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Mountjoy M, Ackerman KE, Bailey DM, Burke LM, Constantini N, Hackney AC, Heikura IA, Melin A, Pensgaard AM, Stellingwerff T, Sundgot-Borgen JK, Torstveit MK, Jacobsen AU, Verhagen E, Budgett R, Engebretsen L, Erdener U. 2023 International Olympic Committee's (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs). Br J Sports Med 2023; 57:1073-1097. [PMID: 37752011 DOI: 10.1136/bjsports-2023-106994] [Citation(s) in RCA: 45] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/20/2023] [Indexed: 09/28/2023]
Abstract
Relative Energy Deficiency in Sport (REDs) was first introduced in 2014 by the International Olympic Committee's expert writing panel, identifying a syndrome of deleterious health and performance outcomes experienced by female and male athletes exposed to low energy availability (LEA; inadequate energy intake in relation to exercise energy expenditure). Since the 2018 REDs consensus, there have been >170 original research publications advancing the field of REDs science, including emerging data demonstrating the growing role of low carbohydrate availability, further evidence of the interplay between mental health and REDs and more data elucidating the impact of LEA in males. Our knowledge of REDs signs and symptoms has resulted in updated Health and Performance Conceptual Models and the development of a novel Physiological Model. This Physiological Model is designed to demonstrate the complexity of either problematic or adaptable LEA exposure, coupled with individual moderating factors, leading to changes in health and performance outcomes. Guidelines for safe and effective body composition assessment to help prevent REDs are also outlined. A new REDs Clinical Assessment Tool-Version 2 is introduced to facilitate the detection and clinical diagnosis of REDs based on accumulated severity and risk stratification, with associated training and competition recommendations. Prevention and treatment principles of REDs are presented to encourage best practices for sports organisations and clinicians. Finally, methodological best practices for REDs research are outlined to stimulate future high-quality research to address important knowledge gaps.
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Affiliation(s)
- Margo Mountjoy
- Family Medicine, McMaster University Michael G DeGroote School of Medicine, Waterloo, Ontario, Canada
- Games Group, International Olympic Committee, Lausanne, Switzerland
| | - Kathryn E Ackerman
- Wu Tsai Female Athlete Program, Harvard Medical School, Boston Children's Hospital, Boston, Massachusetts, USA
| | | | - Louise M Burke
- Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, Victoria, Australia
| | - Naama Constantini
- Sports Medicine Center, Shaare Zedek Medical Center, The Hebrew University, Jerusalem, Israel
| | - Anthony C Hackney
- Exercise and Sport Science, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Ida Aliisa Heikura
- Canada Sport Institute Pacific, Victoria, British Columbia, Canada
- Exercise Science, Physical & Health Education, University of Victoria, Victoria, British Columbia, Canada
| | - Anna Melin
- Department of Sport Science - Swedish Olympic Committee Research Fellow, Linnaeus University, Kalmar, Sweden
| | - Anne Marte Pensgaard
- Department of Sport and Social Sciences, Norwegian School of Sports Sciences, Oslo, Norway
| | - Trent Stellingwerff
- Canada Sport Institute Pacific, Victoria, British Columbia, Canada
- Exercise Science, Physical & Health Education, University of Victoria, Victoria, British Columbia, Canada
| | | | | | | | - Evert Verhagen
- Amsterdam Collaboration on Health & Safety in Sports, Department of Public and Occupational Health, Amsterdam Movement Science, Amsterdam UMC Locatie VUmc, Amsterdam, The Netherlands
| | - Richard Budgett
- Medical and Scientific Department, International Olympic Committee, Lausanne, Switzerland
| | - Lars Engebretsen
- Medical and Scientific Department, International Olympic Committee, Lausanne, Switzerland
| | - Uğur Erdener
- Department of Ophthalmology, Hacettepe University, Ankara, Turkey
- World Archery, Lausanne, Switzerland
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Ackerman KE, Rogers MA, Heikura IA, Burke LM, Stellingwerff T, Hackney AC, Verhagen E, Schley S, Saville GH, Mountjoy M, Holtzman B. Methodology for studying Relative Energy Deficiency in Sport (REDs): a narrative review by a subgroup of the International Olympic Committee (IOC) consensus on REDs. Br J Sports Med 2023; 57:1136-1147. [PMID: 37752010 DOI: 10.1136/bjsports-2023-107359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/18/2023] [Indexed: 09/28/2023]
Abstract
In the past decade, the study of relationships among nutrition, exercise and the effects on health and athletic performance, has substantially increased. The 2014 introduction of Relative Energy Deficiency in Sport (REDs) prompted sports scientists and clinicians to investigate these relationships in more populations and with more outcomes than had been previously pursued in mostly white, adolescent or young adult, female athletes. Much of the existing physiology and concepts, however, are either based on or extrapolated from limited studies, and the comparison of studies is hindered by the lack of standardised protocols. In this review, we have evaluated and outlined current best practice methodologies to study REDs in an attempt to guide future research.This includes an agreement on the definition of key terms, a summary of study designs with appropriate applications, descriptions of best practices for blood collection and assessment and a description of methods used to assess specific REDs sequelae, stratified as either Preferred, Used and Recommended or Potential Researchers can use the compiled information herein when planning studies to more consistently select the proper tools to investigate their domain of interest. Thus, the goal of this review is to standardise REDs research methods to strengthen future studies and improve REDs prevention, diagnosis and care.
