不同仰臥起坐姿勢之肌電訊號分析

Abstract

目的：探討不同仰臥起坐姿勢對於腹直肌及腹外斜肌之肌電訊號的影響與差異。方法：以八名大專甲組男子體操選手為受試者，實施三種不同仰臥起坐姿勢：1.治療床屈膝仰臥起坐、2.治療床直膝仰臥起坐、3.羅馬椅直膝仰臥起坐等三種動作，以FASTEC IMAGING高速攝影機(125fram/s)及Biopac MP150肌電系統(1250Hz)，擷取三種仰臥起坐動作過程的影片資料及中上腹直肌、下腹直肌及腹外斜肌的肌電訊號參數，所得的結果以無母數檢定（nonparametric tests）之魏克遜符號等級考驗（Wilcoxon檢定）和弗里曼二因子等級變異數分析（Friedman檢定），顯著水準定為α＝ .05。結果：三種仰臥起坐動作的肌電訊號沒有顯著差異，但在直膝仰臥起坐的上腹直肌肌電訊號明顯大於羅馬椅的仰臥起坐。而腹外斜肌的離心收縮肌電訊號，羅馬椅仰臥起坐比直膝仰臥起坐要來得大。肌電訊號顯示，其上、下腹直肌及腹外斜肌在向心收縮的初期0°-60°及離心收縮的末期60°-0°之肌電訊號皆最為明顯；而在向心收縮的末期60°-90°至最高點90°及離心收縮的初期90°-60°之肌電訊號皆較微弱。

The purpose of this study was to evaluate the effects of three specific sit-ups exercises on muscular activity of rectus abdominis and external oblique. Methods : Eight elite college gymnasts were served as the subjects of this study. The upper and the lower part of rectus abdominis and the external oblique muscles were tested in this study when the gymnasts worked in three different sit-up movements, those were the bent knee sit-ups, the straight knee sit-ups and the straight knee sit-ups on Rome bench. The FASTEC IMAGING high-speed camera (125 fram∕s) and the Biopac MP150 (1250Hz) were used to collect the EMG and kinematics data during three specific sit-ups exercises. The Friedman and Wilcoxon Nonparametric statistical test were used to compare all the variables at a .05 significant level. Results: There was no significant difference among three specific sit-ups in EMG signals. The EMG signal of straight knee sit-up was significant greater than the signal of Roman chair sit-up in the upper part rectus abdominis, the Roman chair sit-up eccentric EMG signal was significant greater than the straight knee sit-up in the external oblique muscle. The EMG signals was great on the concentric contraction of 0 degree to 60 degree and the eccentric contraction of 60 degree to 0 degree .