Physiological Effects of Exercise on Post-menopausal Osteoporotic Women

Abstract

Summary Background The aim of this study was to investigate the effects of a class-based exercise programme consisting of aerobic, strength and flexibility components on previously diagnosed post-menopausal osteoporotic women. It is hypothesised that improvements in some physiological variables could result in these women being less likely to fall and thereby incur fractures. Methods Thirty subjects volunteered to take part in the study. Sixteen exercisers and 14 control subjects completed all the measurements. The exercise group attended group sessions twice weekly and carried out one further exercise session at home. The subjects exercised at approximately 60–75% of their age-predicted maximum heart rate. The variables measured before and after intervention were body mass, predicted percentage body fat, sub-maximal steady state heart rate, predicted VO 2 max, flexibility, balance and quadriceps muscle strength. Results The exercise group showed significant improvements (expressed in 95% confidence intervals of the exercisers' additional improvement over that for controls) compared to the controls in percentage body fat (0.7, 2.1), predicted VO 2 max (3.4, 8.5) ml kg −1 min −1 , flexibility (4.3, 9.8) cm and functional reach (0.01, 6.1) cm as well as isokinetic strength, both at 2.09 rad s −1 (1.1, 5.2) newton metres and at 1.05 rad s −1 (0.9, 6.3) newton metres, and isometric strength of the quadriceps muscle group (5.1, 13.6) newton metres. Conclusions Following a 12-week exercise intervention, health related fitness benefits were demonstrated for this population. These benefits were achieved through an easily organised physiotherapy class which could be copied in other locations. It cannot be hypothesised that the physiological improvements in the exercise group will lead to a reduced risk of osteoporosis. However, the fitness gains could result in reductions in falls and consequently fracture rates in post-menopausal osteoporotic women.