Voigt M, Chelli F, Frigo C
Center for Sensory-Motor Interaction, Aalborg University, Denmark.
Eur J Appl Physiol Occup Physiol. 1998 Nov;78(6):522-32. doi: 10.1007/s004210050455.
Changes in the excitability of the human triceps surae muscle short latency stretch reflexes were investigated in six male subjects before and after 4 weeks of progressive two-legged hopping training. During the measurements the subjects performed 2-Hz hopping with: preferred contact time (PCT) and short contact time. The following reflex parameters were examined before and after the training period: the soleus muscle (SOL) Hoffmann-reflex (H-reflex) at rest and during hopping, the short latency electromyogram (EMG) components of the movement induced stretch reflex (MSR) in SOL and medial gastrocnemius muscle (MG), and the EMG amplitude of the SOL and MG tendon reflexes (T-reflexes) elicited at rest. The main results can be summarized as follows: the SOL T-reflex had increased by about 28% (P < 0.05) after training while the MG T-reflex was unchanged; the SOL MSR (always evident) and the MG MSR (when observable) did not change in amplitude with training, and before training the SOL H-reflex in both hopping situations was significantly depressed to about 40% of the reference value at standing rest (P < 0.05). After training the H-reflex during PCT hopping was no longer depressed. As the value of the measured mechanical parameters (the total work rate, joint angular velocity and the ankle joint work rate) was unchanged after training in both hopping situations, the reflex changes observed could not be ascribed to changes in the movement pattern. To explain the observed changes, hypotheses of changes in the excitability of the stretch reflex caused by the training were taken into consideration and discussed.
在六名男性受试者中，研究了进行为期4周的渐进式双腿跳跃训练前后，人小腿三头肌短潜伏期牵张反射兴奋性的变化。在测量过程中，受试者以首选接触时间（PCT）和短接触时间进行2赫兹的跳跃。在训练期前后检查了以下反射参数：比目鱼肌（SOL）在静息和跳跃时的霍夫曼反射（H反射）、SOL和内侧腓肠肌（MG）中运动诱发牵张反射（MSR）的短潜伏期肌电图（EMG）成分，以及静息时诱发的SOL和MG腱反射（T反射）的EMG幅度。主要结果总结如下：训练后SOL的T反射增加了约28%（P<0.05），而MG的T反射未改变；SOL的MSR（始终明显）和MG的MSR（可观察到时）的幅度在训练后没有变化，并且在训练前，两种跳跃情况下的SOL H反射均显著降低至站立静息时参考值的约40%（P<0.05）。训练后，PCT跳跃期间的H反射不再降低。由于在两种跳跃情况下训练后测量的力学参数（总工作率、关节角速度和踝关节工作率）的值未改变，因此观察到的反射变化不能归因于运动模式的变化。为了解释观察到的变化，考虑并讨论了由训练引起的牵张反射兴奋性变化的假设。
