Early women's health research on endurance exercise training and cardiovascular aging at the University of Colorado Boulder using the masters athlete model.

As male physiology was historically viewed as the "norm" and data on females were considered difficult to interpret, little information regarding the effects of regular exercise on women's health over the lifespan was available leading into the 1990s. In 1993, we initiated research at the University of Colorado Boulder to determine the effects of endurance exercise training on healthy cardiovascular aging in women. To do so, we used a "masters athlete model" in which midlife and older female distance runners were compared with their healthy, but nonexercising peers, as well as young adult women. The masters runners (∼50-70 yr, mostly postmenopausal) had a maximal oxygen consumption (V̇o2max) almost twice that of nonexercising postmenopausal women, in part due to a larger total blood volume. The masters runners showed stable body mass with age/menopause and exhibited much smaller age-related differences in total body fatness and abdominal adiposity than nonexercising women, related in part to preserved resting metabolic rate. The masters runners maintained a healthier overall systolic blood pressure profile and showed smaller differences in large elastic artery (aorta and carotid arteries) stiffness with age/menopause compared with nonexercising women. In contrast to nonexercising women, circulating coagulation and fibrinolytic activity was well-preserved with age/menopause in the masters runners. Masters runners also maintained greater heart rate variability, more favorable regulation of plasma glucose and insulin, and a superior plasma lipid-lipoprotein profile compared with nonexercising postmenopausal women. In contrast to males, female masters athletes did not demonstrate greater vascular endothelial function than their nonexercising peers. Collectively, this work represented the first systematic research conducted on the benefits of endurance exercise training on optimal cardiovascular function and health with age/menopause in women using the masters athlete model.