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Coates AM, Joyner MJ, Little JP, Jones AM, Gibala MJ. A Perspective on High-Intensity Interval Training for Performance and Health. Sports Med 2023; 53:85-96. [PMID: 37804419 PMCID: PMC10721680 DOI: 10.1007/s40279-023-01938-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/12/2023] [Indexed: 10/09/2023]
Abstract
Interval training is a simple concept that refers to repeated bouts of relatively hard work interspersed with recovery periods of easier work or rest. The method has been used by high-level athletes for over a century to improve performance in endurance-type sports and events such as middle- and long-distance running. The concept of interval training to improve health, including in a rehabilitative context or when practiced by individuals who are relatively inactive or deconditioned, has also been advanced for decades. An important issue that affects the interpretation and application of interval training is the lack of standardized terminology. This particularly relates to the classification of intensity. There is no common definition of the term "high-intensity interval training" (HIIT) despite its widespread use. We contend that in a performance context, HIIT can be characterized as intermittent exercise bouts performed above the heavy-intensity domain. This categorization of HIIT is primarily encompassed by the severe-intensity domain. It is demarcated by indicators that principally include the critical power or critical speed, or other indices, including the second lactate threshold, maximal lactate steady state, or lactate turnpoint. In a health context, we contend that HIIT can be characterized as intermittent exercise bouts performed above moderate intensity. This categorization of HIIT is primarily encompassed by the classification of vigorous intensity. It is demarcated by various indicators related to perceived exertion, oxygen uptake, or heart rate as defined in authoritative public health and exercise prescription guidelines. A particularly intense variant of HIIT commonly termed "sprint interval training" can be distinguished as repeated bouts performed with near-maximal to "all out" effort. This characterization coincides with the highest intensity classification identified in training zone models or exercise prescription guidelines, including the extreme-intensity domain, anaerobic speed reserve, or near-maximal to maximal intensity classification. HIIT is considered an essential training component for the enhancement of athletic performance, but the optimal intensity distribution and specific HIIT prescription for endurance athletes is unclear. HIIT is also a viable method to improve cardiorespiratory fitness and other health-related indices in people who are insufficiently active, including those with cardiometabolic diseases. Research is needed to clarify responses to different HIIT strategies using robust study designs that employ best practices. We offer a perspective on the topic of HIIT for performance and health, including a conceptual framework that builds on the work of others and outlines how the method can be defined and operationalized within each context.
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Affiliation(s)
- Alexandra M Coates
- Department of Kinesiology, McMaster University, 1280 Main St West, Hamilton, ON, L8S 4K1, Canada
| | - Michael J Joyner
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - Jonathan P Little
- School of Health and Exercise Sciences, University of British Columbia, Kelowna, BC, Canada
| | - Andrew M Jones
- Sport and Health Sciences, University of Exeter, Exeter, UK
| | - Martin J Gibala
- Department of Kinesiology, McMaster University, 1280 Main St West, Hamilton, ON, L8S 4K1, Canada.
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2
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Matomäki P, Heinonen OJ, Nummela A, Laukkanen J, Auvinen EP, Pirkola L, Kyröläinen H. Durability is improved by both low and high intensity endurance training. Front Physiol 2023; 14:1128111. [PMID: 36875044 PMCID: PMC9977827 DOI: 10.3389/fphys.2023.1128111] [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: 12/20/2022] [Accepted: 01/31/2023] [Indexed: 02/18/2023] Open
Abstract
Introduction: This is one of the first intervention studies to examine how low- (LIT) and high-intensity endurance training (HIT) affect durability, defined as 'time of onset and magnitude of deterioration in physiological-profiling characteristics over time during prolonged exercise'. Methods: Sedentary and recreationally active men (n = 16) and women (n = 19) completed either LIT (average weekly training time 6.8 ± 0.7 h) or HIT (1.6 ± 0.2 h) cycling for 10 weeks. Durability was analyzed before and after the training period from three factors during 3-h cycling at 48% of pretraining maximal oxygen uptake (VO2max): 1) by the magnitude and 2) onset of drifts (i.e. gradual change in energy expenditure, heart rate, rate of perceived exertion, ventilation, left ventricular ejection time, and stroke volume), 3) by the 'physiological strain', defined to be the absolute responses of heart rate and its variability, lactate, and rate of perceived exertion. Results: When all three factors were averaged the durability was improved similarly (time x group p = 0.42) in both groups (LIT: p = 0.03, g = 0.49; HIT: p = 0.01, g = 0.62). In the LIT group, magnitude of average of drifts and their onset did not reach statistically significance level of p < 0.05 (magnitude: 7.7 ± 6.8% vs. 6.3 ± 6.0%, p = 0.09, g = 0.27; onset: 106 ± 57 min vs. 131 ± 59 min, p = 0.08, g = 0.58), while averaged physiological strain improved (p = 0.01, g = 0.60). In HIT, both magnitude and onset decreased (magnitude: 8.8 ± 7.9% vs. 5.4 ± 6.7%, p = 0.03, g = 0.49; onset: 108 ± 54 min vs. 137 ± 57 min, p = 0.03, g = 0.61), and physiological strain improved (p = 0.005, g = 0.78). VO2max increased only after HIT (time x group p < 0.001, g = 1.51). Conclusion: Durability improved similarly by both LIT and HIT based on reduced physiological drifts, their postponed onsets, and changes in physiological strain. Despite durability enhanced among untrained people, a 10-week intervention did not alter drifts and their onsets in a large amount, even though it attenuated physiological strain.
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Affiliation(s)
- Pekka Matomäki
- Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland.,Paavo Nurmi Centre & Unit for Health and Physical Activity, University of Turku, Turku, Finland
| | - Olli J Heinonen
- Paavo Nurmi Centre & Unit for Health and Physical Activity, University of Turku, Turku, Finland
| | - Ari Nummela
- Finnish Institute of High Performance Sport KIHU, Jyväskylä, Finland
| | - Jari Laukkanen
- Central Finland Healthcare District, Department of Medicine, Jyväskylä, Finland.,Department of Medicine, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
| | - Eero-Pekka Auvinen
- Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
| | - Leena Pirkola
- Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
| | - Heikki Kyröläinen
- Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
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Bioenergetic Evaluation of Muscle Fatigue in Murine Tongue. Dysphagia 2022:10.1007/s00455-022-10537-y. [DOI: 10.1007/s00455-022-10537-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 10/26/2022] [Indexed: 11/21/2022]
Abstract
AbstractMuscle fatigue is the diminution of force required for a particular action over time. Fatigue may be particularly pronounced in aging muscles, including those used for swallowing actions. Because risk for swallowing impairment (dysphagia) increases with aging, the contribution of muscle fatigue to age-related dysphagia is an emerging area of interest. The use of animal models, such as mice and rats (murine models) allows experimental paradigms for studying the relationship between muscle fatigue and swallowing function with a high degree of biological precision that is not possible in human studies. The goal of this article is to review basic experimental approaches to the study of murine tongue muscle fatigue related to dysphagia. Traditionally, murine muscle fatigue has been studied in limb muscles through direct muscle stimulation and behavioral exercise paradigms. As such, physiological and bioenergetic markers of muscle fatigue that have been validated in limb muscles may be applicable in studies of cranial muscle fatigue with appropriate modifications to account for differences in muscle architecture, innervation ratio, and skeletal support. Murine exercise paradigms may be used to elicit acute fatigue in tongue muscles, thereby enabling study of putative muscular adaptations. Using these approaches, hypotheses can be developed and tested in mice and rats to allow for future focused studies in human subjects geared toward developing and optimizing treatments for age-related dysphagia.
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Akhundov R, Saxby DJ, Diamond LE, Snodgrass S, Clausen P, Drew M, Dooley K, Pizzari T, Rio E, Schultz A, Donnan L, McGann T, Edwards S. Game-play affects hamstring but not adductor muscle fibre mechanics in elite U20 basketball athletes. Sports Biomech 2022:1-17. [PMID: 36254725 DOI: 10.1080/14763141.2022.2133006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 09/21/2022] [Indexed: 10/24/2022]
Abstract
Muscle tendon unit fibre mechanics of hamstring and adductor strain injuries are not well studied, with factors such as fatigue promoted as risk factors in the absence of mechanistic evidence. In this study, musculoskeletal modelling was used to estimate fibre mechanics of four hamstring (biceps femoris long head, biceps femoris short head, semimembranosus and semitendinosus) and four adductor (adductor brevis, adductor longus, adductor magnus and gracilis) muscles during an anticipated cut task. The cut task was performed by 10 healthy elite male U20 basketball players both before and immediately after they played in one (of four) competitive basketball game. Biceps femoris long head produced significantly lower (p = 0.032) submaximal force post-game in the latter part of swing (30.7% to 35.0% of stride), though its peak force occurred later (37%) and remained unchanged. Semimembranosus produced significantly lower (p = 0.006) force post-game (32.9% to 44.9% of stride), which encompassed the instance of peak force (39%). Neither fibre velocity nor fibre length of the investigated muscles were significantly affected by game-play. These finding suggest that if fatigue is a factor in hamstring and adductor muscle strain injuries and is brought about by game-play, it is unlikely through the fibre mechanisms investigated in this study.
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Affiliation(s)
- Riad Akhundov
- Griffith Centre for Biomedical and Rehabilitation Engineering (GCORE), Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
- School of Health Sciences and Social Work, Griffith University, Gold Coast, Queensland, Australia
- School of Health Sciences, The University of Newcastle, Callaghan, New South Wales, Australia
| | - David J Saxby
- Griffith Centre for Biomedical and Rehabilitation Engineering (GCORE), Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
| | - Laura E Diamond
- Griffith Centre for Biomedical and Rehabilitation Engineering (GCORE), Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
- School of Health Sciences and Social Work, Griffith University, Gold Coast, Queensland, Australia
| | - Suzanne Snodgrass
- School of Health Sciences, The University of Newcastle, Callaghan, New South Wales, Australia
| | - Phil Clausen
- School of Engineering, University of Newcastle, Callaghan, New South Wales, Australia
| | - Michael Drew
- Athlete Availability Program, Australian Institute of Sport, Bruce, Australian Capital Territory, Australia
- University of Canberra Research Institute for Sport and Exercise (UCRISE), University of Canberra, Bruce, Australian Capital Territory, Australia
- Australian Centre for Research into Injury in Sport and its Prevention, Bundoora, Victoria, Australia
| | - Katherine Dooley
- School of Health Sciences, The University of Newcastle, Callaghan, New South Wales, Australia
| | - Tania Pizzari
- La Trobe Sport and Exercise Medicine Research Centre, La Trobe University, Bundoora, Victoria, Australia
| | - Ebonie Rio
- La Trobe Sport and Exercise Medicine Research Centre, La Trobe University, Bundoora, Victoria, Australia
| | - Adrian Schultz
- School of Environment and Life Sciences, University of Newcastle, Callaghan, New South Wales, Australia
| | - Luke Donnan
- Faculty of Science, Charles Sturt University, Albury, New South Wales, Australia
| | - Tye McGann
- School of Health Sciences, The University of Newcastle, Callaghan, New South Wales, Australia
| | - Suzi Edwards
- School of Environment and Life Sciences, University of Newcastle, Callaghan, New South Wales, Australia
- Discipline of Exercise and Sport Science, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
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Balci GA, As H, Ozkaya O, Colakoglu M. Development potentials of commonly used high-intensity training strategies on central and peripheral components of maximal oxygen consumption. Respir Physiol Neurobiol 2022; 302:103910. [PMID: 35405332 DOI: 10.1016/j.resp.2022.103910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 03/16/2022] [Accepted: 04/06/2022] [Indexed: 10/18/2022]
Abstract
The aim of this study was to reveal the development potentials of five high-intensity training models on central and peripheral components of maximal oxygen consumption (VO2max). Following VO2max determination, maximal cardiac output (Qmax), maximal stroke volume (SVmax), and maximal arteriovenous O2 difference (a-vO2diff_max) were analysed. Short-interval- (short-HIIT), long-interval (long-HIIT), alternating work-rate continuous (alter-HIT), constant work-rate continuous (const-HIT), and sprint interval (SIT) sessions were performed on separate days with iso-effort and iso-time methods. Time spent (tspent) at > 95% of VO2max was the highest in long-HIIT (p < 0.05). The tspent at > 90% of Qmax was higher in alter-HIT than long-HIIT and SIT (p < 0.05), while there was no significant difference for tspent at > 90% of SVmax amongst high-intensity trainings. The tspent at > 90% of a-vO2diff_max was higher in short-HIIT and long-HIIT than other modalities (p < 0.05). It can be said that continuous modalities seem to have a higher potential to improve central part of VO2max, while interval modalities may be better to develop peripheral component.
