Last update:
15-Jul-2011

Osteoporosis is the most common metabolic bone disease and postmenopausal women comprise the group at highest risk. During the first five to ten years after the beginning of menopause, rapid loss of bone density amounting to 2−3% annually is observed in women. Osteoporosis can be caused by multiple factors, the major of which are hormonal, metabolic, dietary and mechanical, including the lack of exercise and physical activity. Bone is not an inactive tissue but responds to pressure, as do other tissues of the body. Each change in the form or function of the bone leads to changes in its internal architecture and exterior configuration, so that the skeleton maintains such a level of structural integrity as to support the daily functional activity of the individual. Bone, like muscle, develops hypertrophy in response to a mechanical stimulus (e.g., strain caused by exercise), and conversely is weakened by immobility. Although limited physical activity has been recognized as an additional factor in the etiology of osteoporosis, the contribution of exercise to the management of the condition has not been clarified completely. Initially, aerobic exercise, and mainly walking, was proposed to postmenopausal women. The results, however, were not those initially expected, and researchers then tried to increase the vertical strain with exercises of higher intensity. They also included specialized resistance exercise programs, to promote deceleration of bone deconstruction and maintenance or even increase of bone density in postmenopausal women. The last decade, the combination of strength and aerobic forms of exercise has been proposed as ideal for bone health, even though it has not been extensively investigated. This review studies the recommended exercise protocols and evaluates their effectiveness and possible contribution to the prevention of osteoporosis and their role in the deceleration of the bone deconstruction that occurs at menopause.

Key words: Aerobic exercise, Bone mineral density, Postmenopause, Resistance exercise.