Ochia Ruth S, Cavanagh Peter R
Department of Orthopedic Surgery, Rush University Medical Center, 600 S. Paulina St., 761A Armour Academic Center, Chicago, IL 60612, USA.
J Electromyogr Kinesiol. 2007 Jun;17(3):365-71. doi: 10.1016/j.jelekin.2006.01.003. Epub 2006 May 24.
Bone and muscle are both compromised during long-term space flight. Experiments are, therefore, in progress using surface electromyography (EMG) and joint angle measurements to compare muscle action on earth and in space over complete working days. To date, there is little information on the reliability of such long-term EMG measurements available in the literature. Therefore, the current study determined the reliability and feasibility of using surface EMG over a 12-h interval. Ten young subjects performed standardized isometric exercises at 30% of maximum voluntary effort every 2h throughout a normal working day, which included a period of self-chosen exercise. Surface electrodes remained in place over the biceps brachii (BB), vastus medialis (VM), and gastrocnemius (GN) throughout the day. The normalized integrated EMG for two of the three muscles showed no significant changes during the 12-h period, and only the first observation for VM showed a trend (p<0.1) of differences with three of the other measurement periods. The stability of surface EMG measurements over the 12-h period suggests that this methodology is feasible for use in future long-term EMG studies.
在长期太空飞行期间，骨骼和肌肉都会受到影响。因此，目前正在进行实验，利用表面肌电图（EMG）和关节角度测量来比较在地球上和太空中完整工作日期间的肌肉活动情况。迄今为止，文献中关于这种长期肌电图测量可靠性的信息很少。因此，本研究确定了在12小时时间段内使用表面肌电图的可靠性和可行性。10名年轻受试者在正常工作日期间，每隔2小时以最大自主用力的30%进行标准化等长运动，其中包括一段自主选择的运动时间。一整天中，表面电极一直置于肱二头肌（BB）、股内侧肌（VM）和腓肠肌（GN）上。三块肌肉中的两块肌肉的标准化积分肌电图在12小时期间没有显著变化，只有股内侧肌的第一次观察结果显示与其他三个测量时间段存在差异趋势（p<0.1）。表面肌电图测量在12小时期间的稳定性表明，这种方法在未来的长期肌电图研究中是可行的。
