The impact of a senior dancing program on spinal and peripheral bone mass.

Because activity and regular exercise are important factors to maintain general good health in senior citizens, we investigated whether senior dancing has any effect on peripheral or lumbar bone density. We performed a prospective study over a12-mo period on bone density at a spinal and peripheral measuring site in 28 female senior members (mean age: 67 +/- 2 yr) of a dancing group in Vienna. Lumbar bone mineral density was assessed by quantitative computed tomography (qCT) and radial bone density by single photon absorptiometry of the distal forearm. The mean training time per week was 3.2 +/- 0.8 h. In the entire group of female dancers, no significant effects of dancing on radial or lumbar bone density could be observed. Linear regression analysis showed that the lower the qCT at the beginning of the observation period, the higher was the percentage increase of spinal qCT in the entire group during 12 mo of dancing (r = 0.52, P < 0.0001). For additional evaluation, females were divided into two subgroups, osteoporotic or nonosteoporotic, based on x-rays and lumbar bone mineral density (BMD) as measured by qCT. The group classified as dancers with osteoporosis (group I) showed a significant increase in lumbar bone density, whereas in the group of dancers without signs of osteoporosis (group II), BMD remained unchanged. Additionally, radial bone density did not show any changes in either group. Group I showed a significant correlation between basal spinal BMD and the percentage change of BMD during the observation period (r = 0.7, P < 0.001). Changes of the biochemical parameters were observed in the bone-specific isoenzyme of alkaline phosphatase, a marker of osteoblastic activity, in group I giving additional evidence of increased bone formation.