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Hamstring eccentrics

Justin W Y Lee, Cheng Li, Patrick S H Yung, Kai-Ming Chan
Background/Objective: Evaluating hamstring strength by isokinetic dynamometry is limited by various practical issues such as time and cost. A video-based Nordic hamstring exercise is introduced as an alternative option. The aims of this study are to evaluate 1.) the between-session reliability and 2.) concurrent validity of the testing method compared to a standardized isokinetic dynamometry. Methods: Thirty male elite footballers were recruited for the study. From the Nordic hamstring exercise, the video-analysis-determined Nordic break-point angles where the participant could no longer withstand the force of the fall (eccentric mode) and the number of seconds that the player could hold at 30° forward flexion angle (isometric mode) were measured...
June 2017: Journal of Exercise Science and Fitness
Arnhild Bakken, Stephen Targett, Tone Bere, Cristiano Eirale, Abdulaziz Farooq, Andrea B Mosler, Johannes L Tol, Rod Whiteley, Karim M Khan, Roald Bahr
BACKGROUND: Lower extremity muscle strength tests are commonly used to screen for injury risk in professional soccer. However, there is limited evidence on the ability of such tests in predicting future injuries. PURPOSE: To examine the association between hip and thigh muscle strength and the risk of lower extremity injuries in professional male soccer players. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Professional male soccer players from 14 teams in Qatar underwent a comprehensive strength assessment at the beginning of the 2013/2014 and 2014/2015 seasons...
March 1, 2018: American Journal of Sports Medicine
Nikos C Apostolopoulos, Ian M Lahart, Michael J Plyley, Jack Taunton, Alan M Nevill, Yiannis Koutedakis, Matthew Wyon, George S Metsios
Effects of passive static stretching intensity on recovery from unaccustomed eccentric exercise of right knee extensors was investigated in 30 recreationally active males randomly allocated into three groups: high-intensity (70-80% maximum perceived stretch), low-intensity (30-40% maximum perceived stretch), and control. Both stretching groups performed 3 sets of passive static stretching exercises of 60s each for hamstrings, hip flexors, and quadriceps, over 3 consecutive days, post-unaccustomed eccentric exercise...
March 12, 2018: Applied Physiology, Nutrition, and Metabolism, Physiologie Appliquée, Nutrition et Métabolisme
Mark Roe, Shane Malone, Eamonn Delahunt, Kieran Collins, Conor Gissane, Ulrik McCarthy Persson, John C Murphy, Catherine Blake
OBJECTIVE: Report eccentric knee flexor strength values of elite Gaelic football players from underage to adult level whilst examining the influence of body mass and previous hamstring injury. DESIGN: Cross-sectional study. SETTING: Team's training facility. PARTICIPANTS: Elite Gaelic football players (n = 341) from under 14 years to senior age-grades were recruited from twelve teams. MAIN OUTCOME MEASURES: Absolute (N) and relative (N·kg-1 ) eccentric hamstring strength as well as corresponding between-limb imbalances (%) were calculated for all players...
March 1, 2018: Physical Therapy in Sport
Mark De Ste Croix, Abigail Priestley, Rhodri Lloyd, Jon Oliver
PURPOSE: Fatigue negatively alters dynamic knee control, and the functional hamstring/quadriceps ratio (H/QFUNC ) plays an important role in stabilizing the joint. The aim of this study was to investigate the influence of soccer-specific exercise on H/QFUNC in under (U) 13-, U15-, and U17-year-old female soccer players. METHODS: A total of 36 female players performed concentric and eccentric actions of the hamstrings at 60°, 120°, and 180°/s before and after an age group-specific field-based soccer protocol...
February 27, 2018: Pediatric Exercise Science
Renan F H Nunes, Rodolfo A Dellagrana, Fábio Y Nakamura, Cosme F Buzzachera, Flavia A M Almeida, Lucinar J F Flores, Luiz G A Guglielmo, Sérgio G da Silva
Purpose/Background: Strength asymmetries are related to knee injuries in intermittent sports players. The purpose of this study was to examine whether elite futsal players demonstrate strength asymmetries during knee isokinetic testing applying the Croisier et al.21 criteria. Methods: Forty male elite (27.9 ± 6.5 years) Brazilian futsal players participated in the study. The testing protocol required players to perform concentric contractions of both quadriceps and hamstring muscles at angular velocities of 60 °·s-1 and 240 °·s-1 and eccentric contractions of hamstring at 30 °·s-1 and 120 °·s-1 ...
