The Effects of Lower Limb and Trunk Muscle Activation on Seat Angle and Height during Sit to Stand and Stand to Sit

Abstract

PURPOSE: This study investigated the effects of lower limb and trunk muscles activation on seat angle and height during sit to stand and stand to sit. METHODS: Subjects were instructed to sit and stand on different angles and heights; (43cm), (48cm), (51cm) and (58cm). Measurements were conducted from sit to stand and stand to sit for external oblique, transversus abdominis, rectus femoris, vastus medialis, vastus lateralis, tibialis anterior and gastrocnemius muscle activation by surface EMG. The muscle activation was measured three times for five seconds in each posture, and the %RVC value was calculated after the exclusion of one second before and after this measurement. This calculation standardized the data from each participant so it could be comparatively analyzed. RESULTS: The external oblique, tibialis anterior, and erector spinae muscles showed significant difference in (51cm), (58cm) and (43cm), rectus femoris, in (58cm) and (43cm)(p(43cm) and (58cm), erector spinae and vastus medialis muscles showed significant difference in (51cm), (58cm) and (43cm)(P