. J Strength Cond Res 34(4): 1188-1196, 2020-High-intensity interval training (HIIT) is a powerful strategy to develop athletes' fitness and enhance endurance performance. Traditional HIIT interventions involve multiple microcycles (7-10 days long) of 2-3 HIIT sessions each, which have been commonly supported to improve athletic performance after a minimum period of 6 weeks training. Regardless of the efficacy of such an approach, in recent years, a higher frequency of HIIT sessions within a unique microcycle, commonly referred to as an HIIT shock microcycle, has been proposed as an alternative HIIT periodization strategy to induce greater and more efficient endurance adaptation in athletes. This review article provides an insight into this new HIIT periodization strategy by discussing (1) HIIT shock microcycle format and design; (2) the sustainability of this training strategy; (3) effects on performance and physiological parameters of endurance; and (4) potential mechanisms for improvements. Evidence advocates the sustainability and effectiveness of HIIT shock microcycle in different athletes to improve intermittent and continuous running/cycling performance and suggests mitochondria biogenesis as the main acute physiological adaptation following this intervention.
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Affiliation(s)
- Filippo Dolci
- School of Health Science, The University of Notre Dame Australia, Fremantle, Australia
| | - Andrew E Kilding
- Sports Performance Research Institute New Zealand, AUT University, Auckland, New Zealand
| | - Paola Chivers
- Institute for Health Research, The University of Notre Dame Australia, Fremantle, Australia.,Exercise Medicine Research Institute, Edith Cowan University, Perth, Australia; and
| | - Ben Piggott
- School of Health Science, The University of Notre Dame Australia, Fremantle, Australia
| | - Nicolas H Hart
- School of Health Science, The University of Notre Dame Australia, Fremantle, Australia.,Exercise Medicine Research Institute, Edith Cowan University, Perth, Australia; and.,School of Medical and Health Science, Edith Cowan University, Perth, Australia
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34
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High-intensity interval training on body composition, functional capacity and biochemical markers in healthy young versus older people. Exp Gerontol 2020; 141:111096. [PMID: 32971179 DOI: 10.1016/j.exger.2020.111096] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 12/31/2022]
Abstract
BACKGROUND The aim of the following study was to identify the effects of a 12-week high-intensity interval training (HIIT) program on the modification of parameters of body composition, functional capacity as well as lipid and glucose homeostasis markers in healthy young people versus older adults. DESIGN Experimental trial. METHODS Healthy young (YNG, 21 ± 1 years, BMI 26.01 ± 2.64 kg·m-2, n = 10) and older (OLD, 66 ± 5 years, BMI 27.43 ± 3.11 kg·m-2, n = 10) males were subjected to 12 weeks of HIIT. Prior to and immediately after the HIIT program, dual-energy X-ray absorptiometry, dominant leg strength one-repetition maximum (1-RM), maximal oxygen uptake (VO2max) and physical performance tests were performed. Blood samples were also taken. RESULTS Flexibility (P = 0.000), static balance (P = 0.004), timed up and go test (TUG) (P = 0.015), short physical performance battery (SPPB) (P = 0.005), dominant leg strength 1-RM (P = 0.012), and VO2max (P = 0.000) were better in YNG versus OLD. HIIT improved the % whole-body fat mass (P = 0.031), leg lean mass (P = 0.047), dominant leg strength 1-RM (P = 0.025), VO2max (P = 0.000), fasting cholesterol (P = 0.017) and fasting glucose (P = 0.006). TUG was improved by the training only in the OLD group (P = 0.016), but insulin (P = 0.002) and the homeostasis model assessment - insulin sensitivity (HOMA-IS) (P = 0.000) decreased only in the YNG group. HOMA-IS was correlated positive with BMI (R = 0.474, P = 0.035) and with whole-body fat mass (R = 0.517, P = 0.019). CONCLUSIONS HIIT for 12 weeks improves parameters of body composition, functional capacity and fasting serum lipid and glucose homeostasis markers in healthy young and older participants. Young people are shown as benefiting more.
