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Baron M, Divernois G, Grandjean B, Guex K. Validity and Reliability of Handheld Dynamometry to Assess Isometric Hamstrings and Quadriceps Strength at Varying Muscle Lengths. J Sport Rehabil 2024; 33:267-274. [PMID: 38560999 DOI: 10.1123/jsr.2023-0256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 01/11/2024] [Accepted: 02/10/2024] [Indexed: 04/04/2024]
Abstract
CONTEXT The hamstrings are the most commonly injured muscle in sports and are especially injury prone in lengthened positions. Measuring knee muscle strength in such positions could be relevant to establish injury risk. Handheld dynamometry has been shown to be a valid, reliable, and practical tool to measure isometric muscle strength clinically. The aim of this study was to assess the validity and reliability of the assessment of isometric knee muscle strength with a handheld dynamometer (HHD) at various muscle lengths, by modifying the hip and knee angles during testing. DESIGN Concurrent validity and test-retest reliability. METHODS Thirty young healthy participants were recruited. Hamstring and quadriceps isometric strength was measured with a HHD and with an isokinetic dynamometer, over 2 testing sessions, in a randomized order. Isometric strength was measured on the right lower limb in 6 different positions, with the hip at either 0° or 80° of flexion and the knee at either 30°, 60°, or 90° of flexion. Pearson and Spearman correlations were used to assess the validity, and intraclass correlation coefficients were calculated to establish the test-retest reliability of the HHD. RESULTS Good to excellent reliability and moderate to high validity were found in all the tested muscle length positions, except for the hamstrings in a seated position with the knee extended at 30°. CONCLUSIONS The use of a HHD is supported in the clinical setting to measure knee muscle strength at varying muscle lengths in healthy adults, but not for the hamstrings in a lengthened position (hip flexed and knee extended). These results will have to be confirmed in sport-specific populations.
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Affiliation(s)
- Margaux Baron
- School of Health Sciences (HESAV), HES-SO University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland
| | - Gilles Divernois
- School of Health Sciences (HESAV), HES-SO University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland
| | - Benoît Grandjean
- School of Health Sciences (HESAV), HES-SO University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland
| | - Kenny Guex
- School of Health Sciences (HESAV), HES-SO University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland
- Swiss Athletics, Haus des Sports, Ittigen,Switzerland
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2
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Prince C, Guex K, Lachaux-Couttet G, Samozino P, Edouard P. Current warm-up practices before maximal sprinting in track-and-field (athletics). J Sports Med Phys Fitness 2024; 64:319-327. [PMID: 37955929 DOI: 10.23736/s0022-4707.23.15243-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2023]
Abstract
BACKGROUND Warm-up is commonly performed by track-and-field athletes before performing maximal sprinting activities. Whilst some warm-up strategies may enhance athletes' physical and mental readiness, less is known about the current athletes' behaviors and warm-up practices in track and field. Therefore, this study aimed to identify the warm-up practices in a population of athletes performing in sprinting disciplines. METHODS A cross-sectional exploratory study was performed in which track-and-field athletes, performing in athletics at a competitive level in disciplines requiring maximal acceleration and sprinting were recruited. We collected, using an online survey, information about 1) "General and Anthropometric data;" 2) "Athletics training practices" questioning the level of practices and the training frequency; and 3) "Athletics warm-up practices before maximal sprinting" questioning warm-up structure, duration and specific content. RESULTS A total of 114 athletes replied to the survey. They reported a mean weekly training duration of 10.5 (±4.0) hours and a pre-maximal sprint warm-up duration of 40.5 (±13.5) minutes. During warm-up, they were engaged in five principal activities: predominantly moderate jogging (95% participation, 8±3.3 minutes), succeeded by dynamic and/or ballistic stretching (78% participation, 9±4.3 minutes), followed by athletic drills (96% participation, 15±5.4 minutes), culminating in accelerations (100% participation) along with high-speed running (77% participation). Warm-up duration and composition differed across athletes' levels of practice and disciplines. CONCLUSIONS Most of the participants' warm-up practices were typically structured in a three-phase manner, comprising jogging, stretching, and specific training (athletic drills and accelerations). Most athletes followed scientific-based warm-up recommendations there are some areas where the evidence is limited, and more research is needed to determine the optimal warm-up routine for athletes.