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Affiliation(s)
- Gorkem Aybars Balci
- Department of Coaching Education, Faculty of Sports Sciences, Ege University, Turkey
| | - Hakan As
- Department of Sports Health Sciences, Institution of Health Sciences, Ege University, Turkey
| | - Ozgur Ozkaya
- Department of Coaching Education, Faculty of Sports Sciences, Ege University, Turkey
| | - Muzaffer Colakoglu
- Department of Coaching Education, Faculty of Sports Sciences, Ege University, Turkey.
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Briand J, Tremblay J, Thibault G. Can Popular High-Intensity Interval Training (HIIT) Models Lead to Impossible Training Sessions? Sports (Basel) 2022; 10:sports10010010. [PMID: 35050975 PMCID: PMC8822890 DOI: 10.3390/sports10010010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 12/28/2021] [Accepted: 12/30/2021] [Indexed: 01/25/2023] Open
Abstract
High-Intensity Interval Training (HIIT) is a time-efficient training method suggested to improve health and fitness for the clinical population, healthy subjects, and athletes. Many parameters can impact the difficulty of HIIT sessions. This study aims to highlight and explain, through logical deductions, some limitations of the Skiba and Coggan models, widely used to prescribe HIIT sessions in cycling. We simulated 6198 different HIIT training sessions leading to exhaustion, according to the Skiba and Coggan-Modified (modification of the Coggan model with the introduction of an exhaustion criterion) models, for three fictitious athlete profiles (Time-Trialist, All-Rounder, Sprinter). The simulation revealed impossible sessions (i.e., requiring athletes to surpass their maximal power output over the exercise interval duration), characterized by a few short exercise intervals, performed in the severe and extreme intensity domains, alternating with long recovery bouts. The fraction of impossible sessions depends on the athlete profile and ranges between 4.4 and 22.9% for the Skiba model and 0.6 and 3.2% for the Coggan-Modified model. For practitioners using these HIIT models, this study highlights the importance of understanding these models’ inherent limitations and mathematical assumptions to draw adequate conclusions from their use to prescribe HIIT sessions.
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Affiliation(s)
- Jérémy Briand
- Institut National du Sport du Québec, 4141 Avenue Pierre-De-Coubertin, Montreal, QC H1V 3N7, Canada; (J.B.); (G.T.)
- École de Kinésiologie et des Sciences de l’Activité Physique, Faculté de Médecine, Université de Montréal, 2100 Boulevard Édouard-Montpetit, Montreal, QC H3T 1J4, Canada
| | - Jonathan Tremblay
- École de Kinésiologie et des Sciences de l’Activité Physique, Faculté de Médecine, Université de Montréal, 2100 Boulevard Édouard-Montpetit, Montreal, QC H3T 1J4, Canada
- Correspondence:
| | - Guy Thibault
- Institut National du Sport du Québec, 4141 Avenue Pierre-De-Coubertin, Montreal, QC H1V 3N7, Canada; (J.B.); (G.T.)
- École de Kinésiologie et des Sciences de l’Activité Physique, Faculté de Médecine, Université de Montréal, 2100 Boulevard Édouard-Montpetit, Montreal, QC H3T 1J4, Canada
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Bouffard S, Paradis-Deschênes P, Billaut F. Neuromuscular Adjustments Following Sprint Training with Ischemic Preconditioning in Endurance Athletes: Preliminary Data. Sports (Basel) 2021; 9:sports9090124. [PMID: 34564329 PMCID: PMC8470678 DOI: 10.3390/sports9090124] [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: 07/23/2021] [Revised: 08/17/2021] [Accepted: 08/30/2021] [Indexed: 11/16/2022] Open
Abstract
This preliminary study examined the effect of chronic ischemic preconditioning (IPC) on neuromuscular responses to high-intensity exercise. In a parallel-group design, twelve endurance-trained males (VO2max 60.0 ± 9.1 mL·kg−1·min−1) performed a 30-s Wingate test before, during, and after 4 weeks of sprint-interval training. Training consisted of bi-weekly sessions of 4 to 7 supra-maximal all-out 30-s cycling bouts with 4.5 min of recovery, preceded by either IPC (3 × 5-min of compression at 220 mmHg/5-min reperfusion, IPC, n = 6) or placebo compressions (20 mmHg, PLA, n = 6). Mechanical indices and the root mean square and mean power frequency of the electromyographic signal from three lower-limb muscles were continuously measured during the Wingate tests. Data were averaged over six 5-s intervals and analyzed with Cohen’s effect sizes. Changes in peak power output were not different between groups. However, from mid- to post-training, IPC improved power output more than PLA in the 20 to 25-s interval (7.6 ± 10.0%, ES 0.51) and the 25 to 30-s interval (8.8 ± 11.2%, ES 0.58), as well as the fatigue index (10.0 ± 2.3%, ES 0.46). Concomitantly to this performance difference, IPC attenuated the decline in frequency spectrum throughout the Wingate (mean difference: 14.8%, ES range: 0.88–1.80). There was no difference in root mean square amplitude between groups. These preliminary results suggest that using IPC before sprint training may enhance performance during a 30-s Wingate test, and such gains occurred in the last 2 weeks of the intervention. This improvement may be due, in part, to neuromuscular adjustments induced by the chronic use of IPC.
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Affiliation(s)
- Stéphan Bouffard
- Department of Kinesiology, Laval University, Quebec, QC G1V 0A6, Canada; (S.B.); (P.P.-D.)
| | | | - François Billaut
- Department of Kinesiology, Laval University, Quebec, QC G1V 0A6, Canada; (S.B.); (P.P.-D.)
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, QC G1V 4G5, Canada
- Correspondence:
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The Association Between the Acute:Chronic Workload Ratio and Running-Related Injuries in Dutch Runners: A Prospective Cohort Study. Sports Med 2021; 51:2437-2447. [PMID: 34052983 DOI: 10.1007/s40279-021-01483-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/03/2021] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To investigate the association between the acute:chronic workload ratio (ACWR) and running-related injuries (RRI). METHODS This is a secondary analysis using a database composed of data from three studies conducted with the same RRI surveillance system. Longitudinal data comprising running exposure (workload) and RRI were collected biweekly during the respective cohorts' follow-up (18-65 weeks). ACWR was calculated as the most recent (i.e., acute) external workload (last 2 weeks) divided by the average external (i.e., chronic) workload of the last 4, 6, 8, 10 and 12 weeks. Three methods were used to calculate the ACWR: uncoupled, coupled and exponentially weighted moving averages (EWMA). Bayesian logistic mixed models were used to analyse the data. RESULTS The sample was composed of 435 runners. Runners whose ACWR was under 0.70 had about 10% predicted probability of sustaining RRI (9.6%; 95% credible interval [CrI] 7.5-12.4), while those whose ACWR was higher than 1.38 had about 1% predicted probability of sustaining RRI (1.3%; 95% CrI 0.7-1.7). The association between the ACWR and RRI was significant, varying from a small to a moderate association (1-10%). The higher the ACWR, the lower the RRI risk. CONCLUSIONS The ACWR showed an inversely proportional association with RRI risk that can be represented by a smooth L-shaped, second-order, polynomial decay curve. The ACWR using hours or kilometres yielded similar results. The coupled and uncoupled methods revealed similar associations with RRIs. The uncoupled method presented the best discrimination for ACWR strata. The EWMA method yielded sparse and non-significant results.
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García-De Frutos JM, Orquín-Castrillón FJ, Marcos-Pardo PJ, Rubio-Arias JÁ, Martínez-Rodríguez A. Acute Effects of Work Rest Interval Duration of 3 HIIT Protocols on Cycling Power in Trained Young Adults. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18084225. [PMID: 33923545 PMCID: PMC8073758 DOI: 10.3390/ijerph18084225] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 04/10/2021] [Accepted: 04/13/2021] [Indexed: 01/09/2023]
Abstract
High-Intensity Interval Training (HIIT) is described as a succession of short duration and maximum or near-maximum intensity efforts, alternated by recovery periods during which exercise continues at a lower intensity (active recovery) or is interrupted (passive recovery). Our objective was to evaluate the acute responses of three HIIT protocols of different work/rest interval times over the total time of the session, with self-selectable load and up to exhaustion, “all out”.The sample was composed of 22 male participants (n = 22) between 19 and 24 years old. The HIIT protocol consisted of one of the three HIIT protocols, of 30, 60 and 90 s density ratio 1:1 and with passive rest, with a total exercise duration of 10 min. The test was performed in a cycloergometer set in workload mode independent of the pedaling frequency. The comparison of the three HIIT protocols shows that the duration of the work/rest intervals, starting from 30 s of work, in the cycloergometer, there are no significant differences in the levels of lactate concentration in the blood, nor in the heart rate, since a similar amount is obtained in the three protocols. The percentage of maximum power developed reached in each HIIT protocol is related to the duration of the working intervals.
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Affiliation(s)
- José Manuel García-De Frutos
- Physical Activity and Sport Sciences Department, Faculty of Sport, Catholic University San Antonio of Murcia, 30107 Murcia, Spain; (J.M.G.-D.F.); (F.J.O.-C.)
| | - Fco. Javier Orquín-Castrillón
- Physical Activity and Sport Sciences Department, Faculty of Sport, Catholic University San Antonio of Murcia, 30107 Murcia, Spain; (J.M.G.-D.F.); (F.J.O.-C.)
| | - Pablo Jorge Marcos-Pardo
- Department of Education, Faculty of Education Sciences, University of Almería, 04120 Almería, Spain; (P.J.M.-P.); (J.Á.R.-A.)
