The 1987 C. H. McCloy Research Lecture¹ Better Bones and Biodynamics

Abstract

A brief review of the anatomy, physiology and biomechanics of bone is presented. The effects of disuse (casting, denervation, space flight, etc.) are summarized. The result of such extreme inactivity is weaker bones with less mineral. In general, a review of the literature shows that active people, including athletes, have larger, more dense bones than less active people. However, amenorrheic runners who train hard tend to have low mineral content in weight-supporting bones and are more likely to develop stress fractures than non-athletic, normally menstruating women. Longitudinal exercise studies in animals, and more limited investigations in humans, indicate a positive effect of exercise on bone mineral. The dominant arms in tennis players show a greater increase in size and bone mineral compared to the non-dominant arm, and the difference is greater than in non-tennis players.

Key Words:

• bone density
• bone mineral
• exercise
• osteoporosis
• physical activity
• skeleton