February 2018: International Journal of Sports Physical Therapy
Gerard Carmona, Jurdan Mendiguchía, Xavier Alomar, Josep M Padullés, David Serrano, Lexa Nescolarde, Gil Rodas, Roser Cussó, Ramón Balius, Joan A Cadefau
Purpose: To investigate the extent and evolution of hamstring muscle damage caused by an intensive bout of eccentric leg curls (ELCs) by (1) assessing the time course and association of different indirect markers of muscle damage such as changes in the force-generating capacity (FGC), functional magnetic resonance (fMRI), and serum muscle enzyme levels and (2) analyzing differences in the degree of hamstring muscle damage between and within subjects (limb-to-limb comparison). Methods: Thirteen male participants performed six sets of 10 repetitions of an ELC with each leg...
2018: Frontiers in Physiology
Giuseppe Coratella, Marco Beato, Chiara Milanese, Stefano Longo, Eloisa Limonta, Susanna Rampichini, Emiliano Cè, Angela Valentina Bisconti, F Schena, F Esposito
The aim of the present study was to compare the effects of weighted jump squat (WJST) vs body mass squat jump training (BMSJT) on quadriceps muscle architecture, lower-limb lean-mass (LM) and muscle strength, performance in change of direction (COD), sprint and jump in recreational soccer-players. Forty-eight healthy soccer-players participated in an off-season randomized controlled-trial. Before and after an eight-week training intervention, vastus lateralis pennation angle, fascicle length, muscle thickness, LM, squat 1-RM, quadriceps and hamstrings isokinetic peak-torque, agility T-test, 10 and 30m sprint and squat-jump (SJ) were measured...
February 6, 2018: Journal of Strength and Conditioning Research
Samantha N Madoni, Pablo B Costa, Jared W Coburn, Andrew J Galpin
PURPOSE: To examine the effects of foam rolling (FR), on range of motion, (ROM), peak torque (PT), hamstrings-to-quadriceps (H:Q) ratios, and muscle activation . METHODS: Twenty-two recreationally active women (mean age ± SD = 21.55 ± 1.82 years, 161.91 ± 6.58 cm, 61.47 ± 10.54 kg) volunteered for this study. Participants performed pre- and post-tests analyzing PT and surface electromyography (EMG) of their dominant limb completing maximal knee extension and flexion at three different velocities...
February 1, 2018: Journal of Strength and Conditioning Research
Clarissa M Brusco, Anthony J Blazevich, Regis Radaelli, Cintia E Botton, Eduardo L Cadore, Bruno M Baroni, Gabriel S Trajano, Ronei S Pinto
Adaptations to 6 weeks of supervised hamstring stretching training and its potential impact on symptoms of eccentric exercise-induced muscle damage (EIMD) were studied in 10 young, untrained men with limited hamstrings flexibility. Participants performed unilateral flexibility training (experimental leg; EL) on an isokinetic dynamometer while the contralateral limb acted as control (CL). Hip range of motion (ROM), passive, isometric and concentric torques, active optimum angle, and biceps femoris and semitendinosus muscle thickness and ultrasound echo intensity were assessed both before and after the training...
February 3, 2018: Scandinavian Journal of Medicine & Science in Sports
Che Hsiu Chen, Ye Xin, Kuang Wu Lee, Ming Ju Lin, Jiu Jenq Lin
The purpose of the study was to examine the acute effects of different dynamic exercise interventions on hamstring muscle performance. Thirty-six young men with poor hamstring flexibility were randomly assigned to three intervention groups: jogging combined with dynamic open kinetic chain stretching (DS), jogging combined with dynamic closed kinetic chain stretching (lunge with eccentric hamstring windmills, LEC), and jogging only (CON) groups. Hamstring flexibility, muscle stiffness (area under the curve, AUC), joint position sense (JPS), maximal eccentric strength (ECC), and angle of peak torque (APT) were recorded before and immediately after the exercise interventions...
2018: PloS One
Alireza Monajati, Eneko Larumbe-Zabala, Mark Goss-Sampson, Fernando Naclerio
The aim of this study was to perform an electromyographic and kinetic comparison of two commonly used hamstring eccentric strengthening exercises: Nordic Curl and Ball Leg Curl. After determining the maximum isometric voluntary contraction of the knee flexors, ten female athletes performed 3 repetitions of both the Nordic Curl and Ball Leg Curl, while knee angular displacement and electromyografic activity of the biceps femoris and semitendinosus were monitored. No significant differences were found between biceps femoris and semitendinosus activation in both the Nordic Curl and Ball Leg Curl...
December 2017: Journal of Human Kinetics
Justin W Y Lee, Ming-Jing Cai, Patrick S H Yung, Kai-Ming Chan
PURPOSE: This study aims to evaluate the test-retest reliability, sensitivity and concurrent validity of a smartphone-based method for assessing eccentric hamstring strength among male professional football players. METHODS: Twenty-five healthy male professional football players have performed CUHK Nordic break-point test, hamstring fatigue protocol and isokinetic hamstring strength test. CUHK Nordic break-point test is based on a Nordic hamstring exercise. The Nordic break-point angle was defined as the maximum point where the participants could no longer support the weight of their body against gravity...