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Affiliation(s)
- Caroline Prince
- Université Savoie Mont Blanc, Laboratoire Interuniversitaire de Biologie de la Motricité, Chambéry, France -
- Physiotherapy Department and Motion Analysis Lab, Swiss Olympic Medical Center, La Tour Hospital, Meyrin, Switzerland -
- Société Française des Masseurs Kinésithérapeute du Sport, SFMKS-Lab, Pierrefitte-sur-Seine, France -
| | - Kenny Guex
- School of Health Sciences (HESAV), HES-SO University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland
- Department of Sprints, Hurdles and Relays, Swiss Athletics, Haus des Sports, Ittigen, Switzerland
| | - Guillaume Lachaux-Couttet
- Physiotherapy Department and Motion Analysis Lab, Swiss Olympic Medical Center, La Tour Hospital, Meyrin, Switzerland
| | - Pierre Samozino
- Université Savoie Mont Blanc, Laboratoire Interuniversitaire de Biologie de la Motricité, Chambéry, France
| | - Pascal Edouard
- UJM-Saint-Etienne, Inter-university Laboratory of Human Movement Biology, Saint-Etienne, France
- Unit of Sports Medicine, Department of Clinical and Exercise Physiology, University Hospital of Saint-Etienne, Faculty of Medicine, Saint-Etienne, France
- European Athletics Medical and Anti-Doping Commission, European Athletics Association (EAA), Lausanne, Switzerland
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3
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Edouard P, Dandrieux PE, Junge A, Navarro L, Giroux C, Guex K, Branco P, Guilhem G, Hollander K. Is the risk of muscle injuries higher in the finals than in previous rounds of the 100 m, 200 m and 400 m sprints of international athletics championships? J Sci Med Sport 2024:S1440-2440(24)00055-0. [PMID: 38429218 DOI: 10.1016/j.jsams.2024.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 12/05/2023] [Accepted: 02/19/2024] [Indexed: 03/03/2024]
Abstract
OBJECTIVES To compare incidence rates of lower limb muscle injuries (LLMIs) and hamstring muscle injuries (HMIs) in 100 m, 200 m and 400 m sprints disciplines between finals, semi-finals and heats of international athletics championships. DESIGN Prospective total population study. METHODS We analysed in-competition LLMIs and HMIs of female and male athletes during eight championships between 2009 and 2022. RESULTS LLMI and HMI incidence rates in 100 m finals were significantly higher than in heats and semi-finals for female and male athletes. HMI incidence rates were significantly higher in 200 m finals than heats and semi-finals for male athletes. CONCLUSIONS LLMI and HMI risk was higher in finals compared to previous rounds during international athletics championships.
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Affiliation(s)
- Pascal Edouard
- Inter-university Laboratory of Human Movement Science (LIBM EA 7424), University Jean Monnet Saint-Etienne, Lyon 1, University Savoie Mont-Blanc, France; Department of Clinical and Exercise Physiology, Sports Medicine Unit, University Hospital of Saint-Etienne, Faculty of Medicine, France; European Athletics Medical & Anti Doping Commission, European Athletics Association (EAA), Switzerland.
| | - Pierre-Eddy Dandrieux
- Inter-university Laboratory of Human Movement Science (LIBM EA 7424), University Jean Monnet Saint-Etienne, Lyon 1, University Savoie Mont-Blanc, France; Mines Saint-Etienne, Univ Lyon, Univ Jean Monnet, INSERM, U 1059 Sainbiose, Centre CIS, France; Institute of Interdisciplinary Exercise Science and Sports Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Astrid Junge
- Institute of Interdisciplinary Exercise Science and Sports Medicine, MSH Medical School Hamburg, Hamburg, Germany; Center for Health in Performing Arts, MSH Medical School Hamburg, Hamburg, Germany
| | - Laurent Navarro
- Mines Saint-Etienne, Univ Lyon, Univ Jean Monnet, INSERM, U 1059 Sainbiose, Centre CIS, France
| | - Caroline Giroux
- French Institute of Sport (INSEP), Laboratory Sport, Expertise and Performance (EA 7370), France
| | - Kenny Guex
- School of Health Sciences (HESAV), HES-SO University of Applied Sciences and Arts Western Switzerland, Switzerland; Department of Sprints, Hurdles and Relays, Swiss Athletics, Haus des Sports, Switzerland
| | - Pedro Branco
- European Athletics Medical & Anti Doping Commission, European Athletics Association (EAA), Switzerland
| | - Gaël Guilhem
- French Institute of Sport (INSEP), Laboratory Sport, Expertise and Performance (EA 7370), France
| | - Karsten Hollander
- Institute of Interdisciplinary Exercise Science and Sports Medicine, MSH Medical School Hamburg, Hamburg, Germany
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Edouard P, Svensson F, Guex K. A call to change our vision on sports injuries and their prevention: adopt a salutogenic approach! See the half-full glass! BMJ Open Sport Exerc Med 2023; 9:e001793. [PMID: 37953971 PMCID: PMC10632886 DOI: 10.1136/bmjsem-2023-001793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/31/2023] [Indexed: 11/14/2023] Open
Affiliation(s)
- Pascal Edouard
- Inter-university Laboratory of Human Movement Biology (EA 7424), University Jean Monnet Saint-Etienne, Lyon 1, University Savoie Mont-Blanc, Saint-Etienne, France
- Department of Clinical and Exercise Physiology, Sports Medicine Unit, University Hospital of Saint-Etienne, Faculty of Medicine, Saint-Etienne, France
| | | | - Kenny Guex
- Haute Ecole de Santé Vaud (HESAV), filière physiothérapie, HES-SO Haute Ecole Spécialisée de Suisse occidentale, Lausanne, Switzerland
- Département Sprint/Haies/Relais, Haus des Sports, Swiss Athletics, Ittigen, Switzerland
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Edouard P, Mendiguchia J, Guex K, Lahti J, Prince C, Samozino P, Morin JB. Sprinting: a key piece of the hamstring injury risk management puzzle. Br J Sports Med 2023; 57:4-6. [PMID: 35927000 DOI: 10.1136/bjsports-2022-105532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/16/2022] [Indexed: 01/06/2023]
Affiliation(s)
- Pascal Edouard
