Purpose: To determine the recovery kinetics of performance, muscle damage, and neuromuscular fatigue following 2 speed-endurance maintenance training (SEMT) protocols in soccer.
Methods: Ten well-trained male soccer athletes randomly completed 3 trials: work-to-rest ratio SEMT/1:3, SEMT/1:1, and a control trial. Training load during SEMT was monitored using a global positioning system and heart-rate monitors. Isokinetic strength of knee extensors and flexors; repeated-sprint ability (RSA); speed 10-, 30-m, countermovement jump (CMJ); and muscle damage (delayed-onset muscle soreness [DOMS] and creatine kinase) markers were evaluated at baseline and at 0, 24, 48, and 72 hours posttraining. Maximal voluntary contraction of knee extensors and flexors was additionally assessed at 1, 2, and 3 hours posttraining.
Results: Strength (eccentric torque) and speed performance (RSA, 10-m and 30-m sprint times) were reduced (P < .05) following the SEMT/1:3 for up to 72 and 48 hours, respectively, and following SEMT/1:1 for up to 48 and ≤24 hours, respectively. Eccentric torque and RSA deterioration was greater in SEMT/1:3 compared to SEMT/1:1 at 72 hours and immediately postexercise, respectively (P < .05). Indicators of neuromuscular fatigue (CMJ and maximal voluntary contraction) declined in SEMT/1:3 at 24 and 2 hours postexercise (P < .05) and in SEMT/1:1 immediately and at 2 hours postexercise (P < .05). Muscle damage (DOMS) in the knee flexors was elevated in both SEMT protocols for up to 48 hours (P < .05).
Conclusions: SEMT/1:3 induces short-term neuromuscular fatigue; provokes a decrease of strength (48-72 h), speed and RSA (48 h), and jump height (24 h); and is related with an elevation of knee flexors' DOMS (48 h). Increased work-to-rest ratio causes higher levels of exercise-induced muscle damage.
Keywords: association football; muscle damage; neuromuscular fatigue.