[Purpose] The aim of this study was to use surface electromyography (EMG) to investigate
the effects of different foot positioning on bilateral erector spinae (ES) and gluteus
maximus (GM) activation during sit-to-stand performed by individuals with stroke.
[Subjects] Fifteen randomly selected participants with stroke were enrolled in this study.
[Methods] All the participants were asked to perform sit-to-stand (STS) using three
different strategies: (1) symmetric foot position, (2) unaffected foot placed behind the
affected foot position (asymmetric-1), (3) affected foot placed behind the unaffected foot
position (asymmetric-2). An EMG system was used to measure ES and GM muscle activities.
The strategies were performed in a random order, and the mean values of five measurements
were used in the analysis. One-way repeated measure ANOVA was used to determine the
statistical significance of differences between the conditions. [Results] The affected ES
muscle activity was significantly greater in asymmetric-2 (180.7±73.4) than in symmetrical
foot placement (149.8±54.2). In addition, the affected ES, unaffected ES, and affected GM
muscle activity were significantly greater in asymmetric-2 (180.7±73.4, 173.5±83.1,
98.3±90.3 respectively) than in asymmetric-1 foot placement (147.3±53.8, 151.2±76.5,
84.9±73.8 respectively). [Conclusion] Our results suggest that it may be more desirable
for persons with stroke to place the affected foot behind the unaffected foot when
performing STS to increase affected ES and GM muscle activation.