- Inter-University Laboratory of Human Movement Biology, Univ Lyon, UJM-Saint-Etienne, Saint-Etienne, France .,Department of Clinical and Exercise Physiology, Sports Medicine Unit, University Hospital of Saint-Etienne, Saint-Etienne, France
| | - Jurdan Mendiguchia
- Department of Physical Therapy, ZENTRUM Rehab and Performance Center, Barañain, Spain
| | - Kenny Guex
- School of Health Sciences (HESAV), HES-SO University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland.,Swiss Athletics, Haus des Sports, Ittigen, Switzerland
| | - Johan Lahti
- LAMHESS, Université Côte d'Azur, Nice, France
| | - Caroline Prince
- Inter-university Laboratory of Human Movement Biology, EA 7424, Univ Savoie Mont Blanc, Chambéry, France.,Physiotherapy department and motion analysis lab, Swiss Olympic Medical Center, La Tour Hospital, Meyrin, Switzerland
| | - Pierre Samozino
- Inter-university Laboratory of Human Movement Biology, EA 7424, Univ Savoie Mont Blanc, Chambéry, France
| | - Jean-Benoît Morin
- Inter-University Laboratory of Human Movement Biology, Univ Lyon, UJM-Saint-Etienne, Saint-Etienne, France.,Sports Performance Research Institute New Zealand, School of Sport and Recreation, Auckland University of Technology, Auckland, New Zealand
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Edouard P, Pollock N, Guex K, Kelly S, Prince C, Navarro L, Branco P, Depiesse F, Gremeaux V, Hollander K. Hamstring Muscle Injuries and Hamstring Specific Training in Elite Athletics (Track and Field) Athletes. Int J Environ Res Public Health 2022; 19:10992. [PMID: 36078705 PMCID: PMC9518337 DOI: 10.3390/ijerph191710992] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 08/30/2022] [Accepted: 08/30/2022] [Indexed: 06/15/2023]
Abstract
OBJECTIVE We aimed to describe hamstring muscle injury (HMI) history and hamstring specific training (HST) in elite athletes. A secondary aim was to analyse the potential factors associated with in-championships HMI. METHODS We conducted a prospective cohort study to collect data before and during the 2018 European Athletics Championships. Injury and illness complaints during the month before the championship, HMI history during the entire career and the 2017-18 season, HST (strengthening, stretching, core stability, sprinting), and in-championship HMI were recorded. We calculated proportions of athletes with HMI history, we compared HST according to sex and disciplines with Chi2 tests or ANOVA, and analysed factors associated with in-championship HMI using simple model logistic regression. RESULTS Among the 357 included athletes, 48% reported at least one HMI during their career and 24% during the 2017-18 season. Of this latter group, 30.6% reported reduced or no participation in athletics' training or competition at the start of the championship due to the hamstring injury. For HST, higher volumes of hamstring stretching and sprinting were reported for disciplines requiring higher running velocities (i.e., sprints, hurdles, jumps, combined events and middle distances). Five in-championship HMIs were recorded. The simple model analysis showed a lower risk of sustaining an in-championships HMI for athletes who performed more core (lumbo-pelvic) stability training (OR = 0.49 (95% CI: 0.25 to 0.89), p = 0.021). CONCLUSIONS Our present study reports that HMI is a characteristic of the athletics athletes' career, especially in disciplines involving sprinting. In these disciplines, athletes were performing higher volumes of hamstring stretching and sprinting than in other disciplines. Further studies should be conducted to better understand if and how HST are protective approaches for HMI in order to improve HMI risk reduction strategies.
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Affiliation(s)
- Pascal Edouard
- Inter-University Laboratory of Human Movement Biology (LIBM EA 7424), University of Lyon, University Jean Monnet, 42023 Saint Etienne, France
- Department of Clinical and Exercise Physiology, Sports Medicine Unit, Faculty of Medicine, University Hospital of Saint-Etienne, 42055 Saint-Etienne, France
- European Athletics Medical & Anti-Doping Commission, European Athletics Association (EAA), 1007 Lausanne, Switzerland
| | - Noel Pollock
- Institute of Sport, Exercise and Health, University College London, London W1T 7HA, UK
- National Performance Institute, British Athletics, Loughborough LE11 3TU, UK
| | - Kenny Guex
- School of Health Sciences (HESAV), HES-SO University of Applied Sciences and Arts Western Switzerland, 1011 Lausanne, Switzerland
- Department of Sprints, Hurdles and Relays, Swiss Athletics, Haus des Sports, 3063 Ittigen, Switzerland
| | - Shane Kelly
- National Performance Institute, British Athletics, Loughborough LE11 3TU, UK
- Ballet Healthcare, The Royal Ballet, London WC2E 9DA, UK
| | - Caroline Prince
- Laboratoire Interuniversitaire de Biologie de la Motricité, Université Savoie Mont Blanc, EA 7424, 73000 Chambéry, France
- Physiotherapy Department and Motion Analysis Lab, Swiss Olympic Medical Center, La Tour Hospital, 1217 Meyrin, Switzerland
- Société Française des Masseurs Kinésithérapeute du Sport, SFMKS-Lab, 93380 Pierrefitte-sur-Seine, France
| | - Laurent Navarro
- Mines Saint-Etienne, U1059 Sainbiose, INSERM, Centre CIS, University Lyon, University Jean Monnet, 42023 Saint-Etienne, France
| | - Pedro Branco
- European Athletics Medical & Anti-Doping Commission, European Athletics Association (EAA), 1007 Lausanne, Switzerland
| | - Frédéric Depiesse
- CH Chalons en Champagne et Institut Mutualiste de Montsouris, 75014 Paris, France
| | - Vincent Gremeaux
- Swiss Olympic Medical Center, Centre de Médecine du Sport, Division de Médecine Physique et Réadaptation, Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, Switzerland
- Institute of Sport Sciences, University of Lausanne, 1015 Lausanne, Switzerland
| | - Karsten Hollander
- Institute of Interdisciplinary Exercise Science and Sports Medicine, MSH Medical School Hamburg, 20457 Hamburg, Germany
