Effects of physical training on bone mineral density in fertile women with idiopathic osteoporosis.

The aim of this study was to investigate whether moderate physical training can improve the bone mineral density (BMD) in women with idiopathic osteoporosis. Ten pre-menopausal women aged 24-44 years diagnosed with idiopathic osteoporosis were included in the study. The physical training program consisted of three fast 30-min walks plus one or two sessions of 1-h training per week during 1 year at a training centre separate from the hospital. All patients were given supplements of vitamin D and calcium. Bone mineral density was measured in the femoral neck area and the lumbar spine by dual energy X-ray absorptiometry. The measurements were performed at baseline and after 12 months of training and compared with the measurements at the time of diagnosis, 1-3 years before the study. Eight women fulfilled the 12-month training period, and their mean (SD) BMD at start was 0.88 (0.08) g/cm(2) in the spine and 0.76 (0.13) g/cm(2) in the femoral neck. The mean spine BMD increase was 0.031 g/cm(2) (3.5%) after 1 year of training, which was significant (Wilcoxon's non-parametric test, p = 0.018). The mean increment in BMD in the femoral neck was insignificant, 0.007 g/cm(2) (0.9%) after the intervention (p = 0.74). However, the bone loss during the 1- to 3-year period from diagnosis to study start was, on average, 0.045 g/cm(2) or 5.0% in the femoral neck (p = 0.042), thus indicating a positive indirect effect of the intervention. There is no evidence-based therapy for women with idiopathic osteoporosis. It is therefore of importance to elucidate the impact of moderate physical activity in this group of patients. A 1-year training program was sufficient to induce a small but significant change in the spine BMD.