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Affiliation(s)
- Kathryn E Ackerman
- Wu Tsai Female Athlete Program, Division of Sports Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Margot Anne Rogers
- Australian Institute of Sport, Bruce, South Australia, Australia
- University of Canberra Research Institute for Sport and Exercise (UCRISE), Canberra, Australian Capital Territory, Australia
| | - Ida A Heikura
- Canadian Sport Institute-Pacific, Victoria, British Columbia, Canada
- Department of Exercise Science, Physical & Health Education, University of Victoria, Victoria, British Columbia, Canada
| | - Louise M Burke
- Mary McKillop Institute for Health Research, Australian Catholic University, Melbourne, Victoria, Australia
| | - Trent Stellingwerff
- Canadian Sport Institute-Pacific, Victoria, British Columbia, Canada
- Department of Exercise Science, Physical & Health Education, University of Victoria, Victoria, British Columbia, Canada
| | - Anthony C Hackney
- Exercise and Sport Science, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Evert Verhagen
- Amsterdam Collaboration on Health and Safety in Sports and Department of Public and Occupational Health, VU University Medical Center, Amsterdam, The Netherlands
| | - Stacey Schley
- Wu Tsai Female Athlete Program, Division of Sports Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Grace H Saville
- Wu Tsai Female Athlete Program, Division of Sports Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Margo Mountjoy
- Family Medicine, McMaster University Michael G DeGroote School of Medicine, Waterloo, Ontario, Canada
- Games Group, International Olympic Committee, Lausanne, Switzerland
| | - Bryan Holtzman
- Wu Tsai Female Athlete Program, Division of Sports Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
- Department of Pediatrics, Mass General for Children, Boston, Massachusetts, USA
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Lynch AE, Davies RW, Jakeman PM, Locke T, Allardyce JM, Carson BP. The Influence of Maximal Strength and Knee Angle on the Reliability of Peak Force in the Isometric Squat. Sports (Basel) 2021; 9:sports9100140. [PMID: 34678921 PMCID: PMC8539608 DOI: 10.3390/sports9100140] [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: 07/20/2021] [Revised: 09/17/2021] [Accepted: 10/02/2021] [Indexed: 11/16/2022] Open
Abstract
This study aimed to investigate the test-retest reliability of peak force in the isometric squat across the strength spectrum using coefficient of variation (CV) and intra-class correlation coefficient (ICC). On two separate days, 59 healthy men (mean (SD) age 23.0 (4.1) years; height 1.79 (0.7) m; body mass 84.0 (15.2) kg) performed three maximal effort isometric squats in two positions (at a 120° and a 90° knee angle). Acceptable reliability was observed at both the 120° (CV = 7.5 (6.7), ICC = 0.960 [0.933, 0.977]) and 90° positions (CV = 9.2 (8.8), ICC = 0.920 [0.865, 0.953]). There was no relationship between peak force in the isometric squat and the test-retest reliability at either the 120° (r = 0.052, p = 0.327) or 90° (r = 0.014, p = 0.613) positions. A subgroup of subjects (n = 17) also completed the isometric squat test at a 65° knee angle. Acceptable reliability was observed in this position (CV = 9.6 (9.3), ICC = 0.916 [0.766, 0.970]) and reliability was comparable to the 120° and 90° positions. Therefore, we deem isometric squat peak force output to be a valid and reliable measure across the strength spectrum and in different isometric squat positions.
