LAUSR

Purpose: Postural instability can increase the risk of a fall in older adults. In this study, the impact of mental fatigue on postural stability among healthy older adults was investigated. Method: Participants were randomly divided into two groups: experimental and control groups. Postural stability of all participants was tested using the Biodex Balance System (BBS) before and immediately after watching a 30-min documentary program (control group) or completing a 30-min Stroop task (experimental group). Subjective ratings of mental fatigue were measured before and after the Stroop task or watching documentary program. Results: The results indicated that experimental group revealed higher stability scores in the posttest compared to pretest (P ≥ 0.001). However, there were no significant differences for BBS scores between pre and posttest in control group (P = .688). In addition, posttest of subjective ratings of mental fatigue was significantly different between experimental and control groups. Finally, there was also evidence of an association between Visual analog scale and BBS scores in the experimental group (rs = 0.712, P = .002). Conclusions: Mental fatigue caused by Stroop task had a negative impact on postural stability in older adults. This may be due to reduction in attentional resources that was caused by mental fatigue. Thus, mental fatigue could be considered as a risk factor for increased risk of falls in older adults.