The aim of this study was to examine physiological, perceptual, and affective responses during self-paced walking for three age groups. 66 adult women were assigned into three groups by age: 20-25 yr. (n=22), 30-35 yr. (n=22), and 40-45 yr. (n=22). Each participant completed a maximal exercise test and a 20-min. bout of walking at a self-selected pace. The preferred walking speed was similar for all age groups, whereas physiological responses relative to maximal and ventilatory threshold values were greater in the 40-45 yr. group than the other two groups. Nevertheless, perceptual and affective responses were similar for all age groups. These findings suggest that physiological responses, but not perceptual and affective responses, of sedentary women are associated with age during walking at a self-selected pace.