Journal of Athletic Training 2009;44(2):180–184 g by the National Athletic Trainers’ Association, Inc www.nata.org/jat
original research
Soccer-Specific Fatigue and Eccentric Hamstrings Muscle Strength
Matt Greig, PhD*; Jason C. Siegler, PhD, ATCÀ
*The Football Association, Shropshire, United Kingdom; 3University of Hull, Hull, United Kingdom. Dr Greig is now at Edge Hill University, Lancashire, United Kingdom.
Context: 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. Design: Descriptive laboratory study. Setting: Controlled laboratory environment. Patients or Other Participants: Ten male professional soccer players (age 5 24.7 6 4.4 years, mass 5 77.1 6 8.3 kg, ˙ VO2max 5 63.0 6 4.8 mL?kg21?min21). Intervention(s): 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. Main Outcome Measure(s): Peak eccentric knee flexor torque was quantified at isokinetic speeds of 1806 ? s21, 3006 ? s21, and 606 ? s21, with 5 repetitions at each speed. Results: Peak eccentric knee flexor torque at the end of the game (T300eccH105 5 127 6 25 Nm) and at the end of the passive halftime interval (T300eccH60 5 133 6 32 Nm) was reduced relative to T300eccH00 (167 6 35 Nm, P , .01) and T300eccH15 (161 6 35 Nm, P 5 .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...