- SPORT Research Group (CTS-1024), CERNEP Research Center, University of Almería, 04120 Almería, Spain
| | - Jacobo Á. Rubio-Arias
- Department of Education, Faculty of Education Sciences, University of Almería, 04120 Almería, Spain; (P.J.M.-P.); (J.Á.R.-A.)
| | - Alejandro Martínez-Rodríguez
- Department of Analytical Chemistry, Nutrition and Food Sciences, Faculty of Science, Universidad de Alicante, 03690 Alicante, Spain
- Alicante Institute for Health and Biomedical Research (ISABIAL Foundation), 03010 Alicante, Spain
- Correspondence:
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10
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Bellinger P. Functional Overreaching in Endurance Athletes: A Necessity or Cause for Concern? Sports Med 2021; 50:1059-1073. [PMID: 32064575 DOI: 10.1007/s40279-020-01269-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
There are variable responses to short-term periods of increased training load in endurance athletes, whereby some athletes improve without deleterious effects on performance, while others show diminished exercise performance for a period of days to months. The time course of the decrement in performance and subsequent restoration, or super compensation, has been used to distinguish between the different stages of the fitness-fatigue adaptive continuum termed functional overreaching (FOR), non-functional overreaching (NFOR) or overtraining syndrome. The short-term transient training-induced decrements in performance elicited by increases in training load (i.e. FOR) are thought be a sufficient and necessary component of a training program and are often deliberately induced in training to promote meaningful physiological adaptations and performance super-compensation. Despite the supposition that deliberately inducing FOR in athletes may be necessary to achieve performance super-compensation, FOR has been associated with various negative cardiovascular, hormonal and metabolic consequences. Furthermore, recent studies have demonstrated dampened training and performance adaptations in FOR athletes compared to non-overreached athletes who completed the same training program or the same relative increase in training load. However, this is not always the case and a number of studies have also demonstrated substantial performance super-compensation in athletes who were classified as being FOR. It is possible that there are a number of contextual factors that may influence the metabolic consequences associated with FOR and classifying this training-induced state of fatigue based purely on a decrement in performance may be an oversimplification. Here, the most recent research on FOR in endurance athletes will be critically evaluated to determine (1) if there is sufficient evidence to indicate that inducing a state of FOR is necessary and required to induce a performance super-compensation; (2) the metabolic consequences that are associated with FOR; (3) strategies that may prevent the negative consequences of overreaching.
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Affiliation(s)
- Phillip Bellinger
- Griffith Sports Physiology and Performance, Griffith University, Gold Coast, QLD, Australia. .,Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia.
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Parmar A, Jones TW, Hayes PR. The dose-response relationship between interval-training and VO 2max in well-trained endurance runners: A systematic review. J Sports Sci 2021; 39:1410-1427. [PMID: 33605843 DOI: 10.1080/02640414.2021.1876313] [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] [Indexed: 01/23/2023]
Abstract
Success in endurance running is primarily determined by maximal aerobic power (VO2max), fractional utilization, and running economy (RE). Within the literature, two training modalities have been identified to improve VO2max; continuous training (CT) and interval-training (IT). The efficacy of IT to improve VO2max in well-trained runners remains equivocal, as does whether a dose-response relationship exists between the IT training load performed and changes in VO2max. A keyword search was performed in five electronic databases. Seven studies met the inclusion criteria for this systematic review. The training impulse (TRIMP) was calculated to analyse relationships between training load and changes in VO2max, by calculating the time accumulated in certain intensity domains throughout a training intervention. Non-significant (P>0.05) improvements in VO2max were reported in six studies, with only one study reporting a significant (P<0.05) improvement following the IT interventions. A relationship between the training session impulse of the interval-training performed (IT STRIMP) and VO2max improvements were observed. The efficacy of IT to improve VO2max in well-trained runners remains equivocal, nevertheless, the novel method of training-load analysis demonstrates a relationship between the IT STRIMP and VO2max improvements. This provides practical application for the periodization of IT within the training regime of well-trained distance runners.
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Affiliation(s)
- Arran Parmar
- Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Thomas W Jones
- Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
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Kubová S, Pavlů D, Pánek D, Hojka V, Jebavý R, Kuba K. The effect of short-term strength intervention on muscle activity of shoulder girdle during simulated crawl in elite swimmers. ACTA GYMNICA 2021. [DOI: 10.5507/ag.2020.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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13
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Abstract
Ultra Short Race Pace training (USRPT) is an emerging training modality devised in 2011 to deviate from high-volume swimming training that is typically prescribed. USRPT aims to replicate the exact demands of racing, through its unique prescription of race-pace velocity sets with short rest intervals. It has been surmised, with little physiological evidence, that USRPT provides swimmers with the best opportunity to optimize the conditioning, technique, and psychology aspects of racing at the most specific velocity of the relevant event, with low blood lactate concentration. The aim of this study was to examine acute physiological responses of USRPT. Fourteen swimmers were recruited to perform a USRPT set: 20 x 25 m freestyle with a 35-s rest interval. Swimmers were required to maintain the velocity of their 100 m personal best time for each sprint. Sprint performance, blood lactate, heart rate and the RPE were measured. Blood lactate was taken before, during (after every 4 sprints) and 3 minutes after the USRPT protocol. Heart rate monitors were used to profile the heart rate. Athletes reported the RPE before- and after completion of the USRPT set. Sprint times increased by 3.3-10.8% when compared to the first sprint (p < 0.01). There was high blood lactate concentration (13.6 ± 3.1mmol/l), a significant change in the RPE from 8 ± 1.6 to 18 ± 1.6 (p < 0.01) and a substantially high heart rate profile with an average HRmax of 188 ± 9 BPM. The results show the maximal intensity nature of USRPT and portray it as an anaerobic style of training.
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Fennell CRJ, Hopker JG. The acute physiological and perceptual effects of recovery interval intensity during cycling-based high-intensity interval training. Eur J Appl Physiol 2020; 121:425-434. [PMID: 33098020 PMCID: PMC7862540 DOI: 10.1007/s00421-020-04535-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 10/13/2020] [Indexed: 11/24/2022]
Abstract
Purpose The current study sought to investigate the role of recovery intensity on the physiological and perceptual responses during cycling-based aerobic high-intensity interval training. Methods Fourteen well-trained cyclists (\documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{{{\text{2peak}}}}$$\end{document}V˙O2peak: 62 ± 9 mL kg−1 min−1) completed seven laboratory visits. At visit 1, the participants’ peak oxygen consumption (\documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{{{\text{2peak}}}}$$\end{document}V˙O2peak) and lactate thresholds were determined. At visits 2–7, participants completed either a 6 × 4 min or 3 × 8 min high-intensity interval training (HIIT) protocol with one of three recovery intensity prescriptions: passive (PA) recovery, active recovery at 80% of lactate threshold (80A) or active recovery at 110% of lactate threshold (110A). Results The time spent at > 80%, > 90% and > 95% of maximal minute power during the work intervals was significantly increased with PA recovery, when compared to both 80A and 110A, during both HIIT protocols (all P ≤ 0.001). However, recovery intensity had no effect on the time spent at > 90% \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{{{\text{2peak}}}}$$\end{document}V˙O2peak (P = 0.11) or > 95% \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{{{\text{2peak}}}}$$\end{document}V˙O2peak (P = 0.50) during the work intervals of both HIIT protocols. Session RPE was significantly higher following the 110A recovery, when compared to the PA and 80A recovery during both HIIT protocols (P < 0.001). Conclusion Passive recovery facilitates a higher work interval PO and similar internal stress for a lower sRPE when compared to active recovery and therefore may be the efficacious recovery intensity prescription.
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Affiliation(s)
- Christopher R J Fennell
- School of Sport and Exercise Sciences, University of Kent at Medway, Medway Building, Kent, Chatham, ME4 4AG, England, UK
| | - James G Hopker
- School of Sport and Exercise Sciences, University of Kent at Medway, Medway Building, Kent, Chatham, ME4 4AG, England, UK.
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Almquist NW, Nygaard H, Vegge G, Hammarström D, Ellefsen S, Rønnestad BR. Systemic and muscular responses to effort-matched short intervals and long intervals in elite cyclists. Scand J Med Sci Sports 2020; 30:1140-1150. [PMID: 32267032 DOI: 10.1111/sms.13672] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 03/25/2020] [Accepted: 03/25/2020] [Indexed: 01/01/2023]
Abstract
The purpose of this study was to compare the acute effects of time- and effort-matched high-intensity intervals on physiological, endocrine, and skeletal muscle molecular variables in elite cyclists. Eight elite cyclists performed short intervals (SI: 30-seconds) and long intervals (LI: 5-minutes) with work:recovery ratio 2:1, using a randomized crossover design. SI was associated with 14% ± 3% higher mean power output (SI; 421 ± 27 vs LI; 371 ± 22 W), and longer working time above 90% of maximal oxygen uptake (VO2max , 54% ± 76%) and 90% peak heart rate (HRpeak , 153% ± 148%) than LI (all P < .05), despite similar degrees of perceived exertion, blood lactate levels and muscle activation measured using EMG root mean square (EMG rms). In blood, SI was associated with more pronounced increases in testosterone and testosterone-to-sex hormone-binding globulin (SHBG) ratios, as well as prolonged cortisol responses (P < .05). In skeletal muscle (m. Vastus lateralis), SI and LI led to similar changes in mRNA abundance for a range of transcripts, with the exception of NHE1 mRNA, which decreased after SI (P < .05). Overall, SI was associated with more pronounced physiological and endocrine responses than LI in elite cyclists, suggesting that such training might lead to superior adaptations in elite cyclists.
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Affiliation(s)
- Nicki W Almquist
- Section for Health and Exercise Physiology, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Håvard Nygaard
- Section for Health and Exercise Physiology, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Geir Vegge
- Section for Health and Exercise Physiology, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Daniel Hammarström
- Section for Health and Exercise Physiology, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Stian Ellefsen
- Section for Health and Exercise Physiology, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Bent R Rønnestad
- Section for Health and Exercise Physiology, Inland Norway University of Applied Sciences, Lillehammer, Norway
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Paradis-Deschênes P, Joanisse DR, Mauriège P, Billaut F. Ischemic Preconditioning Enhances Aerobic Adaptations to Sprint-Interval Training in Athletes Without Altering Systemic Hypoxic Signaling and Immune Function. Front Sports Act Living 2020; 2:41. [PMID: 33345033 PMCID: PMC7739728 DOI: 10.3389/fspor.2020.00041] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 03/25/2020] [Indexed: 01/29/2023] Open
Abstract
Optimizing traditional training methods to elicit greater adaptations is paramount for athletes. Ischemic preconditioning (IPC) can improve maximal exercise capacity and up-regulate signaling pathways involved in physiological training adaptations. However, data on the chronic use of IPC are scarce and its impact on high-intensity training is still unknown. We investigated the benefits of adding IPC to sprint-interval training (SIT) on performance and physiological adaptations of endurance athletes. In a randomized controlled trial, athletes included eight SIT sessions in their training routine for 4 weeks, preceded by IPC (3 × 5 min ischemia/5 min reperfusion cycles at 220 mmHg, n = 11) or a placebo (20 mmHg, n = 9). Athletes were tested pre-, mid-, and post-training on a 30 s Wingate test, 5-km time trial (TT), and maximal incremental step test. Arterial O2 saturation, heart rate, rate of perceived exertion, and quadriceps muscle oxygenation changes in total hemoglobin (Δ[THb]), deoxyhemoglobin (Δ[HHb]), and tissue saturation index (ΔTSI) were measured during exercise. Blood samples were taken pre- and post-training to determine blood markers of hypoxic response, lipid-lipoprotein profile, and immune function. Differences within and between groups were analyzed using Cohen's effect size (ES). Compared to PLA, IPC improved time to complete the TT (Mid vs. Post: -1.6%, Cohen's ES ± 90% confidence limits -0.24, -0.40;-0.07) and increased power output (Mid vs. Post: 4.0%, ES 0.20, 0.06;0.35), Δ[THb] (Mid vs. Post: 73.6%, ES 0.70, -0.15;1.54, Pre vs. Post: 68.5%, ES 0.69, -0.05;1.43), Δ[HHb] (Pre vs. Post: 12.7%, ES 0.24, -0.11;0.59) and heart rate (Pre vs. Post: 1.4%, ES 0.21, -0.13;0.55, Mid vs. Post: 1.6%, ES 0.25, -0.09;0.60). IPC also attenuated the fatigue index in the Wingate test (Mid vs. Post: -8.4%, ES -0.37, -0.79;0.05). VO2peak and maximal aerobic power remained unchanged in both groups. Changes in blood markers of the hypoxic response, vasodilation, and angiogenesis remained within the normal clinical range in both groups. We concluded that IPC combined with SIT induces greater adaptations in cycling endurance performance that may be related to muscle perfusion and metabolic changes. The absence of elevated markers of immune function suggests that chronic IPC is devoid of deleterious effects in athletes, and is thus a safe and potent ergogenic tool.
