Friedli W G, Hallett M, Simon S R
J Neurol Neurosurg Psychiatry. 1984 Jun;47(6):611-22. doi: 10.1136/jnnp.47.6.611.
Normal subjects made bilaterally symmetric rapid elbow flexions or extensions ("focal movement") while free standing or when supported by being strapped to a firm wall behind them (different "postural set"). In some trials a load opposed the movement two thirds of the way into its course. Electromyographic activity in leg and trunk muscles ("associated postural adjustments") demonstrated specific patterns for each type of movement. Activity in these muscles began prior to activity in the arm muscles and demonstrated a distal-to-proximal order of activation. The EMG patterns were characterised by alternating activity in the antagonist pairs similar to the triphasic pattern seen in the arm muscles. When the movement type was changed change of the pattern of the postural muscles occurred over several trials. It is concluded that the associated postural adjustments are pre-programmed motor activity linked to the focal movement, specific for the focal movement including anticipated events and the postural set.
正常受试者在自由站立时或被绑在身后的坚固墙壁上获得支撑时（不同的“姿势设定”），进行双侧对称的快速肘部屈伸（“局部运动”）。在一些试验中，在运动进行到三分之二的路程时，有一个负荷对抗运动。腿部和躯干肌肉的肌电图活动（“相关姿势调整”）显示出每种运动类型的特定模式。这些肌肉的活动在手臂肌肉活动之前开始，并显示出从远端到近端的激活顺序。肌电图模式的特征是拮抗肌对中的交替活动，类似于在手臂肌肉中看到的三相模式。当运动类型改变时姿势肌肉模式的改变会在几次试验中发生。得出的结论是，相关的姿势调整是与局部运动相关的预先编程的运动活动，特定于包括预期事件和姿势设定在内的局部运动。
