The effects of 9 months of aerobic exercise on aerobic work capacity (physical fitness), coronary heart disease risk factors, and sexuality were studied in 78 sedentary but healthy men (mean age, 48 years). The men exercised in supervised groups 60 min per day, 3.5 days per week on average. Peak sustained exercise intensity was targeted at 75-80% of maximum aerobic working capacity. A control group of 17 men (mean age, 44 years) participated in organized walking at a moderate pace 60 min per day, 4.1 days per week on average. Each subject maintained a daily diary of exercise, diet, smoking, and sexuality during the first and last months of the program. Beneficial effects of chronic, vigorous exercise on fitness and coronary heart disease risk factors were obtained in close agreement with prior studies. Analysis of diary entries revealed significantly greater sexuality enhancements in the exercise group (frequency of various intimate activities, reliability of adequate functioning during sex, percentage of satisfying orgasms, etc.). Moreover, the degree of sexuality enhancement among exercisers was correlated with the degree of their individual improvement in fitness.