Maintenance of BMD in older male runners is independent of changes in training volume or VO(2)peak.

Abstract

The results of several recent research studies have questioned the benefit of chronic running in reducing the risk of developing osteoporosis. These negative conclusions are based upon the findings that runners, in general, are not different from controls with regard to their bone mineral density (BMD). This has led one to speculate that the value of weight-bearing exercise might be related to its ability to maintain bone mass or, perhaps, decrease the expected rates of loss. We examined a group of 54 male master athletes ranging in age from 40 to 80 years longitudinally over a 5- to 7-year intervening period. Physiological parameters included VO(2)peak, body composition, bone density, and running performance. Medical histories and training records were obtained via questionnaire. Over the average 4.6 years between tests one and two, significant increases in body weight and lean body mass were observed. Aerobic fitness declined, as did weekly mileage and 5K and 10K performance times. Bone mineral density was lower in the whole body but not in the hip or the spine. Finally, we report no significant relationship between the change in training volume, change in body weight or lean mass, and change in aerobic capacity with changes in BMD. Hip and spine BMD are maintained over a 4- to 5-year period in master runners. Furthermore, changes in bone density or content are not sensitive to moderate changes in training volumes. We conclude that bone density can be maintained by running in older active men. These findings suggest that if a minimal threshold of mileage is required, the level is certainly below the average mileage of master runners.