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Bonilauri B, Dallagiovanna B. Long Non-coding RNAs Are Differentially Expressed After Different Exercise Training Programs. Front Physiol 2020; 11:567614. [PMID: 33071823 PMCID: PMC7533564 DOI: 10.3389/fphys.2020.567614] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 08/25/2020] [Indexed: 12/29/2022] Open
Abstract
Background Molecular regulation related to the health benefits of different exercise modes remains unclear. Long non-coding RNAs (lncRNAs) have emerged as an RNA class with regulatory functions in health and diseases. Here, we analyzed the expression of lncRNAs after different exercise training programs and their possible modes of action related to physical exercise adaptations. Methods Public high-throughput RNA-seq data (skeletal muscle biopsies) were downloaded, and bioinformatics analysis was performed. We primarily analyzed data reports of 12 weeks of resistance training (RT), high-intensity interval training (HIIT), and combined (CT) exercise training. In addition, we analyzed data from 8 weeks of endurance training (ET). Differential expression analysis of lncRNAs was performed, and an adjusted P-value < 0.1 and log2 (fold change) ≥0.5 or ≤-0.5 were set as the cutoff values to identify differentially expressed lncRNAs (DELs). Results We identified 204 DELs after 12 weeks of HIIT, 43 DELs after RT, and 15 DELs after CT. Moreover, 52 lncRNAs were differentially expressed after 8 weeks of ET. The lncRNA expression pattern after physical exercise was very specific, with distinct expression profiles for the different training programs, where few lncRNAs were common among the exercise types. LncRNAs may regulate molecular responses to exercise, such as collagen fibril organization, extracellular matrix organization, myoblast and plasma membrane fusion, skeletal muscle contraction, synaptic transmission, PI3K and TORC regulation, autophagy, and angiogenesis. Conclusion For the first time, we show that lncRNAs are differentially expressed in skeletal muscle after different physical exercise programs, and these lncRNAs may act in various biological processes related to physical activity adaptations.
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Affiliation(s)
- Bernardo Bonilauri
- Laboratory of Basic Biology of Stem Cells (LABCET), Carlos Chagas Institute - FIOCRUZ-PR, Curitiba, Brazil
| | - Bruno Dallagiovanna
- Laboratory of Basic Biology of Stem Cells (LABCET), Carlos Chagas Institute - FIOCRUZ-PR, Curitiba, Brazil
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Aagaard P, Bojsen-Møller J, Lundbye-Jensen J. Assessment of Neuroplasticity With Strength Training. Exerc Sport Sci Rev 2020; 48:151-162. [DOI: 10.1249/jes.0000000000000229] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Thom G, Kavaliauskas M, Babraj J. Changes in lactate kinetics underpin soccer performance adaptations to cycling-based sprint interval training. Eur J Sport Sci 2020; 20:486-494. [PMID: 31232639 DOI: 10.1080/17461391.2019.1635650] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
In adolescent soccer, 23% of the distance covers happens at speeds above onset of blood lactate accumulation which suggests that lactate kinetics may be important for soccer performance. We sought to determine the effectiveness of sprint interval training (SIT) on changing performance and lactate kinetics in adolescent soccer players. Thirteen elite soccer academy players (age 15 ± 0.5y) underwent baseline testing (0-10 m and 10-20 m sprint performance, Wingate anaerobic Test (WaNT) with blood lactate measurements and incremental VO2 peak test) before being allocated to control or SIT group. The control group maintained training whilst the HIT group carried out twice-weekly all-out effort cycle sprints consisting of 6 × 10 s sprint with 80 s recovery. There were significant time x group interactions for 10-20 m sprint time (Control pre: 1.32 ± 0.07 s post: 1.35 ± 0.08 s; SIT pre: 1.29 ± 0.04 s post: 1.25 ± 0.04 s; p = 0.01), Peak Power (Control pre: 13.1 ± 1.3 W.kg-1 post: 13.2 ± 1.47 W.kg-1; SIT pre: 12.4 ± 1.3 W.kg-1 post: 15.3 ± 0.7 W.kg-1; p = 0.01) and time to exhaustion (Control pre: 596 ± 62 s post: 562 ± 85 s; SIT pre: 655 ± 54 s post: 688 ± 55 s; p = 0.001). The changes in performance were significantly correlated to changes in lactate kinetics (power: r = 0.55; 10-20 m speed: r = -0.54; time to exhaustion: r = 0.55). Therefore, cycle based SIT is an effective training paradigm for elite adolescent soccer players and the improvements in performance are associated with changes in lactate kinetics.
