The Effect of Mental Fatigue on Performance in Endurance Tasks: A Systematic Review

Abstract

Mental fatigue affects not only cognitive performance, but also physical performance. The main objective of this study was to review the existing literature on the influence of mental fatigue on the ability to withstand sustained physical efforts (endurance tasks). For this purpose, we performed a systematic literature review in the online databases Web Of Science, PubMed and Scopus with the following search terms and Boolean conjunctions: mental fatigue or cognitive fatigue and exercise or endurance and time to exhaustion or time trial or running or cycling. A total of 28 articles, comprising 29 interventions, were included with a high methodological quality (range: 6-8 points out of 10 possible) measured using the PEDro scale. A total of 86% of the included interventions show that mental fatigue reduces performance in the endurance tests compared to a control condition without mental fatigue. In addition, mental fatigue increases the subjective perception of effort, without altering heart rate or blood lactate concentration. Therefore, the results show the importance of avoiding any activity that involves high cognitive demands prior to training or competition events, due to the detrimental effects on endurance capacity.