Effects of 12 Weeks Resistance Exercise on Blood Testosterone, DHT and Bone-Related Metabolism in Orchiectomized Rats

Abstract

PURPOSE Osteoporosis is a public health problem that requires constant attention in an aging society. This study examines the effects of 12 weeks of resistance training on serum sex steroid hormone and bone metabolism factors in orchiectomized rats. METHODS A total of 30 male Sprague-Dawley (20 week-old) rats divided into three groups; (1) CON (normal-control, n=10), (2) ORX-CON (orchiectomized-control, n=10), (3) ORX-RE (orchiectomized-resistance exercise, n=10). The resistance training performed ladder climbing (8 repetitions, three days per week for 12 weeks) starting 1 week after surgery. RESULTS The investigation revealed that compared to the CON group, the ORX-CON group showed significantly lower levels of testosterone, dihydrotestosterone (DHT), grip strength, bone mineral density (BMD) and breaking force, but much higher levels of osteocalcin and CTx-1. The ORX-RE group showed increased grip strength, hormones (testosterone and DHT), osteocalcin, and BMD compared to ORX-CON group. CONCLUSIONS These findings suggest that resistance exercise training may be an intervention strategy for prevention osteoporosis and fracture in male aging process.

Keywords

• resistance exercise
• testosterone
• osteoporosis
• bone metabolism
• orchiectomized rat