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Affiliation(s)
- Arthur E. Lynch
- Department of Physical Education and Sport Sciences, Faculty of Education and Health Sciences, University of Limerick, V94 T9PX Limerick, Ireland; (A.E.L.); (R.W.D.); (P.M.J.); (T.L.); (J.M.A.)
| | - Robert W. Davies
- Department of Physical Education and Sport Sciences, Faculty of Education and Health Sciences, University of Limerick, V94 T9PX Limerick, Ireland; (A.E.L.); (R.W.D.); (P.M.J.); (T.L.); (J.M.A.)
| | - Philip M. Jakeman
- Department of Physical Education and Sport Sciences, Faculty of Education and Health Sciences, University of Limerick, V94 T9PX Limerick, Ireland; (A.E.L.); (R.W.D.); (P.M.J.); (T.L.); (J.M.A.)
| | - Tim Locke
- Department of Physical Education and Sport Sciences, Faculty of Education and Health Sciences, University of Limerick, V94 T9PX Limerick, Ireland; (A.E.L.); (R.W.D.); (P.M.J.); (T.L.); (J.M.A.)
| | - Joanna M. Allardyce
- Department of Physical Education and Sport Sciences, Faculty of Education and Health Sciences, University of Limerick, V94 T9PX Limerick, Ireland; (A.E.L.); (R.W.D.); (P.M.J.); (T.L.); (J.M.A.)
- Health Research Institute, University of Limerick, V94 T9PX Limerick, Ireland
| | - Brian P. Carson
- Department of Physical Education and Sport Sciences, Faculty of Education and Health Sciences, University of Limerick, V94 T9PX Limerick, Ireland; (A.E.L.); (R.W.D.); (P.M.J.); (T.L.); (J.M.A.)
- Health Research Institute, University of Limerick, V94 T9PX Limerick, Ireland
- Correspondence: ; Tel.: +353-(0)61-234943
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The Effect of Concurrent Resistance Training on Upper Body Strength, Sprint Swimming Performance and Kinematics in Competitive Adolescent Swimmers. A Randomized Controlled Trial. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph181910261. [PMID: 34639560 PMCID: PMC8508303 DOI: 10.3390/ijerph181910261] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 09/08/2021] [Accepted: 09/12/2021] [Indexed: 11/17/2022]
Abstract
This study aimed to examine the effect of 9 weeks of concurrent resistance training (CRT) between resistance on dry land (bench press (BP) and medicine ball throw) and resistance in water (water parachute and hand paddles) on muscle strength, sprint swimming performance and kinematic variables compared by the usual training (standard in-water training). Twenty-two male competitive swimmers participated in this study and were randomly allocated to two groups. The CRT group (CRTG, age = 16.5 ± 0.30 years) performed a CRT program, and the control group (CG, age = 16.1 ± 0.32 years) completed their usual training. The independent variables were measured pre- and post-intervention. The findings showed that the one-repetition maximum bench press (1RM BP) was improved only after a CRT program (d = 2.18; +12.11 ± 1.79%). Moreover, all sprint swimming performances were optimized in the CRT group (d = 1.3 to 2.61; −4.22 ± 0.18% to −7.13 ± 0.23%). In addition, the findings revealed an increase in velocity and stroke rate (d = 1.67, d = 2.24; 9.36 ± 2.55%, 13.51 ± 4.22%, respectively) after the CRT program. The CRT program improved the muscle strength, which, in turn, improved the stroke rate, with no change in the stroke length. Then, the improved stroke rate increased the swimming velocity. Ultimately, a faster velocity leads to better swim performances.
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Altan E, Seide S, Bayram I, Gizzi L, Ertan H, Röhrle O. A Systematic Review and Meta-Analysis on the Longitudinal Effects of Unilateral Knee Extension Exercise on Muscle Strength. Front Sports Act Living 2020; 2:518148. [PMID: 33345109 PMCID: PMC7739592 DOI: 10.3389/fspor.2020.518148] [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: 02/26/2020] [Accepted: 10/09/2020] [Indexed: 12/29/2022] Open
Abstract
The aim of the study was to investigate the time-dependent increase in the knee extensors' isometric strength as a response to voluntary, unilateral, isometric knee extension exercise (UIKEE). To do so, a systematic review was carried out to obtain data for a Bayesian longitudinal model-based meta-analysis (BLMBMA). For the systematic review, PubMed, Web of Science, SCOPUS, Chochrane Library were used as databases. The systematic review included only studies that reported on healthy, young individuals performing UIKEE. Studies utilizing a bilateral training protocol were excluded as the focus of this review lied on unilateral training. Out of the 3,870 studies, which were reviewed, 20 studies fulfilled the selected inclusion criteria. These 20 studies were included in the BLMBMA to investigate the time-dependent effects of UIKEE. If compared to the baseline strength of the trained limb, these data reveal that UKIEE can increase the isometric strength by up to 46%. A meta-analysis based on the last time-point of each available study was employed to support further investigations into UIKEE-induced strength increase. A sensitivity analysis showed that intensity of training (%MVC), fraction of male subjects and the average age of the subject had no significant influence on the strength gain. Convergence of BLMBMA revealed that the peak strength increase is reached after ~4 weeks of UIKEE training.
