Abstract:

BACKGROUND: Studies demonstrated that the combination of sports and estrogen play a prevention effects on bone loss of ovariectomized rats, however, there are few reports concerning the effects of sports and selective estrogen receptor modulators (SERMs) on bone metabolism.
OBJECTIVE: To investigate the combined efforts of swimming and SERMs on bone metabolism of ovariectomized rats by comparing biomechanical index.
METHODS: Totally 50 female SD rats were randomly divided into 5 groups. All rats were made ovariectomized models except that in the sham-surgery group. Swimming exercise and (or) SERMs raloxifene were performed on rats in the exercise, medicine, and exercise + medicine groups. The changes of blood biochemical index were compared among groups at 8 weeks after operation. 
RESULTS AND CONCLUSION: Exercise intervention at the early stage of ovariotomy could inhibit the rapid weight increase. Compared with model group, the serum phosphorus and alkaline phosphatase levels in the exercise, medicine, and exercise + medicine groups were obviously increased (P < 0.05 or P < 0.01), tartrate-resistant acid phosphatase levels were dramatically decreased (P < 0.05), especially in the exercise + medicine group, but the difference had no significant (P > 0.05). The results demonstrated that, swimming exercise and (or) SERMs can improve blood biochemical index in bone metabolism, delay bone loss, and inhibit high conversion rate of bone metabolism. The combination of these two interventions exhibit optimal effects.