The purpose of this study was to compare the change in electromyography (EMG) activity in the gluteus maximus (G-max) and the gluteus medius (G-med) in subjects with and without chronic ankle instability (CAI) during three functional postures. Twenty four females were recruited for this study. Subjects were assigned into two groups: with CAI (n1=12) and without CAI (n2=12). The assessment postures were rotational squat, one leg stand above a gradient and crossed leg-sway. Electromyographic activities of the G-max and the G-med were recorded using surface EMG and was normalized using the maximal voluntary isometric contraction elicited using a manual muscle testing. Independent t-test was used to determine the statistical differences between two groups during the three functional postures. The comparisons of the three posture between two groups were performed using a one-way repeated analysis of variance. A Bonferroni adjustment used for post hoc analysis. The activation of EMG on G-max performing the one leg stand above a gradient and crossed leg-sway in subjects with CAI is significantly higher than normal group (p<.05). The activation of EMG on the G-max during the rotational squat was significantly increased, compared to those of the one leg stand above a gradient and crossed leg-sway (p<.05). The activation of EMG on G-med performing three exercise at CAI is significantly higher than normal group (p<.05). The activation of EMG on the G-med during the crossed leg-sway was significantly increased, compared to the rotational squat (p<.05). This study provides valuable information for clinician who research CAI.

The purpose of this study was to examine the effect of three cognitive tasks on gait at a preferred walking speed, and at a fast speed, using dual-task methodology. A total of 29 stroke patients participated in the study. All 29 subjects performed 2 motor tasks (10-meter walk task and timed up and go task each at a preferred and a fast speed) and three cognitive tasks [Stroop, word list generation (WLG), serial subtraction (SS)] under dual-task conditions [cognitive-motor interference (CMI)] in a randomized order. Gait speeds were measured in six different conditions. A repeated-measure analysis of variance was employed to compare the results of the Stroop training, WLG, and SS tasks during preferred and fast walking. A Bonferroni adjustment use for post hoc analysis. The level of statistical significance was set at α=.05. A CMI effect occurred for performance of a 10-meter walking task at two different speed and a cognitive task (p＜.05). Stroop had a significantly greater effect than SS and WLG (p＜.05). The timed up and go task was affected when performed with fast walking speed during Stroop cognitive task (p＜.05), but was not affected if performed with preferred walking speed during a cognitive task (p＞;.05). This study showed that CMI of Stroop can be used as a rehabilitation program for stroke patients.