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Citherlet T, Crettaz von Roten F, Kayser B, Guex K. Acute Effects of the Wim Hof Breathing Method on Repeated Sprint Ability: A Pilot Study. Front Sports Act Living 2021; 3:700757. [PMID: 34514386 PMCID: PMC8424088 DOI: 10.3389/fspor.2021.700757] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 07/02/2021] [Indexed: 11/23/2022] Open
Abstract
The Wim Hof breathing method (WHBM) combines periods of hyperventilation (HV) followed by voluntary breath-holds (BH) at low lung volume. It has been increasingly adopted by coaches and their athletes to improve performance, but there was no published research on its effects. We determined the feasibility of implementing a single WHBM session before repeated sprinting performance and evaluated any acute ergogenic effects. Fifteen amateur runners performed a single WHBM session prior to a Repeated Ability Sprint Test (RAST) in comparison to voluntary HV or spontaneous breathing (SB) (control) in a randomized cross-over design. Gas exchange, heart rate, and finger pulse oxygen saturation (SpO2) were monitored. Despite large physiological effects in the SpO2 and expired carbon dioxide (VCO2) levels of both HV and WHBM, no significant positive or negative condition effects were found on RAST peak power, average power, or fatigue index. Finger SpO2 dropped to 60 ± 12% at the end of the BHs. Upon the last HV in the WHBM and HV conditions, end-tidal CO2 partial pressure (PETCO2) values were 19 ± 3 and 17 ± 3 mmHg, indicative of respiratory alkalosis with estimated arterial pH increases of +0.171 and of +0.181, respectively. Upon completion of RAST, 8 min cumulated expired carbon dioxide volumes in the WHBM and HV were greater than in SB, suggesting lingering carbon dioxide stores depletion. These findings indicate that despite large physiological effects, a single WHBM session does not improve anaerobic performance in repeated sprinting exercise.
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Affiliation(s)
- Tom Citherlet
- Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | | | - Bengt Kayser
- Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Kenny Guex
- School of Health Sciences, University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland
- Swiss Athletics, Haus des Sports, Ittigen, Switzerland
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Edouard P, Lahti J, Nagahara R, Samozino P, Navarro L, Guex K, Rossi J, Brughelli M, Mendiguchia J, Morin JB. Low Horizontal Force Production Capacity during Sprinting as a Potential Risk Factor of Hamstring Injury in Football. Int J Environ Res Public Health 2021; 18:ijerph18157827. [PMID: 34360125 PMCID: PMC8345704 DOI: 10.3390/ijerph18157827] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 06/18/2021] [Accepted: 07/06/2021] [Indexed: 01/09/2023]
Abstract
Clear decreases in horizontal force production capacity during sprint acceleration have been reported after hamstring injuries (HI) in football players. We hypothesized that lower FH0 is associated with a higher HI occurrence in football players. We aimed to analyze the association between sprint running horizontal force production capacities at low (FH0) and high (V0) velocities, and HI occurrence in football. This prospective cohort study included 284 football players over one season. All players performed 30 m field sprints at the beginning and different times during the season. Sprint velocity data were used to compute sprint mechanical properties. Players' injury data were prospectively collected during the entire season. Cox regression analyses were performed using new HI as the outcome, and horizontal force production capacity (FH0 and V0) was used at the start of the season (model 1) and at each measurement time point within the season (model 2) as explanatory variables, adjusted for individual players' (model 2) age, geographical group of players, height, body mass, and previous HI, with cumulative hours of football practice as the time scale. A total of 47 new HI (20% of all injuries) were observed in 38 out of 284 players (13%). There were no associations between FH0 and/or V0 values at the start of the season and new HI occurrence during the season (model 1). During the season, a total of 801 measurements were performed, from one to six per player. Lower measured FH0 values were significantly associated with a higher risk of sustaining HI within the weeks following sprint measurement (HR = 2.67 (95% CI: 1.51 to 4.73), p < 0.001) (model 2). In conclusion, low horizontal force production capacities at low velocity during early sprint acceleration (FH0) may be considered as a potential additional factor associated with HI risk in a comprehensive, multifactorial, and individualized approach.
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Affiliation(s)
- Pascal Edouard
- UJM-Saint-Etienne, Laboratory Interuniversity of Human Movement Sciences, University Lyon, EA 7424, F-42023 Saint-Etienne, France; (J.R.); (J.-B.M.)
- Sports Medicine Unity, Department of Clinical and Exercise Physiology, Faculty of Medicine, University Hospital of Saint-Etienne, CEDEX 2, F-42055 Saint-Etienne, France
- Correspondence: ; Tel.: +33-674-574-691
| | - Johan Lahti
- LAMHESS, Université Côte d’Azur, F-06200 Nice, France;
| | - Ryu Nagahara
- Sports Research and Development Core, University of Tsukuba, Ibaraki 305-8574, Japan;
- Faculty of Sports and Budo Coaching Studies, National Institute of Fitness and Sports in Kanoya, Kagoshima 891-2393, Japan
| | - Pierre Samozino
- Laboratory Interuniversity of Human Movement Sciences, University Savoie Mont Blanc, EA 7424, F-73000 Chambéry, France;
| | - Laurent Navarro
- Mines Saint-Etienne, Centre CIS, Université de Lyon, Université Jean Monnet, INSERM, U 1059 Sainbiose, F-42023 Saint-Etienne, France;
| | - Kenny Guex
- School of Health Sciences (HESAV), HES-SO University of Applied Sciences and Arts Western Switzerland, 1011 Lausanne, Switzerland;
- Department of Sprints, Hurdles and Relays, Swiss Athletics, Haus des Sports, 3063 Ittigen, Switzerland
| | - Jérémy Rossi
- UJM-Saint-Etienne, Laboratory Interuniversity of Human Movement Sciences, University Lyon, EA 7424, F-42023 Saint-Etienne, France; (J.R.); (J.-B.M.)