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Affiliation(s)
- Ekin Altan
- Department of Continuum Biomechanics and Mechanobiology, Institute for Modeling and Simulation of Biomechanical Systems, University of Stuttgart, Stuttgart, Germany
| | - Svenja Seide
- Institute of Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany
| | - Ismail Bayram
- Department of Coach Training in Sports, Faculty of Sport Sciences, Eskisehir Technical University, Eskisehir, Turkey
| | - Leonardo Gizzi
- Department of Continuum Biomechanics and Mechanobiology, Institute for Modeling and Simulation of Biomechanical Systems, University of Stuttgart, Stuttgart, Germany
| | - Hayri Ertan
- Department of Coach Training in Sports, Faculty of Sport Sciences, Eskisehir Technical University, Eskisehir, Turkey
| | - Oliver Röhrle
- Department of Continuum Biomechanics and Mechanobiology, Institute for Modeling and Simulation of Biomechanical Systems, University of Stuttgart, Stuttgart, Germany.,Coaching Education Department, Faculty of Sport Sciences, Eskisehir Technical University, Eskisehir, Turkey
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Grgic J, Lazinica B, Schoenfeld BJ, Pedisic Z. Test-Retest Reliability of the One-Repetition Maximum (1RM) Strength Assessment: a Systematic Review. SPORTS MEDICINE-OPEN 2020; 6:31. [PMID: 32681399 PMCID: PMC7367986 DOI: 10.1186/s40798-020-00260-z] [Citation(s) in RCA: 103] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 07/06/2020] [Indexed: 12/28/2022]
Abstract
Background The test–retest reliability of the one-repetition maximum (1RM) test varies across different studies. Given the inconsistent findings, it is unclear what the true reliability of the 1RM test is, and to what extent it is affected by measurement-related factors, such as exercise selection for the test, the number of familiarization trials and resistance training experience. Objectives The aim of this paper was to review studies that investigated the reliability of the 1RM test of muscular strength and summarize their findings. Methods The PRISMA guidelines were followed for this systematic review. Searches for studies were conducted through eight databases. Studies that investigated test–retest reliability of the 1RM test and presented intra-class correlation coefficient (ICC) and/or coefficient of variation (CV) were included. The COSMIN checklist was used for the assessment of the methodological quality of the included studies. Results After reviewing 1024 search records, 32 studies (pooled n = 1595) on test–retest reliability of 1RM assessment were found. All the studies were of moderate or excellent methodological quality. Test–retest ICCs ranged from 0.64 to 0.99 (median ICC = 0.97), where 92% of ICCs were ≥ 0.90, and 97% of ICCs were ≥ 0.80. The CVs ranged from 0.5 to 12.1% (median CV = 4.2%). ICCs were generally high (≥ 0.90), and most CVs were low (< 10%) for 1RM tests: (1) among those without and for those with some resistance training experience, (2) conducted with or without familiarization sessions, (3) with single-joint or multi-joint exercises, (4) for upper- and lower-body strength assessment, (5) among females and males, and (6) among young to middle-aged adults and among older adults. Most studies did not find systematic changes in test results between the trials. Conclusions Based on the results of this review, it can be concluded that the 1RM test generally has good to excellent test–retest reliability, regardless of resistance training experience, number of familiarization sessions, exercise selection, part of the body assessed (upper vs. lower body), and sex or age of participants. Researchers and practitioners, therefore, can use the 1RM test as a reliable test of muscular strength.
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Affiliation(s)
- Jozo Grgic
- Institute for Health and Sport (IHES), Victoria University, Melbourne, Australia
| | - Bruno Lazinica
- Faculty of Education, Department of Kinesiology, J.J. Strossmayer University, Osijek, Croatia
| | | | - Zeljko Pedisic
- Institute for Health and Sport (IHES), Victoria University, Melbourne, Australia.