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Affiliation(s)
- Graham Thom
- Division of Sport and Exercise Science, Abertay University, Dundee, Scotland
| | - Mykolas Kavaliauskas
- School of Applied Sciences, Sport, Exercise and Health Sciences, Edinburgh Napier University, Edinburgh, Scotland
| | - John Babraj
- Division of Sport and Exercise Science, Abertay University, Dundee, Scotland
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Martinez-Valdes E, Wilson F, Fleming N, McDonnell SJ, Horgan A, Falla D. Rowers with a recent history of low back pain engage different regions of the lumbar erector spinae during rowing. J Sci Med Sport 2019; 22:1206-1212. [DOI: 10.1016/j.jsams.2019.07.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 06/13/2019] [Accepted: 07/16/2019] [Indexed: 11/16/2022]
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Tavoian D, Russ DW, Law TD, Simon JE, Chase PJ, Guseman EH, Clark BC. A Randomized Clinical Trial Comparing Three Different Exercise Strategies for Optimizing Aerobic Capacity and Skeletal Muscle Performance in Older Adults: Protocol for the DART Study. Front Med (Lausanne) 2019; 6:236. [PMID: 31750307 PMCID: PMC6842975 DOI: 10.3389/fmed.2019.00236] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 10/07/2019] [Indexed: 12/25/2022] Open
Abstract
Background: Age-related declines in physical function lead to decreased independence and higher healthcare costs. Individuals who meet the endurance and resistance exercise recommendations can improve their physical function and overall fitness, even into their ninth decade. However, most older adults do not exercise regularly, and the majority of those who do only perform one type of exercise, and in doing so are not getting the benefits of endurance or resistance exercise. Herein we present the study protocol for a randomized clinical trial that will investigate the potential for high-intensity interval training (HIIT) to improve maximal oxygen consumption, muscular power, and muscle volume (primary outcomes), as well as body composition, 6-min walk distance, and muscular strength and endurance (secondary outcomes). Methods and Analysis: This is a single-site, single-blinded, randomized clinical trial. A minimum of 24 and maximum of 30 subjects aged 60-75 that are generally healthy but insufficiently active will be randomized. After completion of baseline assessments, participants will be randomized in a 1:1:1 ratio to participate in one of three 12-week exercise programs: stationary bicycle HIIT, stationary bicycle moderate-intensity continuous training (MICT), or resistance training. Repeat assessments will be taken immediately post intervention. Discussion: This study will examine the potential for stationary bicycle HIIT to result in both cardiorespiratory and muscular adaptations in older adults. The results will provide important insights into the effectiveness of interval training, and potentially support a shift from volume-driven to intensity-driven exercise strategies for older adults. Clinical Trial Registration: This trial is registered with ClinicalTrials.gov (registration number: NCT03978572, date of registration June 7, 2019).
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Affiliation(s)
- Dallin Tavoian
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, United States
| | - David W Russ
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, United States.,Laboratory for Integrative Muscle Biology, Division of Physical Therapy, Ohio University, Athens, OH, United States
| | - Timothy D Law
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, United States
| | - Janet E Simon
- Division of Athletic Training, School of Applied Health Sciences and Wellness, Ohio University, Athens, OH, United States
| | - Paul J Chase
- Division of Exercise Physiology, School of Applied Health Sciences and Wellness, Ohio University, Athens, OH, United States
| | - Emily Hill Guseman
- Diabetes Institute, Ohio University, Athens, OH, United States.,Department of Family Medicine, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, United States
| | - Brian C Clark
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, United States.,Department of Biomedical Sciences, Ohio University, Athens, OH, United States
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Arvanitidis M, Falla D, Martinez-Valdes E. Can visual feedback on upper trapezius high-density surface electromyography increase time to task failure of an endurance task? J Electromyogr Kinesiol 2019; 49:102361. [PMID: 31605889 DOI: 10.1016/j.jelekin.2019.102361] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 09/27/2019] [Accepted: 09/30/2019] [Indexed: 10/25/2022] Open
Abstract
We investigate whether visual feedback on the spatial distribution of upper trapezius muscle activity can prolong time to task failure of sustained shoulder abduction. Surface electromyographic signals were acquired with a 13x5 grid of high-density electromyography (HDEMG) electrodes from the right upper trapezius muscle of 12 healthy volunteers as they performed sustained isometric shoulder abduction at 20% of their maximum voluntary contraction torque (MVC) until volitional exhaustion. Data were collected in two sessions; one with HDEMG visual feedback on the spatial distribution of upper trapezius activity and one without feedback. Although the HDEMG amplitude maps could be voluntarily modified by the participants during the feedback condition (significant shift in the barycenter of activity towards the cranial direction, P = 0.038), this did not influence endurance time (total endurance time with HDEMG feedback: 149.01 ± 77.07 s, no feedback 141.74 ± 60.93 s, P = 0.532). Future studies should assess whether endurance performance can be enhanced by allowing changes in arm position during the task (changing fiber tension-length relationships), by providing a more individual motor strategy, and/or by manipulating the colours used for the HDEMG maps (lighter colours for higher contraction intensities).
