The Effect of Mental Fatigue on Upper Extremity Functional Performance

Mental fatigue (MF) is known to impair cognitive performance and may negatively affect physical performance. While its effects on lower-extremity functional performance have been investigated, little is known about the influence of MF on upper-extremity physical performance tests commonly used in sports and rehabilitation settings. This randomized crossover study will investigate the effects of experimentally induced mental fatigue on upper-extremity physical performance in 16 healthy physically active adults. Participants will complete both a mental fatigue condition, involving a prolonged Stroop task, and a control condition consisting of watching an emotionally neutral documentary. Before and after each condition, participants will perform the Upper Quarter Y Balance Test, Reactive Upper Quarter Y Balance Test, Closed Kinetic Chain Upper Extremity Stability Test, and Seated Single-Arm Shot Put Test. Subjective mental fatigue, cognitive performance, motivation, and perceived exertion will also be assessed. The findings will improve understanding of whether mental fatigue influences upper-extremity physical performance test outcomes and may assist clinicians and researchers in interpreting these assessments in sports medicine and rehabilitation contexts.

Inclusion Criteria: * Age between 18 and 35 years * Healthy (no neurological, cardiovascular or musculoskeletal disorders of any kind) * Male or female * No prior knowledge of the concept of mental fatigue * Not currently taking medications that affect cognition or neuromuscular performance * According to the International Physical Activity Questionnaire, being physically active at a minimum level of 1500 MET-min/week Exclusion Criteria: * Previous major upper limb injury (last 6 months) * Involvement in another concurrent physical or cognitive intervention study * Use of caffeine and heavy efforts 24 hours prior each trial * Suffering from colour vision deficiencies * Not eating a standardized meal, the morning of each trial and the evening before each trial