| | - Matt Brughelli
- Sports Performance Research Institute New Zealand, Auckland University of Technology, 1010 Auckland, New Zealand;
| | - Jurdan Mendiguchia
- Department of Physical Therapy, Zentrum Rehabilitation and Performance Center, 31002 Pamplona, Spain;
| | - Jean-Benoît Morin
- UJM-Saint-Etienne, Laboratory Interuniversity of Human Movement Sciences, University Lyon, EA 7424, F-42023 Saint-Etienne, France; (J.R.); (J.-B.M.)
- LAMHESS, Université Côte d’Azur, F-06200 Nice, France;
- Sports Performance Research Institute New Zealand, Auckland University of Technology, 1010 Auckland, New Zealand;
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Prince C, Morin JB, Mendiguchia J, Lahti J, Guex K, Edouard P, Samozino P. Sprint Specificity of Isolated Hamstring-Strengthening Exercises in Terms of Muscle Activity and Force Production. Front Sports Act Living 2021; 2:609636. [PMID: 33554110 PMCID: PMC7859261 DOI: 10.3389/fspor.2020.609636] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 12/01/2020] [Indexed: 11/30/2022] Open
Abstract
To train hamstring muscle specifically to sprint, strengthening programs should target exercises associated with horizontal force production and high levels of hamstring activity. Therefore, the objectives of this study were to analyze the correlation between force production capacities during sprinting and hamstring strengthening exercises, and to compare hamstring muscle activity during sprinting and these exercises. Fourteen track and field regional level athletes performed two maximal 50-m sprints and six strengthening exercises: Nordic hamstring exercises without and with hip flexion, Upright-hip-extension in isometric and concentric modalities, Standing kick, and Slide-leg-bridge. The sprinting horizontal force production capacity at low (F0) and high (V0) speeds was computed from running velocity data. Hamstring muscle performances were assessed directly or indirectly during isolated exercises. Hamstring muscle electromyographic activity was recorded during all tasks. Our results demonstrate substantially large to very large correlations between V0 and performances in the Upright-hip-extension in isometric (rs = 0.56; p = 0.040), Nordic hamstring exercise without hip flexion (rs = 0.66; p = 0.012) and with 90° hip flexion (rs = 0.73; p = 0.003), and between F0 and Upright-hip-extension in isometric (rs = 0.60; p = 0.028) and the Nordic hamstring exercise without hip flexion (rs = 0.59; p = 0.030). However, none of the test exercises activated hamstring muscles more than an average of 60% of the maximal activation during top-speed sprinting. In conclusion, training programs aiming to be sprint-specific in terms of horizontal force production could include exercises such as the Upright-hip-extension and the Nordic hamstring exercise, in addition to maximal sprinting activity, which is the only exercise leading to high levels of hamstring muscle activity.
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Affiliation(s)
- Caroline Prince
- University of Savoie Mont Blanc, Laboratoire Interuniversitaire de Biologie de la Motricité (EA7424), Chambéry, France.,Physiotherapy and Sports Medicine Department, Swiss Olympic Medical Center, La Tour Hospital, Meyrin, Switzerland
| | - Jean-Benoît Morin
- University of Lyon, UJM-Saint-Etienne, Inter-university Laboratory of Human Movement Science (LIBM EA 7424), Saint-Étienne, France.,Sports Performance Research Institute New Zealand, School of Sport and Recreation, Auckland University of Technology, Auckland, New Zealand
| | - Jurdan Mendiguchia
- Department of Physical Therapy, ZENTRUM Rehab and Performance Center, Barañain, Spain
| | - Johan Lahti
- University of Côte d'Azur, LAMHESS, Nice, France
| | - Kenny Guex
- School of Health Sciences (HESAV), University of Applied Sciences and Arts Western Switzerland (HES-SO), Lausanne, Switzerland.,Head Coach Sprint/Hurdles/Relays Coach 400m/400m Hurdles Swiss Athletics, Haus des Sports, Ittigen, Switzerland
| | - Pascal Edouard
- University of Lyon, UJM-Saint-Etienne, Inter-university Laboratory of Human Movement Science (LIBM EA 7424), Saint-Étienne, France.,Sports Medicine Unit, Department of Clinical and Exercise Physiology, Faculty of Medicine, Regional Institute of Medicine and Sports Engineering (IRMIS), University Hospital of Saint-Etienne, Saint-Ètienne, France
| | - Pierre Samozino
- University of Savoie Mont Blanc, Laboratoire Interuniversitaire de Biologie de la Motricité (EA7424), Chambéry, France
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Guex K, Serain E, Gremion G, Besson C, Faiss R, Majo J, Degache F. Participating In The Race Across AMerica In A Team Of Eight Cyclists: Do Not Neglect Crew Preparation. Open Access J Sports Med 2019; 10:161-169. [PMID: 31807092 PMCID: PMC6839592 DOI: 10.2147/oajsm.s219124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 09/28/2019] [Indexed: 12/20/2022] Open
Abstract
Background The Race Across AMerica (RAAM) is considered as one of the longest, and most difficult cycling races in the world. It can be performed in solo or in relay of two, four or eight persons. Purpose/method The aim of the present study was to investigate several physiological, perceptual and psychological responses before, during and after RAAM in a team of eight amateur cyclists. Because logistics of all team is demanding and complex, crew members have followed the same testing procedure. Results The main result is that parameters were globally not altered to a greater extent in cyclists than in crew members over the course of the RAAM, and that all variables returned to pre-race levels 1 week after the end of the race in both groups. In crew, body fat was decreased (p < 0.05) at mid-race (Mid) vs 1 week before the RAAM (Pre) (−1.5%) and total body water was increased (p < 0.05) at Mid vs Pre (+2.5%). In pre-relay quadriceps strength in cyclists was significantly lower (p < 0.05) at Mid vs Pre (41.6 ± 9.1 vs 45.0 ± 11.2 N, d = 0.36). Therefore, performing the race with eight well-prepared amateur cyclists seems to decrease potential risks on health. In crew, quadriceps strength remained stable at each assessment time but general fatigue increased all along the race. Anger was increased (p < 0.05) at Mid vs Pre in crew. Conclusion The most important message of this study is that crew members for a team of eight require adequate and sufficient preparation and training. Roles and responsibilities need to be thoroughly defined; individuals need to know each other beforehand and they must be prepared for sleep deprivation. The results of this study show the importance of the preparation of two teams: crew members, as well as cyclists.