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Affiliation(s)
- Pénélope Paradis-Deschênes
- Département de kinésiologie, Université Laval, Québec, QC, Canada
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, QC, Canada
| | - Denis R. Joanisse
- Département de kinésiologie, Université Laval, Québec, QC, Canada
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, QC, Canada
| | - Pascale Mauriège
- Département de kinésiologie, Université Laval, Québec, QC, Canada
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, QC, Canada
| | - François Billaut
- Département de kinésiologie, Université Laval, Québec, QC, Canada
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, QC, Canada
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17
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Kistner S, Rist MJ, Krüger R, Döring M, Schlechtweg S, Bub A. High-Intensity Interval Training Decreases Resting Urinary Hypoxanthine Concentration in Young Active Men-A Metabolomic Approach. Metabolites 2019; 9:metabo9070137. [PMID: 31295919 PMCID: PMC6680906 DOI: 10.3390/metabo9070137] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 06/28/2019] [Accepted: 07/07/2019] [Indexed: 12/14/2022] Open
Abstract
High-intensity interval training (HIIT) is known to improve performance and skeletal muscle energy metabolism. However, whether the body’s adaptation to an exhausting short-term HIIT is reflected in the resting human metabolome has not been examined so far. Therefore, a randomized controlled intervention study was performed to investigate the effect of a ten-day HIIT on the resting urinary metabolome of young active men. Fasting spot urine was collected before (−1 day) and after (+1 day; +4 days) the training intervention and 65 urinary metabolites were identified by liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR) spectroscopy. Metabolite concentrations were normalized to urinary creatinine and subjected to univariate statistical analysis. One day after HIIT, no overall change in resting urinary metabolome, except a significant difference with decreasing means in urinary hypoxanthine concentration, was documented in the experimental group. As hypoxanthine is related to purine degradation, lower resting urinary hypoxanthine levels may indicate a training-induced adaptation in purine nucleotide metabolism.
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Affiliation(s)
- Sina Kistner
- Institute of Sports and Sports Science, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany.
| | - Manuela J Rist
- Department of Physiology and Biochemistry of Nutrition, Max Rubner-Institut, 76131 Karlsruhe, Germany
| | - Ralf Krüger
- Department of Physiology and Biochemistry of Nutrition, Max Rubner-Institut, 76131 Karlsruhe, Germany
| | - Maik Döring
- Department of Physiology and Biochemistry of Nutrition, Max Rubner-Institut, 76131 Karlsruhe, Germany
| | - Sascha Schlechtweg
- Department of Sport and Exercise Science, University of Stuttgart, 70174 Stuttgart, Germany
| | - Achim Bub
- Institute of Sports and Sports Science, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
- Department of Physiology and Biochemistry of Nutrition, Max Rubner-Institut, 76131 Karlsruhe, Germany
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Coates AM, Millar PJ, Burr JF. Blunted Cardiac Output from Overtraining Is Related to Increased Arterial Stiffness. Med Sci Sports Exerc 2019; 50:2459-2464. [PMID: 30102678 DOI: 10.1249/mss.0000000000001725] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE Moderate overtraining has been characterized by decreased exercising HR and recently decreased exercising stroke volume (SV), independent of alterations to blood volume. The aim of this study was to assess changes in arterial stiffness and central hemodynamics, and their relationship to exercising SV, after 3 wk of overload training. METHODS Twenty-six cyclists and triathletes completed 3 wk of either regular training (CON; n = 13) or overload training (OL; n = 13). Testing took place before (PRE) and after regular or overload training (POST). Resting measures included brachial blood pressure, HR, carotid-femoral pulse wave velocity (PWV) to assess arterial stiffness, and carotid pulse wave analysis to assess wave reflections and central hemodynamics. An incremental cycle test was used to assess peak power, maximal HR, and maximal lactate to assess overtraining status. Cardiac output (Q˙), SV, and HR were assessed using cardiac impedance. RESULTS Resting arterial stiffness was unaltered in CON but increased with OL after increased training (CON -0.1 ± 0.6 m·s vs OL +0.5 ± 0.8 m·s, P = 0.04). Resting blood pressure and central hemodynamics, including aortic pressures, augmentation index, and subendocardial viability ratio, did not change (all P > 0.05). Maximal SV (CON +3 mL vs OL -9 mL, P = 0.04), HR (CON -2 ± 4 bpm vs OL -9 ± 3 bpm, P < 0.001), and Q˙ (CON +0.32 L·min vs OL -1.75 L·min, P = 0.01) decreased with OL from PRE to POST. A significant inverse relationship existed between changes in PWV and maximal Q˙ (r = -0.44, P = 0.04) and changes in PWV and peak power (r = -0.48, P = 0.01), and trended for SV and PWV (r = -0.41, P = 0.055). CONCLUSIONS Overload training results in increased resting arterial stiffness and reduced SV during exercise, with no changes to resting central hemodynamics.
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Affiliation(s)
- Alexandra M Coates
- The Human Performance and Health Research Laboratory, Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, CANADA
| | - Philip J Millar
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, CANADA.,Toronto General Research Institute, Toronto General Hospital, Toronto, ON, CANADA
| | - Jamie F Burr
- The Human Performance and Health Research Laboratory, Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, CANADA
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Electromyography-signal-based muscle fatigue assessment for knee rehabilitation monitoring systems. Biomed Eng Lett 2019; 8:345-353. [PMID: 30603219 DOI: 10.1007/s13534-018-0078-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 06/23/2018] [Accepted: 06/27/2018] [Indexed: 10/28/2022] Open
Abstract
This study suggested a new EMG-signal-based evaluation method for knee rehabilitation that provides not only fragmentary information like muscle power but also in-depth information like muscle fatigue in the field of rehabilitation which it has not been applied to. In our experiment, nine healthy subjects performed straight leg raise exercises which are widely performed for knee rehabilitation. During the exercises, we recorded the joint angle of the leg and EMG signals from four prime movers of the leg: rectus femoris (RFM), vastus lateralis, vastus medialis, and biceps femoris (BFLH). We extracted two parameters to estimate muscle fatigue from the EMG signals, the zero-crossing rate (ZCR) and amplitude of muscle tension (AMT) that can quantitatively assess muscle fatigue from EMG signals. We found a decrease in the ZCR for the RFM and the BFLH in the muscle fatigue condition for most of the subjects. Also, we found increases in the AMT for the RFM and the BFLH. Based on the results, we quantitatively confirmed that in the state of muscle fatigue, the ZCR shows a decreasing trend whereas the AMT shows an increasing trend. Our results show that both the ZCR and AMT are useful parameters for characterizing the EMG signals in the muscle fatigue condition. In addition, our proposed methods are expected to be useful for developing a navigation system for knee rehabilitation exercises by evaluating the two parameters in two-dimensional parameter space.
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Heikura IA, Stellingwerff T, Burke LM. Self-Reported Periodization of Nutrition in Elite Female and Male Runners and Race Walkers. Front Physiol 2018; 9:1732. [PMID: 30559680 PMCID: PMC6286987 DOI: 10.3389/fphys.2018.01732] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 11/16/2018] [Indexed: 12/29/2022] Open
Abstract
Athletes should achieve event-specific physiological requirements through careful periodization of training, underpinned by individualized and targeted nutrition strategies. However, evidence of whether, and how, elite endurance athletes periodize nutrition is scarce. Accordingly, elite international female (n = 67) and male (n = 37) middle/long-distance athletes (IAAF score: 1129 ± 54, corresponds to 13:22.49 [males] and 15:17.93 [females] in the 5000 m) completed an online survey (February-May 2018) examining self-reported practices of dietary periodization for micro (within/between-days), meso (weeks/months) and macro (across the year) contexts. Data are shown as the percentage of all athletes practicing a given strategy followed by the % of athletes reporting various beliefs or practices within this strategy. Differences according to sex, event (middle-distance [800 m/1500 m] vs. track-distance [3000 m-10000 m] vs. road-distance [marathon/race walks]), caliber (high [major championship qualifier] vs. lower), and training volume (low/moderate/high male and female tertiles) were analyzed using Chi-square test or Kruskal-Wallis Test and indicated statistically different when p ≤ 0.05. Most athletes reported eating more on hard training days (92%) and focusing on nutrition before (84%; carbohydrate intake [63%] and timing [58%]) and after (95%; protein goals [59%], timing [55%], carbohydrate goals [50%]) key sessions. Road-distance were the most (62 and 57%), and middle-distance the least (30 and 30%) likely to train fasted (p = 0.037) or restrict carbohydrates periodically (p = 0.050), respectively. Carbohydrate intake during training (58% of total) was more common in males (79%; p = 0.004) and road-distance (90%; p < 0.001) than females (53%) or middle/track-distance (48 and 37%). Most athletes (83%) reported following a specific diet before and during race day, with half of the athletes focusing on carbohydrates. Nearly all (97%) road-distance athletes reported following a during-race nutrition plan (carbohydrates/fluids:89%). Only 32% reported taking advice from a dietitian/nutritionist. Based on our analysis: (1) Road-distance athletes periodize carbohydrate availability while track/middle-distance avoid low carbohydrate availability; (2) Middle-distance runners emphasize physique goals to guide their nutrition strategies; (3) Females seem to be more cautious of increasing energy/carbohydrate intake; (4) Among all athletes, nutrition strategies are chosen primarily to improve performance, followed by reasons related to physique, adaptation and health outcomes. Overall, these athletes appear to possess good knowledge of nutrition for supporting training and competition performance.
