Health-related quality of life was evaluated in relation to endurance exercise over the prior year for 194 previously sedentary, healthy men and women aged 50-65 using a posttest-only design. Three exercise regimens were studied that varied in format (class-based vs home-based) and intensity (higher vs lower). In all regimens, subjects who participated more had better physical health 12 months after program initiation (p values < .05); no differences were observed in general psychological well-being. Extent of participation, rather than format or intensity of exercise, was associated with better physical health in this population.