Woodhull-McNeal A P
Eur J Appl Physiol Occup Physiol. 1986;55(4):419-24. doi: 10.1007/BF00422744.
Electromyographic activity of erector spinae, external oblique, and rectus abdominis muscles was studied during relaxed standing compared to lying down. Activity in the forearm extensors and forearm flexors was also studied. Surface electrodes were used. Each of the torso muscles exhibited 0.2 microV of activity and the forearm muscles 0.1 microV while subjects were relaxed and lying down. During quiet standing the erector spinae, external oblique, and rectus abdominis muscles showed a median activity of 1.0 microV, 2.5 microV, and 0.7 microV respectively (for a minimum of ten 10-sec samples per subject). Examination of the integrated records during standing revealed no periods without increased muscle activity in the torso muscles. By contrast, activity in the forearm muscles did not increase during standing. The major superficial muscles of posture in the torso appear to act as guy wires, being continually active during standing. There is no support for hypotheses of passive support for the torso, nor do torso muscles act in either/or fashion; both anterior and posterior muscles are active at once. There is no sign of generally increased muscle tone in all muscles or in extensors; only the postural muscles are continuously active.
研究了竖脊肌、腹外斜肌和腹直肌在放松站立与躺下时的肌电图活动。同时也研究了前臂伸肌和前臂屈肌的活动。使用了表面电极。受试者放松躺下时，躯干的每块肌肉均表现出0.2微伏的活动，前臂肌肉为0.1微伏。安静站立时，竖脊肌、腹外斜肌和腹直肌的中位活动分别为1.0微伏、2.5微伏和0.7微伏（每位受试者至少采集十个10秒的样本）。对站立期间的整合记录进行检查发现，躯干肌肉没有不增加肌肉活动的时间段。相比之下，站立期间前臂肌肉的活动没有增加。躯干主要的浅层姿势肌似乎起到了拉索的作用，站立时持续活动。没有证据支持躯干被动支撑的假说，躯干肌肉也不是以非此即彼的方式起作用；前后肌肉同时活动。所有肌肉或伸肌均没有普遍肌张力增加的迹象；只有姿势肌持续活动。
