THE EFFECT OF WEIGHTED EXERCISES ON BONE MINERAL DENSITY IN POST MENOPAUSAL WOMEN.

Abstract

Purpose: Osteoporosis is both preventable and treatable with therapeutic exercise playing an important role along with adequate nutrition and medication if required. Physical therapy interventions for women with osteoporosis have generally emphasized postural awareness, aerobic conditioning, and balance training as preventative measures and have paid scant attention to weight training exercises to stimulate bone formation. The purpose of this systematic review was to determine if exercise programs utilizing weights are an effective method to maintain or increase the bone mineral density (BMD) in postmenopausal women to prevent or decrease the sequelae associated with osteoporosis. Description: A computerized search of the MEDLINE, PEDro, and Science Citation databases was conducted for the years 1990 through February 2005. The search was performed using English language-only keyword searches using MESH terms ‘osteoporosis’, ‘postmenopausal’, exercise’, weight training’, and bone mineral density’. Inclusion criteria consisted of 1) randomized controlled trials with more than 15 participants, 2) self-selected group trials, 3) less than a 35% drop out rate, 4) post-menopausal women between the ages of 40 to 80 years old, 5) DEXA scan as the method of determining bone mineral density, and 6) incorporation of weighted or resistive exercises as a therapeutic intervention to promote osteogenesis. A total of 20 articles were critically evaluated for the quality of an intervention study using the criteria developed by MacDermid.18 These twenty articles were identified and reviewed with respect to specific exercise programs including their duration, frequency, and intensity and their effect on the BMD at the lumbar spine, femoral neck, femoral trochanter, lumbar spine, and distal radius. The articles were critically evaluated. Summary of Use: Our review revealed evidence to support the effectiveness of weight training exercises to increase bone mineral density in post-menopausal women. The increases in BMD were site-specific and required high loading with a training intensity of 70% to 90% of 1 RM for 8-12 repetitions of 2 to 3 sets of over one year duration to promote osteogenic changes. Most of the studies indicated that exercises that were effective in maintaining or increasing BMD had a combination of weight training with ground force exercises such as the use of a weighted vest and jumping combined with resistive exercises. Importance to Members: Weighted exercises can help in maintaining bone mineral density in post-menopausal women and increasing bone density of the spine and hip in women with osteopenia and osteoporosis. The exercise program must be incorporated into a lifestyle change and be lifelong due to the chronic nature of bone loss in older women. Physical therapists need to challenge their patient's with postmenopausal osteopenia and osteoporosis to the point of osteogenesis. For these patients there should be a longer intervention with follow-up to review and modify the treatment program to stimulate bone formation.