Tonic suppression of the soleus H-reflex during rhythmic movement of the contralateral ankle
نویسندگان
چکیده
[Purpose] We investigated the effect of rhythmic ankle movement on the contralateral soleus H-reflex. The H-reflex was evoked from the right soleus muscle. [Subjects and Methods] Healthy humans rhythmically moved the left ankle (movement condition) or held the left ankle stationary (stationary condition) at one of three positions corresponding to the ankle positions at which the H-reflex was evoked in the movement condition. The background electromyographic amplitude in the right soleus muscle was maintained at 10% of the maximum voluntary contraction level, and that in the right tibialis anterior muscle was matched between the stationary and movement conditions. [Results] The soleus H-reflex was suppressed throughout all phases of contralateral rhythmic ankle movement. [Conclusion] Rhythmic movement of the contralateral joint suppresses the H-reflex in the muscle that is the prime mover of the joint homologous to the rhythmically moving joint. This inhibitory mechanism may be activated during unilateral rhythmic movement to isolate the motor control of the moving ankle from that of the contralateral stationary ankle.
منابع مشابه
Different corticospinal control between discrete and rhythmic movement of the ankle
We investigated differences in corticospinal and spinal control between discrete and rhythmic ankle movements. Motor evoked potentials (MEPs) in the tibialis anterior and soleus muscles and soleus H-reflex were elicited in the middle of the plantar flexion phase during discrete ankle movement or in the initial or later cycles of rhythmic ankle movement. The H-reflex was evoked at an intensity e...
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