Combination Therapy Using Exercise and Pharmaceutical Agents to Optimize Bone Health

Abstract

Aging is associated with a reduction in bone strength and resultant increase in low trauma fractures. These so-called osteoporotic fractures represent a prominent and growing societal problem. To reduce the individual and societal cost of osteoporosis there is a need for efficacious interventions. Two frequently prescribed interventions are load-bearing exercise and pharmaceutical agents. These modalities have similar, yet somewhat contrasting influences on the underlying processes responsible for bone health. Exercise affects both osteoblastic bone formation and osteoclastic bone resorption to have both anabolic and anti-resorptive effects. Pharmaceutical agents target these processes also; however, they are typically specific to one process or the other. For instance, anti-resorptive agents such as bisphosphonates target osteoclast-mediated bone resorption, whereas anabolic agents such as intermittent parathyroid hormone (PTH) target osteoblast-mediated bone formation. In light of the similar targets of both exercise and pharmaceutical agents, questions have been raised of whether combining the two modalities may result in greater enhancements in bone health than with their isolated introduction. This article discusses the tissue-level processes regulating bone health, mechanisms of action of exercise and pharmaceutical agents, and rationale and current evidence for combined exercise and pharmaceutical intervention for optimizing bone health.