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Grandolfi K, Sosciarelli V, Polito M. Resistance Training and the Effect of Load Blinding in Multiple Repetition Maximum Tests. Int J Sports Physiol Perform 2020; 15:441-443. [PMID: 31605521 DOI: 10.1123/ijspp.2018-0847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 03/20/2019] [Accepted: 06/11/2019] [Indexed: 10/27/2023]
Abstract
PURPOSE To compare performance in successive 1-repetition maximum (1RM) tests with the load known or unknown. METHODS Thirty-two resistance-trained men were randomly divided into 2 groups: load blinding (BLI; n = 16; age 28.1 [6.9] y, body mass 83.1 [11.5] kg, height 175.3 [5.8] cm) and load nonblinding (nBLI; n = 16; age 27.7 [4.1] y, body mass 83.2 [12.8] kg, height 178.7 [7.3] cm). The groups performed a 1RM test during 4 days (with an interval of 24-48 h) in the horizontal bench press with free weight. RESULTS In the BLI, there were no significant changes throughout the tests, with a difference of 1.6% between the first and fourth 1RM tests. In the nBLI, there was a significant interaction with time, and the values of the second (P = .03), third (P = .02), and fourth (P = .01) tests were higher than the first test; in addition, the fourth test was significantly higher than the second test (P = .02). The percentage difference between the last and first 1RM tests was 7.1%. The comparison between the groups demonstrated differences in the third (P = .04) and fourth (P = .02) tests with higher values in the nBLI. The intraclass correlation coefficient between the first and fourth 1RM tests was .93 for the BLI and .91 for the nBLI. CONCLUSION BLI does not influence 1RM testing in the bench press exercise.
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Nuzzo JL, Taylor JL, Gandevia SC. CORP: Measurement of upper and lower limb muscle strength and voluntary activation. J Appl Physiol (1985) 2019; 126:513-543. [DOI: 10.1152/japplphysiol.00569.2018] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Muscle strength, the maximal force-generating capacity of a muscle or group of muscles, is regularly assessed in physiological experiments and clinical trials. An understanding of the expected variation in strength and the factors that contribute to this variation is important when designing experiments, describing methodologies, interpreting results, and attempting to replicate methods of others and reproduce their findings. In this review (Cores of Reproducibility in Physiology), we report on the intra- and inter-rater reliability of tests of upper and lower limb muscle strength and voluntary activation in humans. Isometric, isokinetic, and isoinertial strength exhibit good intra-rater reliability in most samples (correlation coefficients ≥0.90). However, some tests of isoinertial strength exhibit systematic bias that is not resolved by familiarization. With the exception of grip strength, few attempts have been made to examine inter-rater reliability of tests of muscle strength. The acute factors most likely to affect muscle strength and serve as a source of its variation from trial-to-trial or day-to-day include attentional focus, breathing technique, remote muscle contractions, rest periods, temperature (core, muscle), time of day, visual feedback, body and limb posture, body stabilization, acute caffeine consumption, dehydration, pain, fatigue from preceding exercise, and static stretching >60 s. Voluntary activation, the nervous system’s ability to drive a muscle to create its maximal force, exhibits good intra-rater reliability when examined with twitch interpolation (correlation coefficients >0.80). However, inter-rater reliability has not been formally examined. The methodological factors most likely to influence voluntary activation are myograph compliance and sensitivity; stimulation location, intensity, and inadvertent stimulation of antagonists; joint angle (muscle length); and the resting twitch.