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Affiliation(s)
- Kenny Guex
- School of Health Sciences (HESAV), University of Applied Sciences and Arts Western Switzerland (HES-SO), Lausanne, Switzerland
| | - Emilie Serain
- School of Health Sciences (HESAV), University of Applied Sciences and Arts Western Switzerland (HES-SO), Lausanne, Switzerland
| | - Gerald Gremion
- Department of Sports Medicine, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Cyril Besson
- Department of Sports Medicine, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Raphael Faiss
- Institute of Sports Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Jocelyne Majo
- School of Management and Engineering Vaud (HEIG-VD), University of Applied Sciences and Arts Western Switzerland (HES-SO), Delémont, Switzerland
| | - Francis Degache
- School of Health Sciences (HESAV), University of Applied Sciences and Arts Western Switzerland (HES-SO), Lausanne, Switzerland.,Institute of Sports Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland.,Therapeutic and Performance Sports Institute, MotionLab, Lausanne, Switzerland
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Degache F, Serain E, Vernillo G, Meyer F, Falbriard M, Savoldelli A, Guex K, Millet GP. Postural Control Follows a Bi-Phasic Alteration Pattern During Mountain Ultra-Marathon. Front Physiol 2019; 9:1971. [PMID: 30713506 PMCID: PMC6346676 DOI: 10.3389/fphys.2018.01971] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 12/31/2018] [Indexed: 02/03/2023] Open
Abstract
It is well knows that postural control (PC) is deteriorated with neuromuscular fatigue, altitude or sleep deprivation induced by a mountain ultra-marathon (MUM). Several regulatory mechanisms have also been reported during this type of event and the changes in PC at different points of MUM remain unknown. The purpose of this study was to investigate the time course of PC during an extreme MUM. We tested the hypothesis that PC alteration would not increase linearly. Methods: 16 participants (age 45.1 ± 9.6 years) were tested bipedaly on a posturographic platform for 51.2 s with eyes open every ∼50 km. Both traditional and stabilogram diffusion analyses (SDA) were performed. A visual analog scale (VAS) was used for a subjective evaluation of global fatigue, sleep feeling and pain. Results: The main parameters (center of pressure trajectory analysis) increased significantly (p < 0.001, d = 1.56, very large) until km 100. This was confirmed by SDA in the antero-posterior plane. Short term effective diffusion coefficient significantly increased (p < 0.001, d = 1.07, very large) as critical point (p < 0.01, d = 1.57, very large). From km 100 to 200, a different response was observed with a continuous decrease in most of the PC parameters. This was confirmed by SDA in the antero-posterior plane. Short term effective diffusion coefficient significantly increased (p < 0.001, d = 1.39, very large) as critical point (p < 0.01, d = 1.51, very large). Conclusion: Posture alteration is progressively increased until 100 km. After this point, compensatory mechanisms appear to limit the posture degradation. This bi-phasic response is of interest for better understanding the coping with extreme fatigue.
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Affiliation(s)
- Francis Degache
- School of Health Sciences, University of Applied Science and Arts Western Switzerland, Lausanne, Switzerland
| | - Emilie Serain
- School of Health Sciences, University of Applied Science and Arts Western Switzerland, Lausanne, Switzerland
| | - Gianluca Vernillo
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,Research Center for Sport, Mountain and Health (CeRiSM), University of Verona, Rovereto, Italy
| | - Frederic Meyer
- Institute of Sports Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Mathieu Falbriard
- Laboratory of Movement Analysis and Measurement, STI, Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne, Switzerland
| | - Aldo Savoldelli
- Research Center for Sport, Mountain and Health (CeRiSM), University of Verona, Rovereto, Italy.,Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Kenny Guex
- School of Health Sciences, University of Applied Science and Arts Western Switzerland, Lausanne, Switzerland
| | - Grégoire P Millet
- Institute of Sports Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
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Edouard P, Guex K, Besson C, Mendiguchia J, Gremeaux V. [Hamstring injury prevention]. Rev Med Suisse 2018; 14:1354-1357. [PMID: 29998638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Hamstring muscle injury is the first diagnosis of injury in sports involving sprints. Its prevention represents a fundamental challenge for the technical and health professionals around the athletes. Risk factors have been described and can be used for screening at-risk individuals (age, history of hamstring injury, strength deficit). Although every determinant of the occurrence of these injuries has not yet been determined, and currently available preventive measures are not fully effective (eccentric muscle strengthening and strength deficit screening), these preventive measures do exist and must be implemented to the benefit of athletes before more comprehensive approaches are developed and demonstrate greater efficiency.