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Affiliation(s)
- Ida Aliisa Heikura
- Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, VIC, Australia
- Sports Nutrition, Australian Institute of Sport, Canberra, ACT, Australia
| | | | - Louise Mary Burke
- Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, VIC, Australia
- Sports Nutrition, Australian Institute of Sport, Canberra, ACT, Australia
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Enette L, Vogel T, Fanon JL, Lang PO. Effect of Interval and Continuous Aerobic Training on Basal Serum and Plasma Brain-Derived Neurotrophic Factor Values in Seniors: A Systematic Review of Intervention Studies. Rejuvenation Res 2017; 20:473-483. [DOI: 10.1089/rej.2016.1886] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Affiliation(s)
- Lievyn Enette
- Doctoral School in Life and Health Sciences, European Doctoral College (CDE), Strasbourg, France
- Department of Physiology and EA-3072, Medicine School, Strasbourg University, Strasbourg, France
| | - Thomas Vogel
- Department of Physiology and EA-3072, Medicine School, Strasbourg University, Strasbourg, France
- Geriatric Department, University Hospital, Strasbourg, France
| | - Jean Luc Fanon
- Department of Geriatric and Gerontology, University Hospital Centre of Martinique, Fort de France, France
| | - Pierre Olivier Lang
- Health and Wellbeing Academy, Anglia Ruskin University, Cambridge, United Kingdom
- Division of Geriatrics and Geriatric Rehabilitation, University Hospital of Lausanne (CHUV), Lausanne, Switzerland
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Allison MK, Baglole JH, Martin BJ, Macinnis MJ, Gurd BJ, Gibala MJ. Brief Intense Stair Climbing Improves Cardiorespiratory Fitness. Med Sci Sports Exerc 2017; 49:298-307. [PMID: 28009784 DOI: 10.1249/mss.0000000000001188] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
PURPOSE Sprint interval training (SIT) is a time-efficient strategy to improve cardiorespiratory fitness (CRF); however, most protocols have been studied in laboratory settings and require specialized equipment. We investigated the efficacy of brief intense stair climbing as a practical model of SIT to improve CRF. METHODS Two separate studies, each consisting of an acute and chronic phase, were conducted in a total of 31 sedentary women (age = 24 ± 10 yr, body mass index = 23 ± 4 kg·m). RESULTS The acute phase of study 1 established that the mean HR, blood [lactate], and RPE were similar when participants (n = 8) performed an SIT protocol that involved 3 × 20-s "all-out" efforts of either continuously ascending stairs or cycling. The chronic phase demonstrated that CRF, as determined by peak oxygen uptake (V˙O2peak), increased by 12% or ~1 MET (8.27 ± 1.05 to 9.25 ± 1.01 METs, P = 0.002) when participants (n = 12) performed the 3 × 20-s stair climbing protocol 3 d·wk for 6 wk. The acute phase of study 2 established that HR and RPE were similar when participants (n = 11) performed three different stair climbing protocols: the 3 × 20-s continuous ascent model used in study 1 and two 3 × 60-s models of ascending and descending either one or two flights of stairs (P > 0.05). The chronic phase demonstrated that V˙O2peak increased by 7% (8.91 ± 1.30 to 9.51 ± 1.52 METs, P = 0.01) when the same group of participants performed the one-flight 3 × 60-s protocol 3 d·wk for 6 wk. The Cederholm index determined from an oral glucose tolerance test was 57 ± 17 and 64 ± 21 mg·L·mmol·mU·min before and after training, respectively (P = 0.056). CONCLUSION Brief, intense stair climbing is a practical, time-efficient strategy to improve CRF in previously untrained women.
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Affiliation(s)
- Mary K Allison
- 1Department of Kinesiology, McMaster University, Hamilton, ON, CANADA; and 2School of Kinesiology and Health Studies, Queen's University, Kingston, ON, CANADA
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Aslankeser Z, Balcı ŞS. Re-examination of the contribution of substrates to energy expenditure during high-intensity intermittent exercise in endurance athletes. PeerJ 2017; 5:e3769. [PMID: 28894645 PMCID: PMC5591632 DOI: 10.7717/peerj.3769] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 08/16/2017] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND It has been believed that the contribution of fat oxidation to total energy expenditure is becoming negligible at higher exercise intensities (about 85% VO2max). The aim of the present study was to examine the changes in substrate oxidation during high-intensity interval exercise in young adult men. METHODS A total of 18 healthy well-trained (aged 19.60 ± 0.54 years, BMI = 22.19 ± 0.64 kg/m2, n = 10) and untrained (aged 20.25 ± 0.41 years, BMI = 22.78 ± 0.38 kg/m2, n = 8) young men volunteered to participate in this study. After an overnight fast, subjects were tested on a cycle ergometer and completed six 4-min bouts of cycling (at ∼80% VO2max) with 2 min of rests between intervals. Energy expenditure and the substrate oxidation rate were measured during the experiment by using indirect calorimetry. The blood lactate concentration was collected immediately after each interval workout. RESULTS The fat oxidation rate during each workout was significantly different between the untrained and the athlete groups (p < 0.05), and the carbohydrate (CHO) oxidation rate during the experiment was similar between groups (p > 0.05). Moreover, lactate concentration significantly increased in the untrained group (p < 0.05), whereas it did not significantly change in the athlete group during the workouts (p > 0.05). Fat contribution to energy expenditure was significantly higher in the athlete group (∼25%) than in the untrained group (∼2%). CONCLUSIONS The present study indicates that 17 times more fat oxidation was measured in the athlete group compared to the untrained group. However, the athletes had the same CHO oxidation rate as the recreationally active subjects during high-intensity intermittent exercise. Higher fat oxidation rate despite the same CHO oxidation rate may be related to higher performance in the trained group.
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Effects of Heart Rate vs. Speed-Based High Intensity Interval Training on Aerobic and Anaerobic Capacity of Female Soccer Players. Sports (Basel) 2017; 5:sports5030057. [PMID: 29910417 PMCID: PMC5968964 DOI: 10.3390/sports5030057] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2017] [Revised: 06/25/2017] [Accepted: 07/21/2017] [Indexed: 12/02/2022] Open
Abstract
The purpose of this study was to compare the effects of two types of high-intensity interval training (HIIT) programs on aerobic and anaerobic capacity of female soccer players. Regional-level female athletes were randomly divided into heart rate-based HIIT (n = 8; age 23.4 ± 1.1 year) and speed-based HIIT groups (n = 8; age 23.4 ± 1.3 year). Athletes trained three days per week for six weeks. Before and after training, each athlete’s performance was assessed directly through the Hoff test, 30-15 Intermittent Fitness Test (VIFT), and repeated-sprint ability test (RAST); maximal oxygen consumption (VO2max), power and fatigue were estimated indirectly. Both experimental groups improved power, fatigue index and VO2max after training (p < 0.05). It was noteworthy that the speed-based group had greater gains in minimal power (effect size (ES): 3.99 vs. 0.75), average power (ES: 2.23 vs. 0.33), and fatigue index (ES: 2.53 vs. 0.17) compared to heart rate-based group (p < 0.05). In conclusion, both heart rate-based and speed-based HIIT induced meaningful improvements in power, VO2max, and fatigue index in female soccer players, although the speed-based HIIT group achieved greater gains in power and fatigue index compared to the heart rate-based group.
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Messier FM, Le Moyec L, Santi C, Gaston AF, Triba MN, Roca E, Durand F. The impact of moderate altitude on exercise metabolism in recreational sportsmen: a nuclear magnetic resonance metabolomic approach. Appl Physiol Nutr Metab 2017; 42:1135-1141. [PMID: 28666093 DOI: 10.1139/apnm-2016-0717] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Although it is known that altitude impairs performance in endurance sports, there is no consensus on the involvement of energy substrates in this process. The objective of the present study was to determine whether the metabolomic pathways used during endurance exercise differ according to whether the effort is performed at sea level or at moderate altitude (at the same exercise intensity, using proton nuclear magnetic resonance, 1H NMR). Twenty subjects performed two 60-min endurance exercise tests at sea level and at 2150 m at identical relative intensity on a cycle ergometer. Blood plasma was obtained from venous blood samples drawn before and after exercise. 1H NMR spectral analysis was then performed on the plasma samples. A multivariate statistical technique was applied to the NMR data. The respective relative intensities of the sea level and altitude endurance tests were essentially the same when expressed as a percentage of the maximal oxygen uptake measured during the corresponding incremental maximal exercise test. Lipid use was similar at sea level and at altitude. In the plasma, levels of glucose, glutamine, alanine, and branched-chain amino acids had decreased after exercise at altitude but not after exercise at sea level. The decrease in plasma glucose and free amino acid levels observed after exercise at altitude indicated that increased involvement of the protein pathway was necessary but not sufficient for the maintenance of glycaemia. Metabolomics is a powerful means of gaining insight into the metabolic changes induced by exercise at altitude.
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Affiliation(s)
- Florian M Messier
- a Laboratoire Européen Performance Santé Altitude EA4604 - Université de Perpignan Via Domitia, Département STAPS, 7 Avenue Pierre de Coubertin, Font-Romeu, France
| | - Laurence Le Moyec
- b Unité de Biologie Intégrative et Adaptation à l'Exercice, EA 7362, Université d'Evry Val D'Essonne, Evry, France
| | - Carole Santi
- a Laboratoire Européen Performance Santé Altitude EA4604 - Université de Perpignan Via Domitia, Département STAPS, 7 Avenue Pierre de Coubertin, Font-Romeu, France
| | - Anne-Fleur Gaston
- a Laboratoire Européen Performance Santé Altitude EA4604 - Université de Perpignan Via Domitia, Département STAPS, 7 Avenue Pierre de Coubertin, Font-Romeu, France
| | - Mohamed N Triba
- c Chimie Structures Propriétés de Biomatériaux et d'Agents Thérapeutiques, CNRS UMR 7244, Université Paris 13 Sorbonne Paris Cité, Bobigny, France
| | - Emma Roca
- a Laboratoire Européen Performance Santé Altitude EA4604 - Université de Perpignan Via Domitia, Département STAPS, 7 Avenue Pierre de Coubertin, Font-Romeu, France.,d Facultat de Medicina, Universitat de Girona, C/Emili Grahit 77, Girona, Spain
| | - Fabienne Durand
- a Laboratoire Européen Performance Santé Altitude EA4604 - Université de Perpignan Via Domitia, Département STAPS, 7 Avenue Pierre de Coubertin, Font-Romeu, France
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Nugent FJ, Comyns TM, Warrington GD. Quality versus Quantity Debate in Swimming: Perceptions and Training Practices of Expert Swimming Coaches. J Hum Kinet 2017; 57:147-158. [PMID: 28713467 PMCID: PMC5504587 DOI: 10.1515/hukin-2017-0056] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The debate over low-volume, high-intensity training versus high-volume, low-intensity training, commonly known as Quality versus Quantity, respectively, is a frequent topic of discussion among swimming coaches and academics. The aim of this study was to explore expert coaches’ perceptions of quality and quantity coaching philosophies in competitive swimming and to investigate their current training practices. A purposeful sample of 11 expert swimming coaches was recruited for this study. The study was a mixed methods design and involved each coach participating in 1 semi-structured interview and completing 1 closed-ended questionnaire. The main findings of this study were that coaches felt quality training programmes would lead to short term results for youth swimmers, but were in many cases more appropriate for senior swimmers. The coaches suggested that quantity training programmes built an aerobic base for youth swimmers, promoted technical development through a focus on slower swimming and helped to enhance recovery from training or competition. However, the coaches continuously suggested that quantity training programmes must be performed with good technique and they felt this was a misunderstood element. This study was a critical step towards gaining a richer and broader understanding on the debate over Quality versus Quantity training from an expert swimming coaches’ perspective which was not currently available in the research literature.
