Investigation of static balance in challenging cognitive task after mental fatigue

The aim of this study was to investigate the effect of mental fatigue on static balance in healthy young adults and the effect of dual-task compared to single-task on static balance in the presence of mental fatigue. For this purpose, assessments were performed in 3 conditions: baseline, mental fatigue condition and dual-task condition. A total of 38 adults, 19 females and 19 males, aged between 18 and 44 years were included in the study. The baseline condition consisted of a 25-minute rest period followed by assessments. Mental fatigue was induced with a 25-minute Stroop test. For the dual task, in addition to the balancing task, they were given the task of subtracting 7 backwards from a number chosen between 300 and 600. Balance assessments in all conditions were performed with a static posturography device. According to the results of the study, it was observed that mental fatigue alone did not affect static balance (p>.05), but the cognitive task added to mental fatigue caused statistically significant high oscillation amounts with medium and large effect sizes (p<.05). The fact that significant increases in oscillations were observed in the static balance assessment in the dual task compared to the single task suggests that mental fatigue may have a significant effect. Keywords: Stroop test, mental fatigue, balance, dual task, postural stability.