December 28, 2017: International Journal of Sports Physiology and Performance
Justin W Y Lee, Kam-Ming Mok, Hardaway C K Chan, Patrick S H Yung, Kai-Ming Chan
OBJECTIVES: The purpose of this study was to investigate whether preseason isokinetic strength measures were predictive of future HSI among professional football players. DESIGN: Prospective cohort study, Level of evidence 2. METHODS: A total of 169 professional players participated in a preseason isokinetic strength screening, followed by a 10-month competitive season. Testing protocol included the concentric performance of both knee flexion and extension at 60degs-1 and 240degs-1 and the eccentric performance of the knee flexor at 30degs-1...
December 5, 2017: Journal of Science and Medicine in Sport
Mayank Agarwal, Shraddha Singh, Priyanka Sharma, Rahul Saini
BACKGROUND: Muscle-derived interleukin-6 (IL-6) not only enhances glucose and fat metabolism but also has an anti-inflammatory effect that can prevent the development of cardiovascular disease (CVD) and metabolic syndrome. Dynamic resistance exercise comprises a muscle shortening and a lengthening phase known as concentric and eccentric contraction respectively. We compared an acute bout of concentric exercise (CE) with eccentric exercise (EE) for the serum IL-6 concentration, myocardial oxygen consumption (MVO2) and rating of perceived exertion (RPE)...
December 1, 2017: Journal of Sports Medicine and Physical Fitness
Lasse Ishøi, Per Hölmich, Per Aagaard, Kristian Thorborg, Thomas Bandholm, Andreas Serner
This assessor-blinded, randomized controlled superiority trial investigated the efficacy of the 10-week Nordic Hamstring exercise (NHE) protocol on sprint performance in football players. Thirty-five amateur male players (age: 17-26 years) were randomized to a do-as-usual control group (CG; n = 17) or to 10-weeks of supervised strength training using the NHE in-season (IG; n = 18). A repeated-sprint test, consisting of 4 × 6 10 m sprints, with 15 s recovery period between sprints and 180 s between sets, was conducted to evaluate total sprint time as the primary outcome...
December 1, 2017: Journal of Sports Sciences
Brady Green, Matthew N Bourne, Tania Pizzari
OBJECTIVE: To examine the value of isokinetic strength assessment for predicting risk of hamstring strain injury, and to direct future research into hamstring strain injuries. DESIGN: Systematic review. DATA SOURCES: Database searches for Medline, CINAHL, Embase, AMED, AUSPORT, SPORTDiscus, PEDro and Cochrane Library from inception to April 2017. Manual reference checks, ahead-of-press and citation tracking. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Prospective studies evaluating isokinetic hamstrings, quadriceps and hip extensor strength testing as a risk factor for occurrence of hamstring muscle strain...
March 2018: British Journal of Sports Medicine
Matt Greig, James Naylor
Background: Agility is a fundamental performance element in many sports, but poses a high risk of injury. Hierarchical modelling has shown that eccentric hamstring strength is the primary determinant of agility performance. Purpose: The purpose of this study was to investigate the relationship between knee flexor and extensor strength parameters and a battery of agility tests. Study Design: Controlled laboratory study. Methods: Nineteen recreational intermittent games players completed an agility battery and isokinetic testing of the eccentric knee flexors (eccH) and concentric knee extensors (conQ) at 60, 180 and 300°·s-1 ...
October 2017: International Journal of Sports Physical Therapy
András Hegyi, Annamária Péter, Taija Finni, Neil J Cronin
Recent studies suggest region-specific metabolic activity in hamstring muscles during injury prevention exercises, but the neural representation of this phenomenon is unknown. The aim of this study was to examine whether regional differences are evident in the activity of biceps femoris long head (BFlh) and semitendinosus (ST) muscles during two common injury prevention exercises. Twelve male participants without a history of hamstring injury performed the Nordic hamstring exercise (NHE) and stiff-leg deadlift (SDL) while BFlh and ST activity were recorded with high-density electromyography (HD-EMG)...
November 15, 2017: Scandinavian Journal of Medicine & Science in Sports
Anthony J Shield, Matthew N Bourne
Hamstring strain injuries are endemic in running-based sports. Given the economic and performance implications of these injuries, a significant body of research has emerged in recent years in an attempt to identify risk factors and develop or optimise injury prevention strategies. Surveys of injury prevention practices among medical and conditioning staff in elite sport suggest that many sporting clubs invest significant efforts in eccentric hamstring conditioning and lumbo-pelvic or trunk stability programmes...
March 2018: Sports Medicine
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