Hayes K C
Eur J Appl Physiol Occup Physiol. 1975 Apr 4;34(2):69-79. doi: 10.1007/BF00999918.
Effects of three different fatiguing local muscular exercises upon plantar flexion reaction time and achilles tendon reflex time have been studied in 24 normal males. The Exercise Conditions, each involving a series of 30 maximal voluntary isometric contractions (MVC) of the plantar flexors, differed by allowing either 5, 10 or 20 sec rest interval between each MVC. Decrements in strength ranged from 15% to 34% MVC. Trend analysis of the fatigue patterns revealed that a cubic orthogonal polynomial equation was sufficient to describe the profile of MVC decrement for all conditions. Following the fatiguing exercise, simple visual reaction time (plantar flexion), and its two components, premotor and motor time, failed to demonstrate any change from Pre Exercise Conditions. Achilles Tendon Reflex Times, however, demonstrated a marked augmentation, as manifest in reduced total reflex times, contraction times and half relaxation times. These results may suggest the differential fatigue of motor units employed in the three motor tasks, viz. MVC, voluntary reaction and achilles tendon reflex. A plausible explanation for the augmentation of the reflex contraction resides in the known potentiating effect of elevated intramuscular temperature. Alternatively, one might postulate a neurally mediated increase in gain of the stretch servomechanism. The possibility of both mechanisms being operative is not excluded.
对24名正常男性进行了研究，观察三种不同的局部肌肉疲劳性运动对跖屈反应时间和跟腱反射时间的影响。运动条件为每组包含30次最大自主等长收缩（MVC）的跖屈运动，每组MVC之间的休息间隔分别为5秒、10秒或20秒。力量下降幅度在15%至34%MVC之间。对疲劳模式的趋势分析表明，三次正交多项式方程足以描述所有条件下MVC下降的情况。疲劳运动后，简单视觉反应时间（跖屈）及其两个组成部分，即运动前时间和运动时间，与运动前相比没有变化。然而，跟腱反射时间明显增加，表现为总反射时间、收缩时间和半松弛时间缩短。这些结果可能表明在三种运动任务中，即MVC、自主反应和跟腱反射中，运动单位的疲劳存在差异。反射收缩增强的一个合理原因是已知的肌肉内温度升高的增强作用。或者，也可以假定是神经介导的牵张伺服机制增益增加。两种机制都起作用的可能性也不能排除。
