Sustainability of exercise-induced increases in bone density and skeletal structure.

BACKGROUND: The prevalence of osteoporosis with related fragility fractures has increased during the last decades. As physical activity influences the skeleton in a beneficial way, exercise may hypothetically be used as a prophylactic tool against osteoporosis. OBJECTIVE: This review evaluates if exercise-induced skeletal benefits achieved during growth remain in a long-term perspective. DESIGN: PUBLICATIONS WITHIN THE FIELD WERE SEARCHED THROUGH MEDLINE (PUBMED) USING THE SEARCH WORDS: exercise, physical activity, bone mass, bone mineral content (BMC), bone mineral density (BMD) and skeletal structure. We based our inferences on publications with the highest level of evidence, particularly randomised controlled trials (RCT). RESULTS: Benefits in BMD achieved by exercise during growth seem to be eroded at retirement, but benefits in skeletal structure may possibly be retained in a longer perspective. Recreational exercise seems to at least partially maintain exercise-induced skeletal benefits achieved during growth. CONCLUSIONS: Exercise during growth may be followed by long-term beneficial skeletal effects, which could possibly reduce the incidence of fractures. Exercise during adulthood seems to partly preserve these benefits and reduce the age-related bone loss.