Hamstring rate of torque development is more affected than maximal voluntary contraction after a professional soccer match

This is the authors' abstract. We don't add key points for this paper.

Match‐induced fatigue of knee muscle strength and agonist‐antagonist strength‐ratios may affect both performance and risk of injury in soccer players. Once explosive tasks are imperative in soccer as well as hamstring strain injuries occur during high‐velocity moments, rapid force capacity of this muscle group is especially important. This study evaluated the effect of match‐induced fatigue on knee muscle strength and strength‐ratio parameters after a single professional soccer match. Male professional soccer players ( n = 16; 24.2 ± 3.9 years) were tested before and after a soccer match (56.2 ± 22.6 min of playing) for knee flexors (hamstring) and extensors (quadriceps) isometric peak torque (MVC) and rate of torque development (RTD) – as well as the hamstring‐to‐quadriceps ratio (H:Q) – at 30° of knee flexion. Knee injuries often occur at this joint angle, which is common in sprinting, pivoting, sidecutting, and jumping. Match‐induced fatigue caused a left shift in the knee extensors torque‐time curve with no significant change in both early (i.e. 0–50 ms) and late (i.e. 0–200 ms) RTD, and a right shift in the knee flexors torque‐time curve with a decrease in early RTD (∼16%, p = .029) and late RTD (∼11%, p = .011). Knee extensors and knee flexors peak torque remained unchanged ( p > .05). Early RTD H:Q decreased by∼24% ( p = .027), while late RTD H:Q and MVC H:Q remained unchanged ( p > .05). In conclusion, match‐induced fatigue impaired the ability to rapidly produce force at an angle where injuries are most susceptible to occur. Important information is missed if only the traditional H:Q is considered.