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Affiliation(s)
- Michail Arvanitidis
- Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, UK
| | - Deborah Falla
- Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, UK
| | - Eduardo Martinez-Valdes
- Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, UK.
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Boccia G, Martinez-Valdes E, Negro F, Rainoldi A, Falla D. Motor unit discharge rate and the estimated synaptic input to the vasti muscles is higher in open compared with closed kinetic chain exercise. J Appl Physiol (1985) 2019; 127:950-958. [DOI: 10.1152/japplphysiol.00310.2019] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Conflicting results have been reported on whether closed kinetic chain exercises (such as a leg press) may induce more balanced activation of vastus medialis (VM) and lateralis (VL) muscles compared with open kinetic chain exercise (such as pure knee extension). This study aimed to 1) compare between-vasti motor unit activity and 2) analyze the combined motor unit behavior from both muscles between open and closed kinetic chain exercises. Thirteen participants (four women, mean ± SD age: 27 ± 5 yr) performed isometric knee extension and leg press at 10, 30, 50, 70% of the maximum voluntary torque. High density surface EMG signals were recorded from the VM and VL and motor unit firings were automatically identified by convolutive blind source separation. We estimated the total synaptic input received by the two muscles by analyzing the difference in discharge rate from recruitment to target torque for motor units matched by recruitment threshold. When controlling for recruitment threshold and discharge rate at recruitment, the motor unit discharge rates were higher for knee extension compared with the leg press exercise at 50% [estimate = 1.2 pulses per second (pps), standard error (SE) = 0.3 pps, P = 0.0138] and 70% (estimate = 2.0 pps, SE = 0.3 pps, P = 0.0001) of maximal torque. However, no difference between the vasti muscles were detected in both exercises. The estimates of synaptic input to the muscles confirmed these results. In conclusion, the estimated synaptic input received by VM and VL was similar within and across exercises. However, both muscles had higher firing rates and estimated synaptic input at the highest torque levels during knee extension. Taken together, the results show that knee-extension is more suitable than leg-press exercise at increasing the concurrent activation of the vasti muscles. NEW & NOTEWORTHY There is a significant debate on whether open kinetic chain, single-joint knee extension exercise can influence the individual and combined activity of the vasti muscles compared with closed kinetic chain, multijoint leg press exercise. Here we show that attempting to change the contribution of either the vastus medialis or vastus lateralis via different forms of exercise does not seem to be a viable strategy. However, the adoption of open kinetic chain knee extension induces greater discharge rate and estimated synaptic input to both vasti muscles compared with the leg press.
