Accessory muscle activity contributes to the variation in time to task failure for different arm postures and loads.
Accessory muscle activity contributes to the variation in time to task failure for different arm postures and loads.
复制标题
对于不同的手臂姿势和负荷，辅助肌肉活动会导致任务失败的时间变化。
DOI：
10.1152/japplphysiol.00564.2006
复制
发表时间：
2007
影响因子：
3.3
通讯作者：
R. Enoka
中科院分区：
文献类型：
--
作者：
T. Rudroff;B. Barry;Amy L. Stone;C. J. Barry;R. Enoka
在两种类型的肘关节屈肌持续次极大收缩期间，测量了失效时间和肌电图活动，这两种类型的持续次极大收缩要求每个受试者在两种不同的姿势下用前臂施加相同的净肌肉扭矩。20名男性执行任务，要么在推力传感器时保持恒定的力（力任务），要么在保持恒定的肘部角度时支撑等效负载（位置任务）。肘关节屈曲为1.57 rad，前臂水平时，体位任务的失败时间少于力任务（5.2 +/- 2.6和8.8 +/- 3.6 min, P = 0.003），而前臂垂直时，失败时间相似（7.9 +/- 4.1和7.8 +/- 4.5 min, P = 0.995）。在两种前臂姿势中，体位任务（25.1 +/- 10.1%最大自主收缩）时肩袖肌肉的活动度大于力任务（15.2 +/- 5.4%最大自主收缩，P < 0.001）。然而，只有当前臂水平时，副肌肌电图和平均动脉压的增加率才会在位置任务中增加（P < 0.05），而肘关节屈肌的增加率相似。这些发现表明，前臂姿势影响两种疲劳收缩的失败时间差异。当两项任务之间存在差异时，距离失败时间较短的任务涉及到副肌活动和平均动脉压的更高增长率。
Time to failure and electromyogram activity were measured during two types of sustained submaximal contractions with the elbow flexors that required each subject to exert the same net muscle torque with the forearm in two different postures. Twenty men performed the tasks, either by maintaining a constant force while pushing against a force transducer (force task), or by supporting an equivalent load while maintaining a constant elbow angle (position task). The time to failure for the position task with the elbow flexed at 1.57 rad and the forearm horizontal was less than that for the force task (5.2 +/- 2.6 and 8.8 +/- 3.6 min, P = 0.003), whereas it was similar when the forearm was vertical (7.9 +/- 4.1 and 7.8 +/- 4.5 min, P = 0.995). The activity of the rotator cuff muscles was greater during the position tasks (25.1 +/- 10.1% maximal voluntary contraction) compared with the force tasks (15.2 +/- 5.4% maximal voluntary contraction, P < 0.001) in both forearm postures. However, the rates of increase in electromyogram of the accessory muscles and mean arterial pressure were greater for the position task only when the forearm was horizontal (P < 0.05), whereas it was similar for the elbow flexors. These findings indicate that forearm posture influences the difference in the time to failure for the two fatiguing contractions. When there was a difference between the two tasks, the task with the briefer time to failure involved greater rates of increase in accessory muscle activity and mean arterial pressure.
影响因子：
3.3
作者：
K. Maluf;R. Enoka
通讯作者：
K. Maluf;R. Enoka
对静态肌肉收缩的升压反射反应：其传入臂和可能的神经递质。
DOI：
10.1016/s0002-9149(88)80013-4
发表时间：
1988
期刊：
The American journal of cardiology
影响因子：
--
作者：
Kaufman,MP;Rotto,DM;Rybicki,KJ
通讯作者：
Rybicki,KJ
肌肉传入在疲劳期间抑制运动神经元中的作用。
影响因子：
--
作者：
Garland,SJ;Kaufman,MP
通讯作者：
Kaufman,MP