Motor unit activation patterns during the alternate activity in the synergistic muscles

协同肌交替活动期间运动单位的激活模式

基本信息

批准号：
10680043
负责人：
KURATA Hiroshi
金额：
$ 2.18万
依托单位：
National Institute of Fitness and Sports in Kanoya
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10680043/
关键词：
rotational activity motor unit triceps surae muscle

项目摘要

This study has focused on five points to investigate the alternate activity in the triceps surae muscles ;(1) controlling the emergence of alternate muscular activity, (2) functional interrelationships between joint angle, force output and electromyographic (EMG) activity, (3) characteristics of EMG patterns during alternate muscular activity, (4) single motor unit activity during alternate activity in the synergistic muscles and (5) significance of alternate activity in the static muscle work.EMG-angle relationships showed direct and inverse proportion in gastrocnemius (MG, LG) and soleus (SOL) muscle respectively. There was a quasi-linear relationship between force and EMG in SOL, but MG and LG took on a curvilinear relationship. It was found that prolonged isometric contractions at 110 degrees of ankle joint angle under relatively low level workload (10% maximal voluntary contraction) resulted in the frequent occurrence of alternate muscular activity. Moreover, quantitative analysis revealed the existence of the EMG overlap not only in time but also in magnitude during the alternate activity among synergistic three muscles. In the overlap periods, on the other hands, there is no hysteresis in activation patterns of single motor units during recruitment and derecruitment. Therefore, the reverse pattern of synaptic input to a-motoneurons during recruitment would not be applied to that during derecruitment. Finally, it is suggested that the type of alternate activity in the synergistic muscles reduce the development of muscle fatigue and keep the functional ability for muscle endurance and maximal force output on the next day.

This study has focused on five points to investigate the alternate activity in the triceps surae muscles ;(1) controlling the emergence of alternate muscular activity, (2) functional interrelationships between joint angle, force output and electromyographic (EMG) activity, (3) characteristics of EMG patterns during alternate muscular activity, (4) single motor unit activity during alternate activity in the synergistic muscles and (5) significance of alternate activity in the静态肌肉工作。emg-andle关系分别显示甲状腺素（MG，LG）和比目鱼（Sol）肌肉的直接和反比比例。 SOL中的力与EMG之间存在准线性关系，但是MG和LG呈曲线关系。发现在相对较低的工作量下（10％最大自愿收缩）在110度的踝关节角度上长时间的等距收缩导致频繁出现交替的肌肉活性。此外，定量分析揭示了EMG的存在不仅在及时，而且在协同三个肌肉之间的替代活性期间的大小上存在重叠。在重叠时期，另一方面，在募集和剥落过程中，单电动机单位的激活模式没有滞后。因此，在募集过程中，突触输入对A-----------在剥落过程中不会应用。最后，建议在协同肌肉中的替代活动类型减少了肌肉疲劳的发展，并在第二天保持肌肉耐力和最大力量的功能能力。