Etiology and recovery of knee extensor muscle fatigue following simulated basketball match-play

This study investigated the etiology and recovery of knee extensor muscle fatigue following simulated basketball match-play. Thirteen adult male competitive basketball players (age: 25±4 years, stature: 185±9 cm, body mass: 86±14 kg, body fat: 13±4%) completed a simulated match-play (i.e., the Basketball Activity Simulation Protocol) consisting of standardized specific match-based basketball activities. Before (PRE) and immediately after (POST) the match-play, the neuromuscular function of the knee extensors was evaluated to determine the amount of muscle fatigue and its origin. Assessments were also repeated 24 h (POST24) and 48 h (POST48) after the match-play to evaluate muscle fatigue recovery. The main outcomes were maximal voluntary contraction (MVC) torque, voluntary activation estimated through superimposed stimuli, electrically evoked twitch and doublet peak torque (PT), and the 10:100 Hz doublet ratio. The Total Quality Recovery (TQR) scale was used to assess the perceived recovery status at PRE, POST24 and POST48. Time-related changes (one way repeated measures ANOVA) were observed for MVC torque (main effect: P = 0.002, moderate; post hoc: POST < PRE, small), twitch and doublet PT (P < 0.001, strong; POST < PRE, POST24 and POST48, moderate -to-large) and 10:100 Hz doublet ratio (P < 0.001, strong; POST < PRE, POST24 and POST48, large; POST48 > PRE, moderate). Voluntary activation and TQR were not affected at the different time-points (P = 0.060 and P = 0.455, minimum, respectively). In conclusion, basketball match-play significantly reduced knee extensor MVC strength, with baseline levels being restored within 24 h. Muscle fatigue was accompanied by a significant pre-to-post match reduction of electrically-evoked torque responses, indicative of peripheral fatigue (and evidence of low frequency fatigue), while no signs of central fatigue were noted.