Mental Fatigue Impairs Temporal Perceptual Prediction: A Study on Boxing Performance Across Skill Levels.

Objective: This study investigated the impact of mental fatigue on the temporal perceptual prediction of action recognition among boxers of different skill levels.

Methods: A mixed experimental design of two (groups: Mental Fatigue Expert Group and Mental Fatigue Novice Group) × two (technique types: attack and defense) × three (time shields: -80 ms, -40 ms, and action start) was implemented. Twenty expert and novice boxers participated in this study. Mental fatigue was induced using a 45-min Stroop paradigm, and the effects were assessed using the VAS, Brog-20, BRUMS-F, and BRUMS-V. The experimental procedure for time perception was developed using E-prime 3.0, incorporating 36 videos depicting various attack and defense techniques, and reaction time and accuracy were recorded.

Results: (1) A significant main effect on reaction time (RT) was observed (F (1,38) = 5.97, p < 0.05, η² = 0.14) but not on accuracy (ACC), suggesting a pronounced influence of mental fatigue on novice boxers' temporal perceptual prediction in action recognition; (2) significant main effects of skill types were noted in both RT (F (1,38) = 9.03, p < 0.05, η² = 0.19) and ACC (F (1,38) = 18.496, p < 0.05, η² = 0.327), indicating disparities in the recognition of offensive and defensive skills under mental fatigue; (3) temporal shielding significantly influenced both RT (F (2,76) = 31.42, p < 0.05, η² = 0.45) and ACC (F (2,76) = 125.727, p < 0.05, η² = 0.768), with -80 ms showing a lower RT and ACC compared to -40 ms and action initiation; (4) second-order interaction effects were present in both RT (F (2,76) = 9.85, p < 0.05, η² = 0.21) and ACC (F (2,76) = 8.773, p < 0.05, η² = 0.188), with the RT interaction suggesting a negative impact on perceptual prediction at -80 ms and a faster offensive RT than defensive RT. The ACC interaction indicated that under mental fatigue, -40 ms approached and exceeded -80 ms in both offensive and defensive actions, with higher ACC in offense than defense; and (5) a third-order interaction effect among group, technique type, and time shielding on RT (F (2,76) = 3.92, p < 0.05, η² = 0.09) suggests that mental fatigue more significantly affects novice defensive technique RT than offensive technique.

Conclusions: (1) The 45-min Stroop task effectively induced mental fatigue. (2) Mental fatigue negatively impacts both expert and novice boxers, with a more pronounced effect on experts' defensive skills. (3) The -40 ms time perception is crucial for predicting action recognition as it approaches action initiation.