In brief: Ten masters female long-distance runners (mean age 43.8 years) were assessed for body composition and cardiovascular endurance. The mean body fat was 18.3%, which is approximately 40% of the value for a control group of sedentary women. The only women exhibiting lower values for Percent body fat were much younger elite athletes. VO2max averaged 43.41 ml·kg−1min−1, which is 25% higher than that of normal women of comparative ages. The question of whether a lifetime of endurance training can offset the age- related decrease in Vo2max is still unknown, but the increased interest in masters competition may provide the data to answer this question.