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Affiliation(s)
- Frank J Nugent
- Department of Physical Education and Sport Sciences, University of Limerick, Limerick, Ireland
- Frank Nugent Department of Physical Education and Sport Sciences University of Limerick, Limerick, Ireland Phone: +353851506074
| | - Thomas M Comyns
- Department of Physical Education and Sport Sciences, University of Limerick, Limerick, Ireland
| | - Giles D Warrington
- Department of Physical Education and Sport Sciences, University of Limerick, Limerick, Ireland
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Nugent FJ, Comyns TM, Burrows E, Warrington GD. Effects of Low-Volume, High-Intensity Training on Performance in Competitive Swimmers: A Systematic Review. J Strength Cond Res 2017; 31:837-847. [DOI: 10.1519/jsc.0000000000001583] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Richer SD, Nolte VW, Bechard DJ, Belfry GR. Effects of Novel Supramaximal Interval Training Versus Continuous Training on Performance in Preconditioned Collegiate, National, and International Class Rowers. J Strength Cond Res 2016; 30:1752-62. [PMID: 27213500 DOI: 10.1519/jsc.0000000000001274] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Sylvie D Richer
- Canadian Centre for Activity and Aging Laboratory, School of Kinesiology, The University of Western Ontario, London, Ontario, Canada
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García-Pinillos F, Soto-Hermoso VM, Latorre-Román PÁ. Acute Physiological and Thermoregulatory Responses to Extended Interval Training in Endurance Runners: Influence of Athletic Performance and Age. J Hum Kinet 2015; 49:209-17. [PMID: 26839621 PMCID: PMC4723170 DOI: 10.1515/hukin-2015-0123] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/01/2015] [Indexed: 12/04/2022] Open
Abstract
This study aimed to describe the acute impact of extended interval training (EIT) on physiological and thermoregulatory levels, as well as to determine the influence of athletic performance and age effect on the aforementioned response in endurance runners. Thirty-one experienced recreational male endurance runners voluntarily participated in this study. Subjects performed EIT on an outdoor running track, which consisted of 12 runs of 400 m. The rate of perceived exertion, physiological response through the peak and recovery heart rate, blood lactate, and thermoregulatory response through tympanic temperature, were controlled. A repeated measures analysis revealed significant differences throughout EIT in examined variables. Cluster analysis grouped according to the average performance in 400 m runs led to distinguish between athletes with a higher and lower sports level. Cluster analysis was also performed according to age, obtaining an older group and a younger group. The one-way analysis of variance between groups revealed no significant differences (p≥0.05) in the response to EIT. The results provide a detailed description of physiological and thermoregulatory responses to EIT in experienced endurance runners. This allows a better understanding of the impact of a common training stimulus on the physiological level inducing greater accuracy in the training prescription. Moreover, despite the differences in athletic performance or age, the acute physiological and thermoregulatory responses in endurance runners were similar, as long as EIT was performed at similar relative intensity.
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Affiliation(s)
- Felipe García-Pinillos
- Faculty of Education Sciences. Department of Didactics of Corporal Expression. University of Jaén (Spain). Jaén (Spain)
- Corresponding author: Felipe García-Pinillos., Faculty of Education Sciences. Department of Didactics of Corporal Expression. University of Jaén (Spain)., Campus de las Lagunillas s/n, 23071, Jaén (Spain)., Phone: (+34) 660062066, Fax: (+34) 953 212710., E-mail:
| | - Víctor Manuel Soto-Hermoso
- Faculty of Sport Sciences. Department of Physical Education. University of Granada (Spain). Granada (Spain)
| | - Pedro Ángel Latorre-Román
- Faculty of Education Sciences. Department of Didactics of Corporal Expression. University of Jaén (Spain). Jaén (Spain)
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Boldingh AM, Jensen TH, Bjørbekk AT, Solevåg AL, Nakstad B. Rescuers' physical fatigue with different chest compression to ventilation methods during simulated infant cardiopulmonary resuscitation. J Matern Fetal Neonatal Med 2015; 29:3202-7. [PMID: 26566091 DOI: 10.3109/14767058.2015.1119115] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To assess development of objective, subjective and indirect measures of fatigue during simulated infant cardiopulmonary resuscitation (CPR) with two different methods. METHODS Using a neonatal manikin, 17 subject-pairs were randomized in a crossover design to provide 5-min CPR with a 3:1 chest compression (CC) to ventilation (C:V) ratio and continuous CCs at a rate of 120 min(-1) with asynchronous ventilations (CCaV-120). We measured participants' changes in heart rate (HR) and mean arterial pressure (MAP); perceived level of fatigue on a validated Likert scale; and manikin CC measures. RESULTS CCaV-120 compared with a 3:1 C:V ratio resulted in a change during 5-min of CPR in HR 49 versus 40 bpm (p = 0.01), and MAP 1.7 versus -2.8 mmHg (p = 0.03); fatigue rated on a Likert scale 12.9 versus 11.4 (p = 0.2); and a significant decay in CC depth after 90 s (p = 0.03). CONCLUSIONS The results indicate a trend toward more fatigue during simulated CPR in CCaV-120 compared to the recommended 3:1 C:V CPR. These results support current guidelines.
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Affiliation(s)
- Anne Marthe Boldingh
- a Department of Pediatric and Adolescent Medicine , Akershus University Hospital , Lørenskog , Norway and.,b Akershus Faculty Division, Institute of Clinical Medicine, University of Oslo , Lørenskog , Norway
| | - Thomas Hagen Jensen
- a Department of Pediatric and Adolescent Medicine , Akershus University Hospital , Lørenskog , Norway and
| | - Ane Torvik Bjørbekk
- a Department of Pediatric and Adolescent Medicine , Akershus University Hospital , Lørenskog , Norway and
| | - Anne Lee Solevåg
- a Department of Pediatric and Adolescent Medicine , Akershus University Hospital , Lørenskog , Norway and
| | - Britt Nakstad
- a Department of Pediatric and Adolescent Medicine , Akershus University Hospital , Lørenskog , Norway and.,b Akershus Faculty Division, Institute of Clinical Medicine, University of Oslo , Lørenskog , Norway
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Akca F, Aras D. Comparison of Rowing Performance Improvements Following Various High-Intensity Interval Trainings. J Strength Cond Res 2015; 29:2249-54. [DOI: 10.1519/jsc.0000000000000870] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Higgins TP, Baker MD, Evans SA, Adams RA, Cobbold C. Heterogeneous responses of personalised high intensity interval training on type 2 diabetes mellitus and cardiovascular disease risk in young healthy adults. Clin Hemorheol Microcirc 2015; 59:365-77. [DOI: 10.3233/ch-141857] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
| | | | - Shelley-Ann Evans
- School of Health Sciences, Cardiff Metropolitan University, Cardiff, UK
| | - Rachel A. Adams
- School of Health Sciences, Cardiff Metropolitan University, Cardiff, UK
| | - Christian Cobbold
- Faculty of Health Sciences and Medicine, Bond University, QLD, Australia
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Ye T, Pan X. A convenient prediction model for complete recovery time after exhaustion in high-intensity work. ERGONOMICS 2015; 58:1433-1444. [PMID: 25677862 DOI: 10.1080/00140139.2015.1008587] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
UNLABELLED We aimed to propose a convenient model for predicting complete recovery time (CRT) after exhaustion in high-intensity work. Before participating in the laboratory test, each of the 47 young adult subjects provided demographic information and filled out the perceived functional ability (PFA) and physical activity rating (PA-R) questionnaires. All subjects were required to perform one cycling test (at 70% maximum working capacity). Subjects continued cycling until exhaustion and then sat and recovered until their heart rates (HR) returned to baseline values. We found that CRT was significantly correlated with relative body mass index, the PFA score, PA-R score and maximum heart rate (HRmax). Accordingly, a prediction model for CRT was proposed. Furthermore, by replacing HRmax with age-predicted maximal HR, we obtained a more convenient prediction model that was independent of any physiological indexes that can only be obtained by subject testing. PRACTITIONER SUMMARY High-intensity work is associated with higher perceived fatigue, which can be alleviated after a rest period. Instead of complex laboratory testing, questionnaires were used to derive a convenient prediction model for CRT after exhaustion. Ergonomics should be incorporated into work–rest schedule planning to improve efficiency and safety.
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Affiliation(s)
- Taofeng Ye
- a Human Factors Laboratory, School of Economics & Management , Jiangsu University of Science & Technology , Zhenjiang , P.R. China
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Stanley J, Peake JM, Buchheit M. Cardiac parasympathetic reactivation following exercise: implications for training prescription. Sports Med 2014; 43:1259-77. [PMID: 23912805 DOI: 10.1007/s40279-013-0083-4] [Citation(s) in RCA: 240] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The objective of exercise training is to initiate desirable physiological adaptations that ultimately enhance physical work capacity. Optimal training prescription requires an individualized approach, with an appropriate balance of training stimulus and recovery and optimal periodization. Recovery from exercise involves integrated physiological responses. The cardiovascular system plays a fundamental role in facilitating many of these responses, including thermoregulation and delivery/removal of nutrients and waste products. As a marker of cardiovascular recovery, cardiac parasympathetic reactivation following a training session is highly individualized. It appears to parallel the acute/intermediate recovery of the thermoregulatory and vascular systems, as described by the supercompensation theory. The physiological mechanisms underlying cardiac parasympathetic reactivation are not completely understood. However, changes in cardiac autonomic activity may provide a proxy measure of the changes in autonomic input into organs and (by default) the blood flow requirements to restore homeostasis. Metaboreflex stimulation (e.g. muscle and blood acidosis) is likely a key determinant of parasympathetic reactivation in the short term (0-90 min post-exercise), whereas baroreflex stimulation (e.g. exercise-induced changes in plasma volume) probably mediates parasympathetic reactivation in the intermediate term (1-48 h post-exercise). Cardiac parasympathetic reactivation does not appear to coincide with the recovery of all physiological systems (e.g. energy stores or the neuromuscular system). However, this may reflect the limited data currently available on parasympathetic reactivation following strength/resistance-based exercise of variable intensity. In this review, we quantitatively analyse post-exercise cardiac parasympathetic reactivation in athletes and healthy individuals following aerobic exercise, with respect to exercise intensity and duration, and fitness/training status. Our results demonstrate that the time required for complete cardiac autonomic recovery after a single aerobic-based training session is up to 24 h following low-intensity exercise, 24-48 h following threshold-intensity exercise and at least 48 h following high-intensity exercise. Based on limited data, exercise duration is unlikely to be the greatest determinant of cardiac parasympathetic reactivation. Cardiac autonomic recovery occurs more rapidly in individuals with greater aerobic fitness. Our data lend support to the concept that in conjunction with daily training logs, data on cardiac parasympathetic activity are useful for individualizing training programmes. In the final sections of this review, we provide recommendations for structuring training microcycles with reference to cardiac parasympathetic recovery kinetics. Ultimately, coaches should structure training programmes tailored to the unique recovery kinetics of each individual.
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Affiliation(s)
- Jamie Stanley
- Centre of Excellence for Applied Sport Science Research, Queensland Academy of Sport, Brisbane, QLD, Australia,
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Time to exhaustion at continuous and intermittent maximal lactate steady state during running exercise. Int J Sports Physiol Perform 2013; 9:772-6. [PMID: 24235775 DOI: 10.1123/ijspp.2013-0403] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The purpose of this study was to determine and compare the time to exhaustion (TE) and the physiological responses at continuous and intermittent (ratio 5:1) maximal lactate steady state (MLSS) in well-trained runners. Ten athletes (32.7 ± 6.9 y, VO2max 61.7 ± 3.9 mL · kg-1 · min-1) performed an incremental treadmill test, three to five 30-min constant-speed tests to determine the MLSS continuous and intermittent (5 min of running, interspaced by 1 min of passive rest), and 2 randomized TE tests at such intensities. Two-way ANOVA with repeated measures was used to compare the changes in physiological variables during the TE tests and between continuous and intermittent exercise. The intermittent MLSS velocity (MLSSint = 15.26 ± 0.97 km/h) was higher than in the continuous model (MLSScon = 14.53 ± 0.93 km/h), while the TE at MLSScon was longer than MLSSint (68 ± 11 min and 58 ± 15 min, P < .05). Regarding the cardiorespiratory responses, VO2 and respiratory-exchange ratio remained stable during both TE tests while heart rate, ventilation, and rating of perceived exertion presented a significant increase in the last portion of the tests. The results showed a higher tolerance to exercising during MLSScon than during MLSSint in trained runners. Thus, the training volume of an extensive interval session (ratio 5:1) designed at MLSS intensity should take into consideration this higher speed at MLSS and also the lower TE than with continuous exercise.
