Comparison of GPS-derived peak running speed and accelerometer-derived metrics during submaximal running tests for monitoring neuromuscular fatigue in soccer players

This research aims to compare the parameters (Peak running speed and Player Load™ (A.U.)) of a submaximal run test (SRT) and a countermovement jump (CMJ) test used to assess neuromuscular fatigue (NMF) in soccer players. To achieve this, we employed a longitudinal repeated-measures design to assess fatigue-induced changes across multiple time points. Twenty male soccer players volunteered to participate in the study. Participants performed SRT and CMJ tests 24 h pre-game, 24 h post-game, and 48 h post-game. The differences in NMF measurements at these three times were analyzed by repeated measures analysis of variance (ANOVA). The reliability of all NMF measurements was examined based on the coefficient of variation (CV) %, standard error measurement (SEM), and minimum detectable change (MDC ₉₅ ) analysis. There were statistically significant differences between 24 h pre-game, 24 h post-game and 48 h post- game measurements regarding CMJ height (cm); (F = 16.995; p ≤ .001; η2p = 0.472), and SRT parameters; player load 1D up (PL1D _up ) (A.U.) (F = 27.386; p ≤ .001; η2p = 0.590), player load 1D side (PL1D _side ) (A.U.) (F = 21.556; p ≤ .001; η2p = 0.532), player load 1D forward (PL1D _fwd ) (A.U.) (F = 13.590; p ≤ .001; η2p = 0.417), total player load (TPL1D) (A.U.) (F = 21.337; p ≤ .001; η2p = 0.529) and peak speed (m/s) (F = 21.556; p ≤ .001; η2p = 0.532). In conclusion, these findings suggest that peak speed monitoring may serve as a valuable, time-efficient complement to traditional fatigue assessment tools, providing practitioners with a practical, accessible framework for managing player recovery in professional soccer environments.