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Affiliation(s)
- Pascal Edouard
- Unité de médecine du sport, Service de physiologie clinique et de l'exercice, CHU de Saint-Etienne, 42055 Saint-Etienne, France
- Laboratoire de biologie de la motricité (EA 7424), Université de Lyon, Université Jean-Monnet, 42100 Saint-Etienne, France
- Commission médicale, Fédération française d'athlétisme, 75013 Paris, France
| | - Kenny Guex
- Filière physiothérapie, Haute école de santé Vaud (HESAV), Haute école spécialisée de Suisse Occidentale (HES-SO), 2800 Delémont
| | - Cyril Besson
- Swiss olympic medical center, Division de médecine physique et réadaptation, CHUV, 1011 Lausanne
| | - Jurdan Mendiguchia
- Department of Physical Therapy, Zentrum Rehab and Performance Center, 31010 Barañain, Espagne
| | - Vincent Gremeaux
- Swiss olympic medical center, Division de médecine physique et réadaptation, CHUV, 1011 Lausanne
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Guex K, Degache F, Morisod C, Sailly M, Millet GP. Hamstring Architectural and Functional Adaptations Following Long vs. Short Muscle Length Eccentric Training. Front Physiol 2016; 7:340. [PMID: 27536252 PMCID: PMC4971444 DOI: 10.3389/fphys.2016.00340] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 07/21/2016] [Indexed: 11/18/2022] Open
Abstract
Most common preventive eccentric-based exercises, such as Nordic hamstring do not include any hip flexion. So, the elongation stress reached is lower than during the late swing phase of sprinting. The aim of this study was to assess the evolution of hamstring architectural (fascicle length and pennation angle) and functional (concentric and eccentric optimum angles and concentric and eccentric peak torques) parameters following a 3-week eccentric resistance program performed at long (LML) vs. short muscle length (SML). Both groups performed eight sessions of 3–5 × 8 slow maximal eccentric knee extensions on an isokinetic dynamometer: the SML group at 0° and the LML group at 80° of hip flexion. Architectural parameters were measured using ultrasound imaging and functional parameters using the isokinetic dynamometer. The fascicle length increased by 4.9% (p < 0.01, medium effect size) in the SML and by 9.3% (p < 0.001, large effect size) in the LML group. The pennation angle did not change (p = 0.83) in the SML and tended to decrease by 0.7° (p = 0.09, small effect size) in the LML group. The concentric optimum angle tended to decrease by 8.8° (p = 0.09, medium effect size) in the SML and by 17.3° (p < 0.01, large effect size) in the LML group. The eccentric optimum angle did not change (p = 0.19, small effect size) in the SML and tended to decrease by 10.7° (p = 0.06, medium effect size) in the LML group. The concentric peak torque did not change in the SML (p = 0.37) and the LML (p = 0.23) groups, whereas eccentric peak torque increased by 12.9% (p < 0.01, small effect size) and 17.9% (p < 0.001, small effect size) in the SML and the LML group, respectively. No group-by-time interaction was found for any parameters. A correlation was found between the training-induced change in fascicle length and the change in concentric optimum angle (r = −0.57, p < 0.01). These results suggest that performing eccentric exercises lead to several architectural and functional adaptations. However, further investigations are required to confirm the hypothesis that performing eccentric exercises at LML may lead to greater adaptations than a similar training performed at SML.
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Affiliation(s)
- Kenny Guex
- Department of Physiotherapy, University of Health Sciences (Haute Ecole de Santé Vaud), University of Applied Sciences and Arts Western Switzerland (Haute École Spécialisée de Suisse Occidentale) Lausanne, Switzerland
| | - Francis Degache
- Department of Physiotherapy, University of Health Sciences (Haute Ecole de Santé Vaud), University of Applied Sciences and Arts Western Switzerland (Haute École Spécialisée de Suisse Occidentale) Lausanne, Switzerland
| | - Cynthia Morisod
- Department of Physiology, Faculty of Biology and Medicine, Institute of Sport Sciences, University of Lausanne Lausanne, Switzerland
| | | | - Gregoire P Millet
- Department of Physiology, Faculty of Biology and Medicine, Institute of Sport Sciences, University of Lausanne Lausanne, Switzerland
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Guex K. [Optimization of resistance training using elastic bands]. Rev Med Suisse 2015; 11:1434-1437. [PMID: 26398972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Resistance training using elastic bands allows to perform a large variety of exercises for upper and lower body. It can be considered as a real alternative to the use of fitness equipment or free weight. After having determined the goal of the resistance training (i.e., maximal strength, hypertrophy, power or local muscular endurance), the acute program variables (i.e., muscle action, loading, volume, exercise selection and order, rest periods and repetition velocity) must be selected regarding the recommendations for strength training. The load is the most important variable in resistance program design. To determine it in an accurate way, when using elastic bands, it is recommended to use the Multiple RM test.
