Voluntary control of forward leaning posture relates to low-frequency neural inputs to the medial gastrocnemius muscle
Voluntary control of forward leaning posture relates to low-frequency neural inputs to the medial gastrocnemius muscle
复制标题
前倾姿势的自主控制与腓肠肌内侧肌的低频神经输入有关
DOI：
10.1016/j.gaitpost.2018.11.026
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发表时间：
2018
期刊：
影响因子：
2.4
通讯作者：
Christou EA
中科院分区：
文献类型：
--
作者：
Watanabe T;Nojima I;Sugiura H;Yacoubi B;Christou EA
背景可变性是运动输出的固有特征。虽然低频振荡（<0.5 Hz）是在单关节孤立力任务期间力的可变性的最重要贡献者，目前尚不清楚它们是否有助于更复杂任务的可变性，例如自愿姿势任务。研究问题低频振荡是否有助于姿势摇摆（压力中心（COP）的变化），当参与者试图自愿保持姿势前倾的位置？方法14名健康青年人完成两项任务：1）安静站立（对照组）; 2）通过背伸踝关节使身体前倾至最大倾斜距离的60%。我们记录了COP和肌电图（EMG）活动从内侧腓肠肌（MG）和比目鱼肌（SL）。我们量化了以下内容：1）作为前后COP位移的标准偏差（SD）的COP变异性; 2）作为从0到2 Hz的COP位移中的功率的COP的调制; 3）作为从0到2 Hz的整流和平滑的EMG中的功率的EMG爆发的调制; 4）将干扰肌电调制为10 ~ 35和35-60 Hz的肌电功率。安静站立和倾斜任务中均为0.5 Hz。然而，只有在倾斜任务中，<0.5Hz的COP振荡与MG肌肉<0.5Hz的EMG爆发振荡相关。MG肌肉的<0.5Hz的EMG爆发振荡进一步与从35到60 Hz的干扰EMG振荡相关，用于leantask.SignificanceVoluntary控制前倾姿势与MG肌肉的低频神经输入有关。
BackgroundVariability is an inherent feature of the motor output. Although low-frequency oscillations (<0.5 Hz) are the most important contributor to the variability of force during single-joint isolated force tasks, it remains unclear whether they contribute to the variability of a more complex task, such as a voluntary postural task.Research questionDo low-frequency oscillations contribute to postural sway (center of pressure (COP) variability) when participants attempt to voluntarily maintain posture in a forward leaning position?MethodsFourteen healthy young adults performed two tasks: 1) stand quietly (control condition); 2) leaned their body forward to 60% of their maximum lean distance by dorsiflexing the ankle joint. We recorded the COP and electromyographic (EMG) activity from the medial gastrocnemius (MG) and soleus (SL) muscles. We quantified the following: 1) COP variability as the standard deviation (SD) of anteroposterior COP displacements; 2) modulation of COP as the power in COP displacements from 0 to 2 Hz; 3) modulation of EMG bursting as the power in the rectified and smoothed EMG from 0 to 2 Hz; 4) modulation of the interference EMG as the power in the EMG from 10 to 35 and 35–60 Hz.ResultsThe SD of COP displacements related to the COP oscillations <0.5 Hz in both quiet standing and lean tasks. However, only for the lean task, the <0.5 Hz COP oscillations related to the EMG burst oscillations <0.5 Hz of the MG muscle. The EMG burst oscillations <0.5 Hz of the MG muscle further related to the interference EMG oscillations from 35 to 60 Hz for the lean task.SignificanceVoluntary control of forward leaning posture relates to low-frequency neural inputs to the MG muscle.