Practice Under Physical Fatigue: Motor Learning, Fatigue Resilience, and Individual Differences in Healthy Young...

We investigated whether practicing under physical fatigue induced by cardiovascular exercise influences motor performance and learning in a non-fatigued limb, and whether demographic and physiological factors relate to variability in these effects. Sixty participants were randomly assigned to a Fatigue group (FATIGUE), who performed the 20-m multistage shuttle run test to exhaustion before practice, or a Control group (CONTROL), who performed stretching exercises. Both groups practiced a visuomotor tracking task (VTT) and completed rested and fatigued retention tests. Group-level effects were evaluated with repeated-measures ANOVAs. To examine individual-difference patterns, we conducted exploratory network analyses including sex, body mass index (BMI), maximal oxygen consumption (VO₂max), and perceived exertion (BORG), followed by confirmatory models testing state-dependent retention and moderation. Both groups improved from pre- to post-test and maintained gains at rested and fatigued retention, with no reliable between-group differences, indicating that practicing under physical fatigue did not impair motor learning or enhance fatigue "resilience" at the group level. The fatigue protocol increased exertion and heart-rate responses in FATIGUE during acquisition, whereas both groups showed substantial and comparable fatigue responses during the fatigued-retention. Exploratory networks suggested group-specific association patterns, but confirmatory models provided limited evidence for systematic moderation.