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Affiliation(s)
- Gennaro Boccia
- Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom
- NeuroMuscularFunction Research Group, School of Exercise and Sport Sciences, Department of Medical Sciences, University of Turin, Turin, Italy
| | - Eduardo Martinez-Valdes
- Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Francesco Negro
- Department of Clinical and Experimental Sciences, Università degli Studi di Brescia, Brescia, Italy
| | - Alberto Rainoldi
- NeuroMuscularFunction Research Group, School of Exercise and Sport Sciences, Department of Medical Sciences, University of Turin, Turin, Italy
| | - Deborah Falla
- Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom
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What are the Acute Effects of Aerobic Exercise on Fractionated Response Time: A Systematic Review and Meta-analysis. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/s42978-019-0026-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Hurst C, Scott JPR, Weston KL, Weston M. High-Intensity Interval Training: A Potential Exercise Countermeasure During Human Spaceflight. Front Physiol 2019; 10:581. [PMID: 31191330 PMCID: PMC6541112 DOI: 10.3389/fphys.2019.00581] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 04/25/2019] [Indexed: 12/30/2022] Open
Abstract
High-intensity interval training (HIT) is an effective approach for improving a range of physiological markers associated with physical fitness. A considerable body of work has demonstrated substantial improvements in cardiorespiratory fitness following short-term training programmes, while emerging evidence suggests that HIT can positively impact aspects of neuromuscular fitness. Given the detrimental consequences of prolonged exposure to microgravity on both of these physiological systems, and the potential for HIT to impact multiple components of fitness simultaneously, HIT is an appealing exercise countermeasure during human spaceflight. As such, the primary aim of this mini review is to synthesize current terrestrial knowledge relating to the effectiveness of HIT for inducing improvements in cardiorespiratory and neuromuscular fitness. As exercise-induced fitness changes are typically influenced by the specific exercise protocol employed, we will consider the effect of manipulating programming variables, including exercise volume and intensity, when prescribing HIT. In addition, as the maintenance of HIT-induced fitness gains and the choice of exercise mode are important considerations for effective training prescription, these issues are also discussed. We conclude by evaluating the potential integration of HIT into future human spaceflight operations as a strategy to counteract the effects of microgravity.
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Affiliation(s)
- Christopher Hurst
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom.,NIHR Newcastle Biomedical Research Centre, Newcastle upon Tyne Hospitals NHS Foundation Trust and Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Jonathan P R Scott
- KBRwyle GmbH, Cologne, Germany.,Space Medicine Office, European Astronaut Centre, European Space Agency (ESA), Cologne, Germany
| | - Kathryn L Weston
- School of Health and Social Care, Teesside University, Middlesbrough, United Kingdom
| | - Matthew Weston
- School of Health and Social Care, Teesside University, Middlesbrough, United Kingdom
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Clark A, De La Rosa AB, DeRevere JL, Astorino TA. Effects of various interval training regimes on changes in maximal oxygen uptake, body composition, and muscular strength in sedentary women with obesity. Eur J Appl Physiol 2019; 119:879-888. [PMID: 30643959 DOI: 10.1007/s00421-019-04077-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Accepted: 01/09/2019] [Indexed: 12/13/2022]
Abstract
PURPOSE We determined the effects of two high-intensity interval training (HIIT) regimens [the traditional (TRAD) and periodized (PER)] on changes in maximal oxygen uptake (VO2max), body composition, and muscular strength in sedentary, obese women. METHODS Seventeen women (age and BMI = 37.5 ± 10.5 year and 39.1 ± 4.3 kg/m2) were randomized into a 6 week regime of TRAD or PER which consisted of three sessions per week, two in the laboratory, and one on their own. Pre- and post-training, VO2max, body composition, and muscular strength of the knee extensors (KE) and flexors (KF) were assessed via ramp cycling to exhaustion, air displacement plethysmography, and isokinetic dynamometry, respectively. RESULTS VO2max was increased by 4-5% in response to training (p = 0.045) with no group-by-time interaction (p = 0.79). Body mass, fat mass, and waist-to-hip ratio were unaltered (p > 0.05) in response to training, yet there was a significant change in percent body fat (p = 0.03), percent fat-free mass (p = 0.03), and absolute fat-free mass (p = 0.03) in TRAD but not PER. No change occurred in KE (p = 0.36) or KF torque (p = 0.75) in response to training and there was no group-by-time interaction (p > 0.05). CONCLUSIONS Low-volume HIIT improved VO2max and body composition but did not modify muscular strength, which suggests that obese women desiring to increase strength should initiate more intense HIIT or partake in formal resistance training.
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Affiliation(s)
- Amy Clark
- Department of Kinesiology, California State University, 333. S. Twin Oaks Valley Road, UNIV 320, San Marcos, CA, 92096-0001, USA
| | - Annie B De La Rosa
- Department of Kinesiology, California State University, 333. S. Twin Oaks Valley Road, UNIV 320, San Marcos, CA, 92096-0001, USA
| | - Jamie L DeRevere
- Department of Kinesiology, California State University, 333. S. Twin Oaks Valley Road, UNIV 320, San Marcos, CA, 92096-0001, USA
| | - Todd A Astorino
- Department of Kinesiology, California State University, 333. S. Twin Oaks Valley Road, UNIV 320, San Marcos, CA, 92096-0001, USA.