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Etxebarria N, Anson JM, Pyne DB, Ferguson RA. High-intensity cycle interval training improves cycling and running performance in triathletes. Eur J Sport Sci 2013; 14:521-9. [DOI: 10.1080/17461391.2013.853841] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Jacobs RA, Flück D, Bonne TC, Bürgi S, Christensen PM, Toigo M, Lundby C. Improvements in exercise performance with high-intensity interval training coincide with an increase in skeletal muscle mitochondrial content and function. J Appl Physiol (1985) 2013; 115:785-93. [DOI: 10.1152/japplphysiol.00445.2013] [Citation(s) in RCA: 168] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Six sessions of high-intensity interval training (HIT) are sufficient to improve exercise capacity. The mechanisms explaining such improvements are unclear. Accordingly, the aim of this study was to perform a comprehensive evaluation of physiologically relevant adaptations occurring after six sessions of HIT to determine the mechanisms explaining improvements in exercise performance. Sixteen untrained (43 ± 6 ml·kg−1·min−1) subjects completed six sessions of repeated ( 8 – 12 ) 60 s intervals of high-intensity cycling (100% peak power output elicited during incremental maximal exercise test) intermixed with 75 s of recovery cycling at a low intensity (30 W) over a 2-wk period. Potential training-induced alterations in skeletal muscle respiratory capacity, mitochondrial content, skeletal muscle oxygenation, cardiac capacity, blood volumes, and peripheral fatigue resistance were all assessed prior to and again following training. Maximal measures of oxygen uptake (V̇o2peak; ∼8%; P = 0.026) and cycling time to complete a set amount of work (∼5%; P = 0.008) improved. Skeletal muscle respiratory capacities increased, most likely as a result of an expansion of skeletal muscle mitochondria (∼20%, P = 0.026), as assessed by cytochrome c oxidase activity. Skeletal muscle deoxygenation also increased while maximal cardiac output, total hemoglobin, plasma volume, total blood volume, and relative measures of peripheral fatigue resistance were all unaltered with training. These results suggest that increases in mitochondrial content following six HIT sessions may facilitate improvements in respiratory capacity and oxygen extraction, and ultimately are responsible for the improvements in maximal whole body exercise capacity and endurance performance in previously untrained individuals.
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Affiliation(s)
- Robert Acton Jacobs
- Zurich Center for Integrative Human Physiology (ZIHP), Zurich, Switzerland
- Institute of Physiology, University of Zurich, Zurich, Switzerland
- Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland:
| | - Daniela Flück
- Zurich Center for Integrative Human Physiology (ZIHP), Zurich, Switzerland
- Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Thomas Christian Bonne
- Department of Exercise and Sport Sciences, University of Copenhagen, Copenhagen, Denmark; and
| | - Simon Bürgi
- Institute of Physiology, University of Zurich, Zurich, Switzerland
| | | | - Marco Toigo
- Zurich Center for Integrative Human Physiology (ZIHP), Zurich, Switzerland
- Institute of Physiology, University of Zurich, Zurich, Switzerland
- Exercise Physiology, Institute of Human Movement Sciences, ETH Zurich, Zurich, Switzerland
| | - Carsten Lundby
- Zurich Center for Integrative Human Physiology (ZIHP), Zurich, Switzerland
- Institute of Physiology, University of Zurich, Zurich, Switzerland
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Gibala MJ, Little JP, Macdonald MJ, Hawley JA. Physiological adaptations to low-volume, high-intensity interval training in health and disease. J Physiol 2012; 590:1077-84. [PMID: 22289907 DOI: 10.1113/jphysiol.2011.224725] [Citation(s) in RCA: 921] [Impact Index Per Article: 76.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Exercise training is a clinically proven, cost-effective, primary intervention that delays and in many cases prevents the health burdens associated with many chronic diseases. However, the precise type and dose of exercise needed to accrue health benefits is a contentious issue with no clear consensus recommendations for the prevention of inactivity-related disorders and chronic diseases. A growing body of evidence demonstrates that high-intensity interval training (HIT) can serve as an effective alternate to traditional endurance-based training, inducing similar or even superior physiological adaptations in healthy individuals and diseased populations, at least when compared on a matched-work basis. While less well studied, low-volume HIT can also stimulate physiological remodelling comparable to moderate-intensity continuous training despite a substantially lower time commitment and reduced total exercise volume. Such findings are important given that 'lack of time' remains the most commonly cited barrier to regular exercise participation. Here we review some of the mechanisms responsible for improved skeletal muscle metabolic control and changes in cardiovascular function in response to low-volume HIT. We also consider the limited evidence regarding the potential application of HIT to people with, or at risk for, cardiometabolic disorders including type 2 diabetes. Finally, we provide insight on the utility of low-volume HIT for improving performance in athletes and highlight suggestions for future research.
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Affiliation(s)
- Martin J Gibala
- Department of Kinesiology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1 Canada.
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Enoksen E, Shalfawi SAI, Tønnessen E. The effect of high- vs. low-intensity training on aerobic capacity in well-trained male middle-distance runners. J Strength Cond Res 2011; 25:812-8. [PMID: 20647950 DOI: 10.1519/jsc.0b013e3181cc2291] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The purpose of this study was to examine the effect of 2 different intervention training regimes on VO2max, VO2max velocity (vVO2max), running economy (RE), lactic threshold velocity (vLT), and running performance on a group of well-trained male middle-distance runners in the precompetition period. Twenty-six well-trained male middle-distance runners took part in the study. All participants were tested on VO2max, vVO2max, RE, lactate threshold (LT), vLT, and a performance test. The participants were matched according to their pretest results, then randomly assigned into 1 of 2 groups, a high-volume (70 km) low-intensity training group (HVLI-group); or a high-intensity low-volume (50 km) training group (HILV-group). No significant differences were found between the 2 groups on all measures both before and after the intervention period. Furthermore, the HILV-group had a marked increase in vVO2max and vLT after the training period when compared with pretest. Both groups had a marked improvement in RE. The performance test showed that the HILV-group made 301 ± 886 m (1.0 ± 2.8 minutes) and the HVLI-group 218 ± 546 m (0.9 ± 1.8 minutes) in progress. The production of lactic acid was notably higher in the HILV-group (0.9 mmol) when compared with the pretest. The findings show that male middle-distance runners tested in this study improved in vVO2max and vLT more when they train around LT, than training with low intensity for a short period of 10 weeks.
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Affiliation(s)
- Eystein Enoksen
- Department of Physical Performance, The Norwegian School of Sport Sciences, Oslo, Norway.
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40
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Laursen PB. Training for intense exercise performance: high-intensity or high-volume training? Scand J Med Sci Sports 2011; 20 Suppl 2:1-10. [PMID: 20840557 DOI: 10.1111/j.1600-0838.2010.01184.x] [Citation(s) in RCA: 193] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Performance in intense exercise events, such as Olympic rowing, swimming, kayak, track running and track cycling events, involves energy contribution from aerobic and anaerobic sources. As aerobic energy supply dominates the total energy requirements after ∼75s of near maximal effort, and has the greatest potential for improvement with training, the majority of training for these events is generally aimed at increasing aerobic metabolic capacity. A short-term period (six to eight sessions over 2-4 weeks) of high-intensity interval training (consisting of repeated exercise bouts performed close to or well above the maximal oxygen uptake intensity, interspersed with low-intensity exercise or complete rest) can elicit increases in intense exercise performance of 2-4% in well-trained athletes. The influence of high-volume training is less discussed, but its importance should not be downplayed, as high-volume training also induces important metabolic adaptations. While the metabolic adaptations that occur with high-volume training and high-intensity training show considerable overlap, the molecular events that signal for these adaptations may be different. A polarized approach to training, whereby ∼75% of total training volume is performed at low intensities, and 10-15% is performed at very high intensities, has been suggested as an optimal training intensity distribution for elite athletes who perform intense exercise events.
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Affiliation(s)
- P B Laursen
- New Zealand Academy of Sport, Auckland, New Zealand.
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Sarpeshkar V, Bentley DJ. Adrenergic-β2 receptor polymorphism and athletic performance. J Hum Genet 2010; 55:479-85. [DOI: 10.1038/jhg.2010.42] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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42
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The effect of carbohydrate ingestion on the interleukin-6 response to a 90-minute run time trial. Int J Sports Physiol Perform 2009; 4:186-94. [PMID: 19567922 DOI: 10.1123/ijspp.4.2.186] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Fatigue is a predictable outcome of prolonged physical activity; yet its biological cause remains uncertain. During exercise, a polypeptide messenger molecule interleukin- 6 (IL-6) is actively produced. Previously, it has been demonstrated that administration of recombinant IL-6 (rhIL-6) impairs 10-km run performance and heightened sensation of fatigue in trained runners. Both high carbohydrate diets and carbohydrate ingestion during prolonged exercise have a blunting effect on IL-6 levels postendurance exercise. We hypothesized that carbohydrate ingestion may improve performance during a prolonged bout of exercise as a consequence of a blunted IL-6 response. Seven recreationally trained fasted runners completed two 90-min time trials under CHO supplemented and placebo conditions in a randomized order. The study was of a double-blinded, placebo-controlled, cross-over study design. Distance covered in 90 min was significantly greater following exogenous carbohydrate ingestion compared with the placebo trial (19.13+/-1.7 km and 18.29+/-1.9 km, respectively, p=.0022). While postexercise IL-6 levels were significantly lower in the CHO trial compared with the placebo trial (5.3+/-1.9 pg.mL(-1) and 6.6+/-3.0 pg.mL(-1), respectively; p=.0313), this difference was considered physiologically too small to mediate the improvement in time trial performance.
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Swart J, Lamberts RP, Derman W, Lambert MI. Effects of high-intensity training by heart rate or power in well-trained cyclists. J Strength Cond Res 2009; 23:619-25. [PMID: 19204572 DOI: 10.1519/jsc.0b013e31818cc5f5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The aim of this study was to determine whether the performance of cyclists after 4 weeks of high-intensity training improved similarly using either heart rate or power to prescribe training. Twenty-one well-trained men cyclists (age, 32 +/- 6 years; peak power output, 371 +/- 46 W) were randomly assigned to a power-based (GPOWER) or heart rate-based (GHEART) high-intensity training (HIT) group or a control group (GCONTROL). Training consisted of 8 repetitions of 4 minutes at either 80% of peak power output (GPOWER) or at the heart rate coinciding with 80% of peak power output (GHEART), with rest periods of 90 seconds. A 40-km time trial and VO2max test were performed before and after 8 training sessions. There were significant improvements (p < 0.05) in peak power output (GPOWER = 3.5%; GHEART = 5.0%) and 40-km time trial performance (GPOWER = 2.3%; GHEART = 2.1%) for both of the high-intensity groups. Although there were no significant differences between groups for these variables, when the data were analyzed using magnitude-based effects, the GHEART group showed greater probability of a "beneficial" effect for peak power output. The current general perception that prescribing training based only on power is more effective than prescribing training based on heart rate was not supported by the data from this study. Coaches who are unable to monitor progress frequently should prescribe training based on heart rate, when intervals are performed under stable conditions, because this may provide an additional advantage over prescribing training using power.
