Article

Objective: To investigate the effect of short duration static stretching of denervated and reinnervated muscle using a histochemical study on the soleus muscle of the rat. Design: Prospective randomized trial. Setting: University medical school in Japan. Animals: Fifty-four 8-week-old female Wistar rats with a mean weight +/- standard deviation of 185.8+/-9.9g. Interventions: After a cold injury was applied to the rat right sciatic nerve, the bilateral soleus muscles were maximally stretched in the dorsiflex posture of the ankle joints for 40 minutes a day, 6 times a week (group S). Rats were compared with nonstretched rats (group D) for up to 4 weeks. Main Outcome Measures: Muscle fiber cross-sectional areas, muscle fiber types, and sciatic nerve morphology. Results: No apparent difference in the morphologic changes of the sciatic nerve was found between groups D and S. The mean fiber size progressively declined to a minimum 2 weeks after the injury and reversed in the following weeks. At weeks 1 and 2. The mean type I fiber size in group S was significantly larger than in group D (P<.05). The number ratio of the type 11 to total fibers increased until 3 weeks in group D, whereas the ratio in group S was increased at 2 weeks, and successively decreased. Conclusions: The mechanical stimuli of static stretching could prevent atrophy of the type I fibers in the denervated muscle and affect the reinnervated muscle fiber-type composition.

Langue : ANGLAIS

Identifiant basis : 2003227947