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Degache F, Van Zaen J, Oehen L, Guex K, Trabucchi P, Millet G. Alterations in postural control during the world's most challenging mountain ultra-marathon. PLoS One 2014; 9:e84554. [PMID: 24465417 PMCID: PMC3897373 DOI: 10.1371/journal.pone.0084554] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 11/15/2013] [Indexed: 11/18/2022] Open
Abstract
We investigated postural control (PC) effects of a mountain ultra-marathon (MUM): a 330-km trail run with 24000 m of positive and negative change in elevation. PC was assessed prior to (PRE), during (MID) and after (POST) the MUM in experienced ultra-marathon runners (n = 18; finish time = 126 ± 16 h) and in a control group (n = 8) with a similar level of sleep deprivation. Subjects were instructed to stand upright on a posturographic platform over a period of 51.2 seconds using a double-leg stance under two test conditions: eyes open (EO) and eyes closed (EC). Traditional measures of postural stability (center of pressure trajectory analysis) and stabilogram-diffusion analysis (SDA) parameters were analysed. For the SDA, a significantly greater short-term effective diffusion was found at POST compared with PRE in the medio-lateral (ML; Dxs) and antero-posterior (AP) directions (Dys) in runners (p<0.05) The critical time interval (Ctx) in the ML direction was significantly higher at MID (p<0.001) and POST (p<0.05) than at PRE in runners. At MID (p<0.001) and POST (p<0.05), there was a significant difference between the two groups. The critical displacement (Cdx) in the ML was significantly higher at MID and at POST (p<0.001) compared with PRE for runners. A significant difference in Cdx was observed between groups in EO at MID (p<0.05) and POST (p<0.005) in the ML direction and in EC at POST in the ML and AP directions (p<0.05). Our findings revealed significant effects of fatigue on PC in runners, including, a significant increase in Ctx (critical time in ML plan) in EO and EC conditions. Thus, runners take longer to stabilise their body at POST than at MID. It is likely that the mountainous characteristics of MUM (unstable ground, primarily uphill/downhill running, and altitude) increase this fatigue, leading to difficulty in maintaining balance.
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Affiliation(s)
- Francis Degache
- School of Health Sciences, Health Research Unit, University of Applied Sciences Western Switzerland, Lausanne, Switzerland
| | - Jérôme Van Zaen
- Applied Signal Processing Group, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Lukas Oehen
- Institute of Sports Sciences, Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Kenny Guex
- School of Health Sciences, Department of Physiotherapy, University of Applied Sciences Western Switzerland, Lausanne, Switzerland
| | | | - Gégoire Millet
- Institute of Sports Sciences, Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
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Guex K, Degache F, Gremion G, Millet GP. Effect of hip flexion angle on hamstring optimum length after a single set of concentric contractions. J Sports Sci 2013; 31:1545-52. [DOI: 10.1080/02640414.2013.786186] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Abstract
CONTEXT Hamstrings strains are common and debilitating injuries in many sports. Most hamstrings exercises are performed at an inadequately low hip-flexion angle because this angle surpasses 70° at the end of the sprinting leg's swing phase, when most injuries occur. OBJECTIVE To evaluate the influence of various hip-flexion angles on peak torques of knee flexors in isometric, concentric, and eccentric contractions and on the hamstrings-to-quadriceps ratio. DESIGN Descriptive laboratory study. SETTING Research laboratory. PATIENTS AND OTHER PARTICIPANTS Ten national-level sprinters (5 men, 5 women; age = 21.2 ± 3.6 years, height = 175 ± 6 cm, mass = 63.8 ± 9.9 kg). INTERVENTION(S) For each hip position (0°, 30°, 60°, and 90° of flexion), participants used the right leg to perform (1) 5 seconds of maximal isometric hamstrings contraction at 45° of knee flexion, (2) 5 maximal concentric knee flexion-extensions at 60° per second, (3) 5 maximal eccentric knee flexion-extensions at 60° per second, and (4) 5 maximal eccentric knee flexionextensions at 150° per second. MAIN OUTCOME MEASURE(S) Hamstrings and quadriceps peak torque, hamstrings-to-quadriceps ratio, lateral and medial hamstrings root mean square. RESULTS We found no difference in quadriceps peak torque for any condition across all hip-flexion angles, whereas hamstrings peak torque was lower at 0° of hip flexion than at any other angle (P < .001) and greater at 90° of hip flexion than at 30° and 60° (P < .05), especially in eccentric conditions. As hip flexion increased, the hamstrings-to-quadriceps ratio increased. No difference in lateral or medial hamstrings root mean square was found for any condition across all hip-flexion angles (P > .05). CONCLUSIONS Hip-flexion angle influenced hamstrings peak torque in all muscular contraction types; as hip flexion increased, hamstrings peak torque increased. Researchers should investigate further whether an eccentric resistance training program at sprint-specific hip-flexion angles (70° to 80°) could help prevent hamstrings injuries in sprinters. Moreover, hamstrings-to-quadriceps ratio assessment should be standardized at 80° of hip flexion.
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Affiliation(s)
- Kenny Guex
- Department of Physiotherapy, School of Health Sciences, University of Applied Sciences Western Switzerland, Lausanne, Switzerland.
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Degache F, Guex K, Fourchet F, Morin JB, Millet GP, Tomazin K, Millet GY. Changes in running mechanics and spring-mass behaviour induced by a 5-hour hilly running bout. J Sports Sci 2013; 31:299-304. [DOI: 10.1080/02640414.2012.729136] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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