This study was designed to determine how aging and individual activity patterns affect females' response to maximal exercise. Two treadmill tests for maximal aerobic power (Vo2 max) were administered to 109 females, ages 10 to 68. Subjects were classified as above or below age group means for Vo2 max reported for Scandinavian and Canadian females. Aging effects on cardiovascular and respiratory variables were minimal within each group until age 50, although there was a significant linear decrement in Vo2 max (L/min) with increasing age for the low fitness group. VE max, oxygen debt, postexercise blood lactate, vital capacity, and maximal breathing capacity were also lower for these women. Aging patterns were similar for both groups for Vo2 max ml/kg times min- minus 1 and ml/kg (LBM) times min- minus 1. Responses to an Activity Questionnaire suggested that habitual levels of activity rather than age per se determines levels of Vo2 max for women in the 20-49 age range.
Drinkwater et al. (1975) studied this question.