[Adaptation of motor nerve fibers to physical activity].
The effects induced by training on the H-reflex of soleus and lateral gastrocnemius muscles have been studied on 19 adult male volunteers; out of these, 10 were non-trained subjects and the remaining 9 were top level athletes engaged in sports requiring very rapid and intense contractions (sprinters and volley-ball players). It has been observed that the latency of the M response is significantly higher in the athletes than in the non-trained subjects. Instead, no significant differences were observed between these two groups, concerning the latency of H response. The increase of M response latency is likely due to a decrease of nerve conduction velocity in the terminal part of motor fibers. The possibility that this conduction speed decrease could be dependent on sprouting and/or terminal branching growth of the motor nerve ending is discussed.
Perciavalle
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Istituto di Fisiologia umana dell'Università di Catania.
Casabona
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A
Polizzi
M C
MC
D000293:Adolescent; D000328:Adult; D006181:H-Reflex / Q000502:physiology*; D006801:Humans; D008297:Male; D009046:Motor Neurons / Q000502:physiology*; D009431:Neural Conduction; D005082:Physical Exertion; D011930:Reaction Time; D013177:Sports
Adattamento delle fibre nervose motorie all'attività fisica.