Søgaard K
National Institute of Occupational Health, Department of Physiology, Copenhagen, Denmark.
Muscle Nerve. 1995 Mar;18(3):292-300. doi: 10.1002/mus.880180305.
Motor unit (MU) recruitment patterns were studied during dynamic and static contractions at workloads corresponding to 10% of maximal voluntary contraction force. The dynamic contraction consisted of a 20 degrees flexion and extension of the elbow performed with a velocity of 10 degrees/s. Motor unit potential trains were recorded from the brachial biceps muscle of 6 healthy females using a quadripolar needle electrode and a computerized decomposition program. Properties of the identified MUs were derived from concentric needle EMG. A total of 119 MUs were identified during dynamic contractions, 107 MUs during static anisotonic contractions, and 96 MUs during static isotonic contractions. The main result was that MUs recruited during different contractions showed similar properties and may belong to the same part of the motoneuron pool. This indicates that MU recruitment patterns during dynamic contractions may be almost as stereotypical as during static contractions and may even activate the same MUs.
在相当于最大自主收缩力10%的负荷下，研究了动态和静态收缩过程中的运动单位（MU）募集模式。动态收缩包括以10度/秒的速度进行20度的肘关节屈伸。使用四极针电极和计算机化分解程序，从6名健康女性的肱二头肌记录运动单位电位序列。已识别运动单位的特性来自同心针肌电图。在动态收缩过程中总共识别出119个运动单位，在静态非等张收缩过程中识别出107个运动单位，在静态等张收缩过程中识别出96个运动单位。主要结果是，在不同收缩过程中募集的运动单位表现出相似的特性，可能属于运动神经元池的同一部分。这表明动态收缩过程中的运动单位募集模式可能几乎与静态收缩过程一样刻板，甚至可能激活相同的运动单位。
