EFFECTS OF PHYSICAL TRAINING ON THE MECHANICAL RESISTANCE OF RAT FEMUR PROXIMAL THIRDS

Objective: To analyze the mechanical behavior of rat femur proximal thirds submitted to chronic aerobic and resistance training. Methods: Male Wistar rats (80 days of age, weighing 300 to 350 g) were divided into 3 groups (n=8 per group): control (CO), aerobic training (AT) and resistance training (RT). At the end of the training, the animals were euthanized and the right femur was collected. Flexion-compression tests were carried out to analyze the mechanical behavior of the femurs. Results: The resistance training promoted a significant reduction in maximum force (F(max)) of the femur. However, it also promoted a relevant increase (23.7%), though without statistical significance, in maximum force deformation (DF(max)). The aerobic training did not affect maximum force, however, it caused a considerable reduction in DF(max) (26.6%), though this was also not statistically significant. Conclusions: The results show that resistance and aerobic training promoted a reduction in the F(max) and DF(max) respectively. The data showed a different response of both physical training models on the mechanical properties of the rat femurs.