Maintenance of body weight, physical activity and calcium intake helps preserve bone mass in elderly women

This prospective study focused on lifestyle factors and weight maintenance that may modulate the rate of bone loss at the weight-bearing proximal femu r and non-weight-bearing distal radius in elderly women. Altogether 128 wom en of 134 subjects participated in this study with a mean follow-up time 3. 9 years (range 2.9-5.3 years). The initially 60- to 65-year-old subjects we re originally selected by their level of physical activity [high (PA(+)) an d low (PA(-))] and calcium intake [high (Ca+) and low (Ca-)], and the origi nal groups were maintained in this study. Physical fitness and bone mineral content (BMC) decreased significantly at a similar rate in all four study groups without any statistically significant between-group difference. The mean change in the muscle strength of leg extensors was -3.3% (95% CI -5% t o -1.5%) at follow-up when including all individuals. The leg extension str ength was still 9.2% (95% CI 2.7% to 16.1%) better in the PA(+) groups comp ared with PA(-) groups at follow-up. The mean change in the forearm flexion strength was -14% (95% CI -16.5% to -11.3%) at follow-up with no e In the strength level between PA(+) and PA(-) groups. The mean change in the estim ated oxygen uptake was -3.4% (95% CI -5.6% to -1.1%) at follow-up. The PA() groups were still fitter, the between-group difference in the estimated o xygen uptake being 11.9% (95% CI 4.8% to 19.5%). The mean changes in BMC at follow-up were -2.1% (95% CI -3.0% to -1.2%) at the femoral neck, -1.9% (9 5% CI -3.2% to -0.5%) at the trochanter, and -12.4% (95% CI -15.4% to -9.4% ) at the distal radius, indicating mean annual losses of 0.6% (95% CI 0.3% to 0.8%), 0.5% (95% CI 0.1% to 0.8%), and 3.2% (95% CI 2.4% to 4.0%), respe ctively. Decreased body weight was associated with higher bone loss in all measured bone sites. High calcium intake and better preservation of physica l fitness were associated with a smaller decrease in femoral neck BMC.