The Laboratory for Motor Control, Department of Medical Informatics, Aalborg University, Aalborg, Denmark.
J Electromyogr Kinesiol. 1991;1(1):1-8. doi: 10.1016/1050-6411(91)90021-V.
We wished to quantify the dynamic muscle fatigue by electromyographic (EMG) and kinematic parameters during uphill walking (5 km/h, 25%). The muscle coordination between biceps femoris, semitendinosus, vastus lateralis, gastrocnemius medialis, soleus, and tibialis anterior was evaluated by measuring (a) the period from onset of the EMG burst to heel contact, and (b) duration of the EMG burst. The muscle activity of the individual bursts was evaluated by the root mean-square (RMS), the mean power frequency (MPF), and the averaged EMG profile during one stride cycle. The most pronounced differences at the start and end of the endurance test were observed in the semitendinosus and the biceps femoris. The gastrocnemius was recruited substantially closer to heel contact, but no changes were noted in the soleus. The RMS and duration of the EMG burst were changed significantly for the vastus lateralis. The overall pattern of the kinematic profiles (position, and velocity) for the upper and lower leg remained constant, although the muscle activity and coordination changed. During dynamic muscle fatigue, a complex interaction between muscle coordination and muscle performance was noted, but how the central nervous system control this interaction is not known.
我们希望通过肌电图（EMG）和运动学参数来量化上坡行走（5km/h，25%坡度）时的动态肌肉疲劳。通过测量（a）从肌电爆发开始到脚跟接触的时间，以及（b）肌电爆发的持续时间，评估股二头肌、半腱肌、股外侧肌、腓肠肌内侧、比目鱼肌和胫骨前肌之间的肌肉协调。通过均方根（RMS）、平均功率频率（MPF）和一个步周期内的平均肌电图图谱评估单个肌电爆发的肌肉活动。在耐力测试的开始和结束时，半腱肌和股二头肌的变化最为明显。腓肠肌在更接近脚跟接触时被大量募集，但比目鱼肌没有变化。股外侧肌的肌电爆发 RMS 和持续时间发生了显著变化。尽管肌肉活动和协调发生了变化，但上下腿的运动学图谱（位置和速度）的整体模式保持不变。在动态肌肉疲劳期间，注意到肌肉协调和肌肉性能之间存在复杂的相互作用，但中枢神经系统如何控制这种相互作用尚不清楚。
