The decline in physical and mental ability often associated with increasing age in adults has both social and economic implications that affect most nations. Hence, the maintenance of functional capacity and independence of the older person are beneficial both for the individual and society alike. One way to enhance functioning in old age is physical exercise. However, few methods exist that enable older people to monitor and regulate exercise intensity without using expensive apparatus. Utilizing the individual's subjective feeling of perceived exertion through the use of a simple rating scale is an approach that differs markedly from those previously employed. The present study used the ratings of perceived exertion (RPE) scale to induce different exercise intensities in groups of older women. Walking was chosen as the type of exercise since most older women are unfamiliar with, or afraid to engage in, other types of physical exercise such as bicycling or running. Results indicated that physical exercise capacity increased after 3 months of regular low-intensity walking in the exercise groups but not in nonexercising controls. Furthermore, these changes were accompanied by improved digit span performance. In conclusion, this study has shown that the RPE scale may be used for exercise regulation and that older women would seem to be able to use the scale to monitor and regulate their exercise intensity in an outdoor environment in much the same way as younger individuals.