Exercise: A Prevention and Treatment for Osteoporosis and Injurious Falls in the Older Adult

Abstract

Osteoporosis is a major public health problem in persons over the age of 65, and it leads to approximately 250,000 hip fractures per year. Contributing risk factors for osteoporosis and hip fractures in the aging population include insufficient nutrient intake, inadequate dietary calcium, muscular weakness, decreased physical activity, and changes in hormonal homeostasis. Physical activity especially plays an important role in the prevention of falls and fractures. Physically active older adults with greater muscular strength experience fewer and less injurious falls than older people who are inactive. The effects of physical activity on bone strength and metabolism have only recently been investigated. When bone is mechanically stimulated, the cells respond by producing many local hormones and growth factors, including prostaglandin E, (PGE$), a mediator of bone modeling and remodeling. Current research continues to show that physical activity significantly affects the geometry and architecture of bone as well as increasing bone mineral density, all of which contribute to an increase in bone strength.Key Words: physical activity, osteoporosis, bone, mechanical loading Osteoporosis and fractures resulting from falls are a major public health hazard for older adults. Evidence is beginning to emerge that physical exercise can both strengthen bone integrity and reduce risk factors for falls (such as muscle weakness, poor balance, and slow gait velocity). This review will discuss current knowledge in the following areas: (a) general bone metabolism, (b) prevalence of and risk factors for falls and fractures, (c) the effects of exercise on risk factors for falls and fractures, especially bone mineral density, and (d) cellular hypotheses for the mechanisms of the bone response to exercise. Overview of Bone MetabolismThe skeleton not only provides structural support but also serves as a mineral reservoir. Skeletal architecture, geometry, and bone mineral content respond to hormonal and mechanical homeostatic mechanisms through the processes of The authors are with the

Determinants of Bone Mineral Density in Older Men and Women: Body Composition as Mediator

“…This is in agreement with several observational (53,54) and intervention studies. This is in agreement with several observational (53,54) and intervention studies.…”

“…We found a protective effect of physical activity on total hip BMD in men and women. This is in agreement with several observational (53,54) and intervention studies. (8,9,55) Men who were current smokers had lower total hip BMD, which agrees with the results of prior studies.…”

“…A positive relationship between walking activity and FM ( Table 2) may indicate that active elderly people have a higher body weight than inactive elderly people. (54,73) Our study has several weaknesses. (72) The findings are in line with the idea that the effect of physical activity depends on the extent to which mechanical loading is applied to the bones.…”

Impact of a 12‐Month Exercise Program on the Physical and Psychological Health of Osteopenic Women

“…Several such studies can be found in the literature 8 . These have been largely restricted to healthy postmenopausal women who present no risk factor for osteoporosis 9 . To our knowledge, no randomized controlled trial has ever been conducted to estimate the effectiveness of physical activity in women with bone mass below a preset threshold.…”

Increased Prevalence of Fall Risk Factors in Older People following Hip Fracture

“…It has been estimated that at least 90% of hip fractures result from a fall [10], and there is evidence that fall-related risk factors such as impaired lower limb strength, postural sway, reaction time and walking speed are also risk factors for hip fracture [11]. There is also evidence that muscle strength [12], postural sway and walking speed [13] are further impaired following hip fracture.…”