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Affiliation(s)
- Jeroen Swart
- Department of Human Biology, Faculty of Health Sciences, UCT/MRC Research Unit for Exercise Science and Sports Medicine, University of Cape Town, The Sport Science Institute of South Africa, Newlands, South Africa.
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The Effects of High-Intensity Interval Training in Well-Trained Rowers. Int J Sports Physiol Perform 2009; 4:110-21. [DOI: 10.1123/ijspp.4.1.110] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Purpose:Several recent studies have reported substantial performance and physiological gains in well-trained endurance runners, swimmers, and cyclists following a period of high-intensity interval training (HIT). The aim of the current study was to compare traditional rowing training (CT) to HIT in well-trained rowers.Methods:Subjects included 5 male and 5 female rowers (mean ± SD; age = 19 ± 2 y; height = 176 ± 8 cm; mass = 73.7 ± 9.8 kg; Vo2peak = 4.37 ± 1.08 L·min−1). Baseline testing included a 2000-m time trial and a maximal exercise test to determine Vo2peak, 4-min all-out power, and 4 mmol·L−1 blood lactate threshold. Following baseline testing, rowers were randomly allocated to HIT or CT, which they performed seven times over a 4-wk period. The HIT involved 8 × 2.5-min intervals at 90% of the velocity maintained at Vo2peak, with individual recoveries returning to 70% of the subjects’ maximal heart rate between intervals. The CT intensity consisted of workloads corresponding to 2 and 3 mmol·L−1 blood lactate concentrations. On completion of HIT or CT, rowers repeated the testing performed at baseline and were then allocated to the alternative training program and completed a crossover trial.Results:HIT produced greater improvements in 2000-m time (1.9 ± 0.9%; mean ± SD), 2000-m power (5.8 ± 3.0%), and relative Vo2peak (7.0 ± 6.4%) than CT.Conclusion:Four weeks of HIT improves 2000-m time-trial performance and relative Vo2peak in competitive rowers, more than a traditional approach.
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Sidhu SK, Bentley DJ, Carroll TJ. Locomotor exercise induces long-lasting impairments in the capacity of the human motor cortex to voluntarily activate knee extensor muscles. J Appl Physiol (1985) 2008; 106:556-65. [PMID: 19056999 DOI: 10.1152/japplphysiol.90911.2008] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Muscle fatigue is a reduction in the capacity to exert force and may involve a "central" component originating in the brain and/or spinal cord. Here we examined whether supraspinal factors contribute to impaired central drive after locomotor endurance exercise. On 2 separate days, 10 moderately active individuals completed a locomotor cycling exercise session or a control session. Brief (2 s) and sustained (30 s) isometric knee extension contractions were completed before and after locomotor exercise consisting of eight, 5-min bouts of cycling at 80% of maximum workload. In the control session, subjects completed the isometric contractions in a rested state. Twitch responses to supramaximal motor nerve stimulation and transcranial magnetic stimulation were obtained to assess peripheral force-generating capacity and voluntary activation. Maximum voluntary contraction (MVC) force during brief contractions decreased by 23 +/- 6.3% after cycling exercise and remained 12 +/- 2.8% below baseline 45 min later (F(1,9) > 15.5; P < 0.01). Resting twitch amplitudes declined by approximately 45% (F(1,9) = 28.3; P < 0.001). Cortical voluntary activation declined from 90.6 +/- 1.6% at baseline to 80.6 +/- 2.1% after exercise (F(1,9) = 28.0; P < 0.001) and remained significantly reduced relative to control 30-45 min later (80.6 +/- 3.4%; F(1,9) = 10.7; P < 0.01). Thus locomotor exercise caused a long-lasting impairment in the capacity of the motor cortex to drive the knee extensors. Force was reduced more during sustained MVC after locomotor exercise than in the control session. Peripheral mechanisms contributed relatively more to this force reduction in the control session, whereas supraspinal fatigue played a greater role in sustained MVC reduction after locomotor exercise.
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Loprinzi PD, Brodowicz GR. Physiological adaptations and analysis of training content in high school cross-country runners. Res Sports Med 2008; 16:189-202. [PMID: 18785061 DOI: 10.1080/15438620802104054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The purposes of this study were to examine effects of a season of training on aerobic performance in cross-country distance runners and to analyze the training using subjective and objective techniques. Subjects averaged 184 minutes of running per week, with 45%, 24%, and 31% occurring in zones below, near, and above the heart rate (HR) corresponding to ventilatory threshold (VT(HR)), respectively (Zone 1: HR > 15 bpm below VT(HR); Zone 2: HR between Zone 1 and VT(HR); Zone 3: HR > VT(HR)). Maximal oxygen uptake (VO(2 max)) increased by 5.1%, 5-km race time by 46 seconds (3.7%), and 2-km time trial performance by 54 seconds (10.7%) from pre- to postseason. Results are similar to previous research demonstrating that short-term (< 3 months) endurance training elicits improvements in various physiological parameters. Findings were not consistent with previous research that suggests a discrepancy may exist between the runners' perceptions and the physiological effects of their training.
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Affiliation(s)
- Paul D Loprinzi
- Physical Activity Assessment Laboratory, Department of Nutrition and Exercise Sciences, Oregon State University, Corvallis, Oregon, USA
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Abstract
One of the consequences of sustaining exercise for 90 minutes of football match-play is that the capability of muscle to generate force declines. This impairment is reflected in the decline of work-rate towards the late part of the game. Causes of this phenomenon, which is known as fatigue, and some of its consequences are considered in this article. The stores of muscle glycogen may be considerably reduced by the end of the game, especially if there has not been a tapering of the training load. Thermoregulatory strain may also be encountered, resulting in a fall in physical performance, or there may be a reduced central drive from the nervous system. The decline in muscle strength may increase the predisposition to injury in the lower limbs. Central fatigue may also occur with implications for muscle performance. Strategies to offset fatigue include astute use of substitutions, appropriate nutritional preparation and balancing pre-cooling and warm-up procedures. There is also a role for endurance training and for a pacing strategy that optimizes the expenditure of energy during match-play.
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Affiliation(s)
- Thomas Reilly
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK.
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Midgley AW, McNaughton LR, Jones AM. Training to enhance the physiological determinants of long-distance running performance: can valid recommendations be given to runners and coaches based on current scientific knowledge? Sports Med 2008; 37:857-80. [PMID: 17887811 DOI: 10.2165/00007256-200737100-00003] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
This article investigates whether there is currently sufficient scientific knowledge for scientists to be able to give valid training recommendations to long-distance runners and their coaches on how to most effectively enhance the maximal oxygen uptake, lactate threshold and running economy. Relatively few training studies involving trained distance runners have been conducted, and these studies have often included methodological factors that make interpretation of the findings difficult. For example, the basis of most of the studies was to include one or more specific bouts of training in addition to the runners' 'normal training', which was typically not described or only briefly described. The training status of the runners (e.g. off-season) during the study period was also typically not described. This inability to compare the runners' training before and during the training intervention period is probably the main factor that hinders the interpretation of previous training studies. Arguably, the second greatest limitation is that only a few of the studies included more than one experimental group. Consequently, there is no comparison to allow the evaluation of the relative efficacy of the particular training intervention. Other factors include not controlling the runners' training load during the study period, and employing small sample sizes that result in low statistical power. Much of the current knowledge relating to chronic adaptive responses to physical training has come from studies using sedentary individuals; however, directly applying this knowledge to formulate training recommendations for runners is unlikely to be valid. Therefore, it would be difficult to argue against the view that there is insufficient direct scientific evidence to formulate training recommendations based on the limited research. Although direct scientific evidence is limited, we believe that scientists can still formulate worthwhile training recommendations by integrating the information derived from training studies with other scientific knowledge. This knowledge includes the acute physiological responses in the various exercise domains, the structures and processes that limit the physiological determinants of long-distance running performance, and the adaptations associated with their enhancement. In the future, molecular biology may make an increasing contribution in identifying effective training methods, by identifying the genes that contribute to the variation in maximal oxygen uptake, the lactate threshold and running economy, as well as the biochemical and mechanical signals that induce these genes. Scientists should be cautious when giving training recommendations to runners and coaches based on the limited available scientific knowledge. This limited knowledge highlights that characterising the most effective training methods for long-distance runners is still a fruitful area for future research.
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Affiliation(s)
- Adrian W Midgley
- Department of Sport, Health and Exercise Science, University of Hull, Hull, England.
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Thevenet D, Tardieu M, Zouhal H, Jacob C, Abderrahman BA, Prioux J. Influence of exercise intensity on time spent at high percentage of maximal oxygen uptake during an intermittent session in young endurance-trained athletes. Eur J Appl Physiol 2007; 102:19-26. [PMID: 17851682 DOI: 10.1007/s00421-007-0540-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/18/2007] [Indexed: 11/28/2022]
Abstract
The purpose of this study was to compare, during a 30s intermittent exercise (IE), the effects of exercise intensity on time spent above 90% VO2max(t90VO2max) and time spent above 95% VO2max(t95VO2max) in young endurance trained athletes. We hypothesized that during a 30sIE, an increase in exercise intensity would allow an increase in t90VO2max and t95VO2max due to a decrease in time to achieve 90% or 95% of VO2max. Nine endurance-trained male adolescents took part in three field tests. After determination of their VO2max and maximal aerobic velocity (MAV), they performed, until exhaustion, two intermittent exercise sessions alternating 30s at 100% of MAV (IE(100)) or 110% of MAV (IE(110)) and 30s at 50% of MAV. Mean time to exhaustion (t (lim)) values obtained during IE(100) were significantly longer than during IE(110) (p < 0.01). Moreover, no significant difference was found in t90VO2max or t95VO2max) expressed in absolute or relative (%t (lim)) values between IE(100) and IE(110). In conclusion, an increased of 10% of exercise intensity during a 30s intermittent exercise model (with active recovery), does not seem to be the most efficient exercise to solicit oxygen uptake to its highest level in young endurance-trained athletes.
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Affiliation(s)
- Delphine Thevenet
- Laboratoire (Motricitè, Interactions, Performance) (JE n2438), UFR STAPS, Nantes Cedex, France.
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Abstract
Physiological variables, such as maximum work rate or maximal oxygen uptake (VO2max), together with other submaximal metabolic inflection points (e.g. the lactate threshold [LT], the onset of blood lactate accumulation and the pulmonary ventilation threshold [VT]), are regularly quantified by sports scientists during an incremental exercise test to exhaustion. These variables have been shown to correlate with endurance performance, have been used to prescribe exercise training loads and are useful to monitor adaptation to training. However, an incremental exercise test can be modified in terms of starting and subsequent work rates, increments and duration of each stage. At the same time, the analysis of the blood lactate/ventilatory response to incremental exercise may vary due to the medium of blood analysed and the treatment (or mathematical modelling) of data following the test to model the metabolic inflection points. Modification of the stage duration during an incremental exercise test may influence the submaximal and maximal physiological variables. In particular, the peak power output is reduced in incremental exercise tests that have stages of longer duration. Furthermore, the VT or LT may also occur at higher absolute exercise work rate in incremental tests comprising shorter stages. These effects may influence the relationship of the variables to endurance performance or potentially influence the sensitivity of these results to endurance training. A difference in maximum work rate with modification of incremental exercise test design may change the validity of using these results for predicting performance, and prescribing or monitoring training. Sports scientists and coaches should consider these factors when conducting incremental exercise testing for the purposes of performance diagnostics.
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Affiliation(s)
- David J Bentley
- School of Medical Sciences, Health and Exercise Science, The University of New South Wales, Sydney, New South Wales, Australia.
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