Muscle Activity of Lower Extremities for Normal Adults According to the Type of Chair and Posture During Sit-to-stand Movement

The purpose of this study is to investigate the effect of sit to stand movement on the muscle activity of lower extremities muscles by the different type of chair and posture. Total 52 healthy adult between 19 and 26 were selected as subject for the study. The muscle activities of vastus lateralis, rectus femoris, vastus medialis, tibialis anterior and gastrocnemius by the different types of chair during sit to stand movement were measured by using surface electromyography WEMG. Sit to stand movement was performed by the different types of chair. For both fixed and wheeled chairs, rectus femoris and vastus lateralis showed a statistically significant difference (p<.05) when standing, while vastus medialis, rectus femoris, and vastus lateralis showed a statistically significant difference when sitting (p<.05). Comparison of standing and sitting positions revealed that all muscle types except gastrocnemius showed a statistically significant difference. This study suggests that it can be useful for providing fundamental data regarding the muscle activation of lower limbs according to chair type.