Ten years ago, a clinical trial ended, which had been examining the effects of a walking intervention on bone density in 229 post-menopausal women in Pittsburgh. At the end of the 2.5 year study, the intervention women were found to be more active than the control women based upon activity surveys and activity monitors. A milestone of this clinical trial was that it achieved record-setting compliance with 80% of the intervention women reporting a minimum weekly walking estimate of 5 miles averaged over the 2.5 years of the clinical trial. The women who participated in the original clinical trial were re-contacted in 1995 and interviewed by phone to obtain their current activity levels and health status; 90% of the original participants were successfully traced. Based upon the reported activity data, the intervention women appeared to have maintained higher physical activity levels compared to the control women. In addition, there was a striking difference noted between the two randomized groups in the 10-year incidence of reported heart disease. Two women in the intervention group reported heart disease compared to 11 control women (relative risk=0.18). The purpose of this current application is to contact these women again to validate the large differences in incidence of coronary heart disease reported between the two randomized groups and to determine if the two intervention groups differ by objective measures of physical activity, coronary heart disease risk factors and bone density. Heart disease will be validated through an evaluation of hospital reports, physician contacts and extensive medical histories. Physical activity monitors will be utilized in this study to obtain an objective measure of current activity. Bone density (AP lumbar spine, proximal femur and whole-body) and whole-body soft-tissue composition will be determined by dual energy x-ray absorptiometry. Ultrasound scanning will be performed to determine the level of atherosclerosis in the carotid arteries. Cardiovascular risk factors such as lipids, total body fat, fasting insulin and glucose concentrations, and resting blood pressure will also be measured and compared between the two groups. The investigators state that the study is designed to address an important area of public health and would be the first clinical trial to investigate the long term effects of moderate intensity exercise in older women.