The decline in aerobic capacity does not appear to be linear across age. To explore this relationship, we examined the maximal cardiorespiratory response of 251 postmenopausal women to 6 months of exercise training: control (no exercise), or exercise at 4, 8, or 12 kcal/kg/week (KKW). Exercise intensity was set at a heart rate associated with 50% of peak VO(2peak) and women were stratified by age into three groups: <55 years, 55-59 years, >60 years. Differences in outcomes among groups were tested by ANOVA and the results were presented as adjusted least squares means with confidence intervals. At baseline participants who were >60 years had a lower VO(2peak) than those <55 years [mean (SD) 1.44 (0.24) vs. 1.20 (0.20) L/min, P < 0.04). Following exercise training, we observed an attenuated training response due to age within the 8 and 12 KKW groups (both, P for trend 0.001). For the 8 KKW group, changes in VO(2peak) were [mean, (95% CI)]: <55 years [0.18 (0.12, 0.24) L/min], <55 years, 55-59 years [0.08 (0.02, 0.15) L/min], and >60 years [0.02 (-0.03, 0.08)]. For 12 KKW group, the changes were: <55 years [0.19 (0.15, 0.24) L/min], 55-59 years [0.13 (0.08, 0.18) L/min], and >60 years [0.05 (-0.01, 0.10)]. Our data show that despite similar exercise intensities, age plays a significant role in the maximal cardiorespiratory response to exercise training regardless of training volume in women who have completed menopause.