title: Soccer-specific fatigue and eccentric hamstrings muscle strength.
abstract: BACKGROUND
  Epidemiologic findings of higher incidences of hamstrings muscle strains during the latter stages of soccer match play have been attributed to fatigue.
  
  
  OBJECTIVE
  To investigate the influence of soccer-specific fatigue on the peak eccentric torque of the knee flexor muscles.
  
  
  METHODS
  Descriptive laboratory study.
  
  
  METHODS
  Controlled laboratory environment.
  
  
  METHODS
  Ten male professional soccer players (age = 24.7 +/- 4.4 years, mass = 77.1 +/- 8.3 kg, Vo(2max) = 63.0 +/- 4.8 mL x kg(-1) x min(-1)).
  
  
  METHODS
  Participants completed an intermittent treadmill protocol replicating the activity profile of soccer match play, with a passive halftime interval. Before exercise and at 15-minute intervals, each player completed isokinetic dynamometer trials.
  
  
  METHODS
  Peak eccentric knee flexor torque was quantified at isokinetic speeds of 180 degrees x s(-1), 300 degrees x s(-1), and 60 degrees x s(-1), with 5 repetitions at each speed.
  
  
  RESULTS
  Peak eccentric knee flexor torque at the end of the game (T(300eccH105) = 127 +/- 25 Nm) and at the end of the passive halftime interval (T(300eccH60) = 133 +/- 32 Nm) was reduced relative to T(300eccH00) (167 +/- 35 Nm, P < .01) and T(300eccH15) (161 +/- 35 Nm, P = .02).
  
  
  CONCLUSIONS
  Eccentric hamstrings strength decreased as a function of time and after the halftime interval. This finding indicates a greater risk of injuries at these specific times, especially for explosive movements, in accordance with epidemiologic observations. Incorporating eccentric knee flexor exercises into resistance training sessions that follow soccer-specific conditioning is warranted to try to reduce the incidence or recurrence of hamstrings strains.
authors.affiliation: The Football Association, Shropshire, United Kingdom. matt.greig@edgehill.ac.uk
authors.forename: Matt
authors.initials: M
authors.lastname: Greig
authors.forename: Jason C
authors.initials: JC
authors.lastname: Siegler
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001265:Athletic Injuries / Q000209:etiology / Q000517:prevention & control*; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D007719:Knee Joint / Q000503:physiopathology*; D008297:Male; D018763:Muscle Fatigue / Q000502:physiology*; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010807:Physical Endurance; D011336:Probability; D012680:Sensitivity and Specificity; D012916:Soccer / Q000293:injuries / Q000502:physiology*; D013180:Sprains and Strains / Q000209:etiology; D019415:Torque; D055815:Young Adult