The Effects of Acute Aerobic Exercise and Caffeine Ingestion prior to a Mentally-fatiguing Task
Abstract
Mental fatigue negatively affects the productivity and health of the general population. Mental fatigue manifests following sustained mental activity and is defined by subjective feelings of inhibition and objective decrements in mental performance. Caffeine is one of the most common stimulants used to mitigate mental fatigue. However, regular caffeine consumption is associated with several side effects. The efficacy of acute aerobic exercise as an alternative mental fatigue intervention remains ambiguous. Thus, the present study compared 1) 20 minutes of moderate-intensity cycling, 2) consumption of 2.5 mg/kg of caffeine, and 3) placebo on objective (Psychomotor Vigilance Task) and subjective (visual analog scales) mental fatigue measures, following a 30-minute fatigue-induction task (Stroop task). Twenty-one caffeine consumers completed each aforementioned treatment. The accrual of mental fatigue was mitigated after caffeine consumption, but not acute exercise. Further investigations are warranted to determine the optimal dose of acute exercise for mitigating mental fatigue.