Effects of exercise on bone mineral content in postmenopausal women

The purpose of this study was to test the effects of a 10-month exercise program on bone mineral content (BMC) and bone mineral content/bone width (BMC/BW) of postmenopausal women. Thirty-one women (ages 57-83) completed either a general aerobics exercise program (n = 10), a general aerobics plus upper body weight training exercise program (n = 10), or served as nonexercising control subjects (n = 11). Average compliance rates for the exercise subjects ranged from 72 to 80%. All subjects were pre- and posttested for BMC and BMC/BW in the radius of the nondominant forearm. ANOVA results indicated that there were significant differences between the exercise and control subjects in the amount of change in BMC and in BMC/BW (p less than .05) during the course of the study. The exercise subjects experienced mean increases of 1.38% and 1.33% in BMC and BMC/BW, respectively, whereas the control group had decreases of 2.50% and 2.58%. No significant differences were found for subjects in the two types of exercise programs, suggesting that the effects of exercise relative to maintenance of bone density may be general as well as localized.