Canu M H, Falempin M
Laboratoire de Plasticité Neuromusculaire, Université des Sciences et Technologies de Lille, Villeneuve d'Ascq, France.
Eur J Appl Physiol Occup Physiol. 1998 Nov;78(6):509-15. doi: 10.1007/s004210050453.
Effects of hindlimb unloading on interlimb coordination were examined in adult rats walking on a treadmill at moderate speed. In the first group of animals, the electromyographic activity (EMG) of soleus muscle of both hindlimbs was recorded after 7 and 14 days of unloading. In the second group, the EMG was recorded daily until the 14th day of unloading. The general organization of locomotion was preserved in the two groups whatever the duration of the unloading. The step cycles of the two hindlimbs were always strictly alternating. However, the locomotor pattern was very irregular. A lateral instability was observed. It was accompanied by an abduction of the hindlimbs, and frequent hyperextensions of the ankle when walking. The EMG analysis showed an increase in step cycle duration and in coactivation duration of the soleus muscles (i.e. in the double stance duration). In the rats recorded daily, mean EMG was dramatically reduced the 1st day of unloading, suggesting a decrease in the neural drive. Taken together, these data indicate that 14 days of hindlimb unloading can alter the neuromuscular pattern during locomotion. It is proposed that these changes are related to changes in the peripheral sensory information.
在成年大鼠以中等速度在跑步机上行走时，研究了后肢卸载对肢体间协调性的影响。在第一组动物中，卸载7天和14天后记录双后肢比目鱼肌的肌电图活动（EMG）。在第二组中，每天记录EMG直至卸载第14天。无论卸载持续时间如何，两组动物的运动总体组织均得以保留。双后肢的步周期始终严格交替。然而，运动模式非常不规则。观察到侧向不稳定。它伴随着后肢外展以及行走时踝关节频繁过度伸展。EMG分析显示步周期持续时间和比目鱼肌的共同激活持续时间增加（即双支撑持续时间增加）。在每天记录的大鼠中，卸载第1天平均EMG显著降低，表明神经驱动减少。综上所述，这些数据表明14天后肢卸载可改变运动过程中的神经肌肉模式。有人提出这些变化与外周感觉信息的变化有关。
