In brief: Distance runners, sprinters, jumpers, and weightmen in track and field offer advantages for studying the effects of physical exertion on selected cardiovascular parameters because they undertake a variety of training programs. Fifty-six athletes and 40 controls were tested for percent body fat, maximal oxygen consumption, and plasma lipids before and after a seven-month training season. Sprinters had lower percent body fat and distance runners had higher vo2max values than the other groups, but all groups had low plasma lipids. However, a season of training did not beneficially change these variables-probably because the athletes were already fit.