Blood lipids, red cell volume, heart volume, dynamic spirometry, electrocardiograms made at rest and during exercise, and maximal oxygen uptake were determined in 29 former athletes 45 to 70 years old. The subjects had been very successful competitors in endurance events before the age of 30, but for at least 10 years preceding this study had been sedentary. Maximal oxygen uptake averaged 40 ml...