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Schaun GZ, Pinto SS, Brasil B, Nunes GN, Alberton CL. Neuromuscular adaptations to sixteen weeks of whole-body high-intensity interval training compared to ergometer-based interval and continuous training. J Sports Sci 2019; 37:1561-1569. [PMID: 30724683 DOI: 10.1080/02640414.2019.1576255] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The neuromuscular adaptations between ergometer-based high-intensity interval training (HIIT-T; n = 15), whole-body high-intensity interval training (HIIT-WB; n = 12) and moderate-intensity continuous training (MICT; n = 14) were compared in forty-one healthy men randomized to 16 weeks of training (3x per week). Two-way repeated measures analysis of variance (ANOVA) showed countermovement (CMJ) and squat (SJ) jump height (HIIT-T: 8.5 ± 13.3%; 3.1 ± 9.7%, HIIT-WB: 6.4 ± 9.8%, 10.4 ± 16.1% and MICT: 2.2 ± 9.5%; 4.4 ± 12.1%, respectively), SJ peak power (HIIT-T: 1.7 ± 3.9%; HIIT-WB : 6.4 ± 7.9%; MICT: 0.5 ± 6.5%) and CMJ rate of force development (HIIT-T: 58.1 ± 50.5%; HIIT-WB: 36.9 ± 54.2%; MICT: 38.4 ± 64.3%) improved similarly in all training groups (all p < 0.05). CMJ peak power increased only after HIIT-T (4.3 ± 5.5%) and HIIT-WB (4.5 ± 5.2%), while no differences were observed in both the rectus femoris and vastus lateralis maximal electromyographic amplitude. Finally, marked improvements were also observed in the number of repetitions in the HIIT-WB protocol at the eighth week, with no further improvement at the sixteenth week. These data suggest that 16 weeks of HIIT-WB is capable to improve neuromuscular function to a similar extent as HIIT-T and MICT.
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Affiliation(s)
- Gustavo Zaccaria Schaun
- a Neuromuscular Assessment Laboratory, Physical Education School , Federal University of Pelotas , Pelotas , Brazil
| | - Stephanie Santana Pinto
- a Neuromuscular Assessment Laboratory, Physical Education School , Federal University of Pelotas , Pelotas , Brazil
| | - Bruno Brasil
- a Neuromuscular Assessment Laboratory, Physical Education School , Federal University of Pelotas , Pelotas , Brazil
| | - Gabriela Neves Nunes
- a Neuromuscular Assessment Laboratory, Physical Education School , Federal University of Pelotas , Pelotas , Brazil
| | - Cristine Lima Alberton
- a Neuromuscular Assessment Laboratory, Physical Education School , Federal University of Pelotas , Pelotas , Brazil
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Effect of a short multicomponent exercise intervention focused on muscle power in frail and pre frail elderly: A pilot trial. Exp Gerontol 2018; 115:114-121. [PMID: 30528641 DOI: 10.1016/j.exger.2018.11.022] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 11/21/2018] [Accepted: 11/28/2018] [Indexed: 11/20/2022]
Abstract
OBJECTIVES The aim was to establish whether a short supervised facility-based exercise program improved frailty, physical function and performance in comparison with usual care treatment. METHODS This was a quasi-experimental, non-randomized controlled intervention study in frail (2.75 ± 1.25 Frailty Phenotype criteria) older adults (range:77.2-95.8 years). The exercise (EX) group (n = 11) performed concurrent training (power training + high-intensity interval training, HIIT) twice weekly for 6 weeks while the control (CT) group (n = 9) followed usual care. RESULTS The exercise intervention improved frailty status in 64% of the subjects improving Frailty Phenotype by 1.6 points (95%CI 0.8-2.5, p < 0.05), and increasing SPPB score by 3.2 points (95%CI: 2.4-4.0, Cohen's d = 2.0, p < 0.05), muscle power by 47% (95%CI: 7-87%, Cohen's d = 0.5, p < 0.05), muscle strength by 34%(95%CI: 7-60, Cohen's d = 0.6, p < 0.05) and the aerobic capacity by 19% (6 minute walking test +45 m, 95%CI: 7-83, Cohen's d = 0.7, p = 0.054). The CT did not experience any significant changes in frailty status, physical function or performance. CONCLUSIONS A short concurrent exercise program of muscle power and walking-based HIIT training is a feasible and safe method to increase physical performance and improve function and frailty in elder (pre)frail patients.
