Effects of Mental Fatigue on Reaction Time in Sportsmen

(Publisert i International  Journal of Environmental Reearch and Public Health, vol 19 nr 21, 2022)

Mental fatigue (MF) has been defined as a psychobiological state commonly caused by prolonged periods of demanding cognitive activity. However, the differences between women and men in their reaction times (RTs) to visual stimuli due to mental fatigue remain largely unknown. We compare the differences in RT and heart rate after an acute intervention of mental fatigue between male and female athletes. For this aim, 64 participants performed a routine of 15 min of the Stroop test (PsyTool), with 600 tasks and five different colors. Their heart rate (HR) was registered before, during, and one, three, and five minutes after the Stroop test. Meanwhile, the RT was evaluated before and after the Stroop test. A general linear mixed model (GLMM) and a Bonferroni post-hoc test were used to compare the HR between the conditions and an ANOVA two-way analysis was used to compare the values pre-/post-Stroop test. The GLMM for HR showed an effect on the time and the time × group interaction. The RT was significantly increased pre- to post-Stroop test; however, there was no difference between the pre- and post-HR measurements and the measurements one, three and five min after the Stroop test. The present findings suggest that the parasympathetic branch of the autonomous nervous system which functions as a relaxation system tends to be activated under increasing mental fatigue, with a decreased performance (RT) similarly in men and women. Therefore, athletes could exploit MF induced during training to improve the time delay related to specific motor tasks.