Mental fatigue in football: methodology and experimental protocol

Mental fatigue, induced by prolonged cognitive demands, impairs attention, decision-making, and motor coordination, potentially compromising performance in cognitively demanding sports such as football. This study presents a randomised controlled experimental design pre-test/post-test protocol designed to investigate the effects of mental fatigue on neurophysiological, visual, technical, and motor performance in football players. Thirty-four athletes (17 men, 17 women; aged ≥18 years; ≥1-year competitive experience) will be randomly assigned to either a cognitive fatigue induction group (30 min Stroop Task) or a low cognitive load control group. Data collection will include EEG (theta and alpha bands), eye tracking (fixation, saccades, pupil dynamics), sport-specific tasks (Loughborough Soccer Passing Test, Y-Shaped Agility Reaction Test), and subjective fatigue ratings (Fatigue Assessment Scale; Visual Analogue Scale). Statistical analyses will encompass intra- and inter-group comparisons, correlation and regression models. By integrating subjective, physiological, and performance indicators in a sport-specific, ecologically valid design, this protocol aims to deepen understanding of how mental fatigue affects performance and to inform individualized monitoring and intervention strategies in high-performance contexts. As a protocol paper, no data are yet available. However, based on previous literature, mental fatigue is expected to be associated with changes in EEG oscillatory activity, less efficient gaze behaviour, and impaired football-specific performance compared to the control condition.