ABSTRACT
Objective To investigate the effect of different loads of swimming on change of bone metabolism of the aged male mice. Methods Forty Kunming strain male mice aged twelve months were randomly divided into five groups: thirty minute group, sixty minute group, sixty minute plus load group, experimental control group and sedentary control group. Eight male mice of two months old were recruited and served as the young sedentary controls. At the end of the 8 week, training period, all mice were sacrificed, the femur and thoracic vertebra were sampled for determining content of hydroxyproline, and serum testosterone, estradiol, osteocalcin, alkaline phosphatase and calcium were tested. Results After 8 weeks of swimming training, serum testosterone and estradiol levels and the content of hydroxyproline in the femur were significantly increased ( P