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Affiliation(s)
- James L. Nuzzo
- Neuroscience Research Australia, Randwick, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Sydney, Australia
| | - Janet L. Taylor
- Neuroscience Research Australia, Randwick, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Sydney, Australia
- School of Medical and Health Sciences, Edith Cowan University, Perth, Western Australia, Australia
| | - Simon C. Gandevia
- Neuroscience Research Australia, Randwick, New South Wales, Australia
- Prince of Wales Hospital Clinical School, University of New South Wales, Sydney, Australia
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Sabour S, Dastjerdi EV, Moezizadeh M. Effect of Training Status on Reliability of 1RM Testing in Women, Methodological Mistake. J Strength Cond Res 2016; 30:e7. [DOI: 10.1519/jsc.0b013e31828d1739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Comfort P, McMahon JJ. Reliability of Maximal Back Squat and Power Clean Performances in Inexperienced Athletes. J Strength Cond Res 2016; 29:3089-96. [PMID: 25559912 DOI: 10.1519/jsc.0000000000000815] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The aim of the study was to determine between-session reliability of maximal weight lifted during the back squat and power clean, in inexperienced athletes, and to identify the smallest detectable difference between sessions. Forty-four collegiate athletes (men: n = 32; age: 21.5 ± 2.0 years; height: 180.0 ± 6.1 cm; body mass: 81.01 ± 7.42 kg; women: n = 12; age: 21.0 ± 1.9 years; height: 169.0 ± 5.2 cm; body mass: 62.90 ± 7.46 kg) participated in this study. One repetition maximum (1RM) back squat and power cleans were each performed twice on separate days, 3-5 days apart. Paired samples' t tests revealed no significant differences between trial 1 and trial 2 of the power clean (70.55 ± 24.24 kg, 71.22 ± 23.87 kg, p > 0.05, power = 0.99) and the back squat (130.32 ± 34.05 kg, 129.82 ± 34.07 kg, p > 0.05, power = 1.0). No differences in reliability or measurement error were observed between men and women. Intraclass correlation coefficients (ICCs) demonstrated a high reliability (ICC = 0.997, p < 0.001) for between-session 1RM power clean with an R of 0.987; similarly, high reliability was observed for between-session back squat performances (ICC = 0.994, p < 0.001), with an R of 0.978. The smallest detectable difference between sessions for both measures were ∼5%, highlighting that coaches and researchers should look for a change of >5% to identify a meaningful change in both maximal back squat and power clean performance.
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Affiliation(s)
- Paul Comfort
- Human Performance Laboratory, Directorate of Sport, Exercise and Physiotherapy, University of Salford, Greater Manchester, United Kingdom
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Gerodimos V, Karatrantou K, Paschalis V, Zafeiridis A, Katsareli E, Bilios P, Kellis S. Reliability of concentric and eccentric strength of hip abductor and adductor muscles in young soccer players. Biol Sport 2015; 32:351-356. [PMID: 28479666 PMCID: PMC5394850 DOI: 10.5604/20831862.1189202] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 02/06/2015] [Accepted: 02/27/2015] [Indexed: 11/21/2022] Open
Abstract
The concentric and eccentric strength profile and muscular balance of the hip joint are important parameters for success in soccer. This study evaluated the reliability for the assessment of hip abduction and adduction isokinetic strength over a range of angular velocities (30 and 90°/s) and types of muscular actions (concentric and eccentric) in young soccer players. The reliability for the assessment of reciprocal (conventional and functional) and bilateral torque ratios was also examined. Fifteen male soccer players (15±1 years) performed two sessions, separated by three days. The testing protocol consisted of five maximal concentric and eccentric hip abductions and adductions of both legs at angular velocities of 30°/s and 90°/s. The peak torque was evaluated in young soccer players using an isokinetic dynamometer (Cybex Norm), and the reciprocal strength ratios (conventional and functional) and bilateral ratios (non-preferred to preferred leg ratios) were calculated. The test-retest reliability for the assessment of peak torque (ICC = 0.71-0.92) and of reciprocal muscle group ratios (ICC = 0.44-0.87) was found to be moderate to high. Bilateral torque ratios exhibited low to moderate reliability (ICC = 0.11-0.64). In conclusion, isokinetic strength of hip abductor and adductor muscles and the conventional and functional strength ratios can be reliably assessed in young soccer players, especially at low angular velocities. The assessment, however, of bilateral strength ratios for hip abductor/adductor muscles should be interpreted with more caution.
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Affiliation(s)
- V Gerodimos
- Department of Physical Education and Sport Sciences, University of Thessaly, Trikala, Greece
| | - K Karatrantou
- Department of Physical Education and Sport Sciences, University of Thessaly, Trikala, Greece
| | - V Paschalis
- Department of Physical Education and Sport Sciences, University of Thessaly, Trikala, Greece
| | - A Zafeiridis
- Department of Physical Education and Sport Sciences at Serres, Aristotle University of Thessaloniki, Greece
| | - E Katsareli
- Department of Physical Education and Sport Sciences, Aristotle University of Thessaloniki, Greece
| | - P Bilios
- Department of Physical Education and Sport Sciences, University of Thessaly, Trikala, Greece
| | - S Kellis
- Department of Physical Education and Sport Sciences, Aristotle University of Thessaloniki, Greece
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Bianco A, Filingeri D, Paoli A, Palma A. One repetition maximum bench press performance: A new approach for its evaluation in inexperienced males and females: A pilot study. J Bodyw Mov Ther 2015; 19:362-9. [DOI: 10.1016/j.jbmt.2014.11.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 11/25/2014] [Accepted: 11/26/2014] [Indexed: 01/15/2023]
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