In brief: Two female masters swimmers, ages 70 and 71, members of the 1980 All-American Masters Swim Team, were compared with sedentary females of the same age and with younger female athletes. They had considerably lower percent body fat than normal sedentary women in their 70s and were well within the range for normal women who are 19 to 25 years old. Their Vo2max values were approximately twice those for normal women in their 70s and comparable to considerably younger nonathletes. These findings show that regular physical training may delay the accumulation of excess fat that accompanies inactivity during aging and may also offset the age-related decline in aerobic power.