AEROBIC TRAINING PREVIOUS TO NERVE COMPRESSION: MORPHOMETRY ANALYSIS OF MUSCLE IN RATS

Introduction: Sciatica stems from compression of the sciatic nerve and results in pain, paresthesia, decreased muscle strength and hypertrophy. Exercise is recognized in the prevention and rehabilitation of injuries, but when performed in overload, it may increase the risk of injury and subsequent functional deficit. Objective: To evaluate effects of aerobic training prior to an experimental model of sciatic pain concerning morphometric parameters of soleus muscles of rats. Materials and methods: 18 rats were divided into three groups: sham (dip, 30 seconds), regular exercise (swimming, 10 minutes daily) and progressive aerobic training (swimming, progressive time from 10 to 60 minutes daily). After six weeks of exercise, rats were subjected to the experimental model of sciatic pain. On the third day after injury, they were killed and their soleus muscles were dissected, weighed and processed for histological analysis. The analyzed variables were: muscle weight, cross-sectional muscle area and mean diameter of muscle fibers. Results: Statistically significant difference was observed for all groups when compared to control muscle and that submitted to sciatic injury. Intergroup analysis showed no statistically significant difference for any of the variables. Conclusion: Both regular physical exercise and aerobic training had no preventive or aggravating effects on the consequences of functional inactivity after sciatica.