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Kyröläinen H, Pihlainen K, Vaara JP, Ojanen T, Santtila M. Optimising training adaptations and performance in military environment. J Sci Med Sport 2018; 21:1131-1138. [DOI: 10.1016/j.jsams.2017.11.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 11/15/2017] [Accepted: 11/28/2017] [Indexed: 11/28/2022]
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MARTINEZ-VALDES EDUARDO, FARINA DARIO, NEGRO FRANCESCO, DEL VECCHIO ALESSANDRO, FALLA DEBORAH. Early Motor Unit Conduction Velocity Changes to High-Intensity Interval Training versus Continuous Training. Med Sci Sports Exerc 2018; 50:2339-2350. [DOI: 10.1249/mss.0000000000001705] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Vastus lateralis muscle tissue composition and motor unit properties in chronically endurance-trained vs. sedentary women. Eur J Appl Physiol 2018; 118:1789-1800. [PMID: 29948198 DOI: 10.1007/s00421-018-3909-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Accepted: 05/30/2018] [Indexed: 10/14/2022]
Abstract
This study examined motor unit (MU) amplitudes (APAMPS) and firing rates during moderate-intensity contractions and muscle cross-sectional area (mCSA) and echo intensity (mEI) of the vastus lateralis (VL) in chronically endurance-trained and sedentary females. Eight endurance-trained (ET) and nine sedentary controls (SED) volunteered for this study. Surface electromyographic (EMG) signals from a five-pin electrode array were recorded from the VL during isometric trapezoid muscle actions at 40% of maximal voluntary contraction (MVC). Decomposition methods were applied to the EMG signals to extract the firing events and amplitudes of single MUs. The mean firing rate (MFR) during steady force and MUAPAMP for each MU was regressed against recruitment threshold (RT, expressed as %MVC). The y-intercepts and slopes from the MFR and MUAPAMP vs. RT relationships were calculated. EMG amplitude during steady force was normalized (N-EMGRMS) to peak EMG amplitude recorded during the MVC. Ultrasonography was used to measure mCSA and mEI. Significant differences existed between the ET and SED for the slopes (P = 0.005, P = 0.001) from the MFR and MUAPAMP vs. RT relationships with no differences for the y-intercepts (P > 0.05). N-EMGRMS was significantly (P = 0.033) lower for the ET than SED. There were no differences between groups for mCSA; however, the SED possessed significantly (P = 0.001) greater mEI. Subsequently, the ET likely possessed hypertrophied and stronger MUs that allowed for lower necessary muscle activation to maintain the same relative task as the SED. The larger MUs for the ET is supported via the MFR vs. RT relationships and ultrasound data.
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The effect of medication on vastus lateralis muscle activation patterns in Parkinson's disease patients. J Electromyogr Kinesiol 2018; 42:66-73. [PMID: 29960263 DOI: 10.1016/j.jelekin.2018.06.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 06/21/2018] [Accepted: 06/24/2018] [Indexed: 11/22/2022] Open
Abstract
The effect of levodopa on muscle activity patterns in Parkinson's disease (PD) patients is currently unclear. The aim of the present study was to compare the spatial distribution pattern of electromyographic activity during sustained isometric contraction in PD patients during on- and off-medication periods using multi-channel surface electromyography (SEMG). Ten female PD patients were recruited for the present study. All patients performed a sustained isometric knee extension at 10% maximum voluntary contraction task for 60 s. To evaluate alterations in the spatial SEMG potential distribution, the coefficient of variation (CV) of force, normalized root mean square (RMS), modified entropy, CV of the RMS, and correlation coefficients were calculated at during contraction task. The off-medication period exhibited more fluctuation during the contraction task than those in the on-medication period. The off-medication period exhibited less change in modified entropy, the CV of RMS, the correlation coefficient and patterns of spatial SEMG distribution. These data demonstrated that the heterogeneity and changes in the activation pattern are smaller in the off-medication period than in those in the on-medication period. These findings might indicate that levodopa enhanced the activation of muscle action potentials during force production.
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