This study examined the relationship between medical advice to engage in physical activity with type of demand required by physical activity and demographic variables. A cross-sectional study was developed, featuring a questionnaire on physicians' advice, and type of demand. The questionnaire was completed by a probability and nationwide sample of older adults in Spain (n = 933, M = 74.1, range 65-93), randomly selected using multistage sampling. More physically active older adults have, more often than the less active, received physicians' advice to engage in physical activity. There is a significant relationship between medical advice and type of demand (p < .01) and age (p < .05). However, no relationship was found between physician medical advice and gender, social class, or income. Physicians can effectively promote physical activity among sedentary older adults through appropriate advice. Consequently, health authorities should promote physicians' advising older patients to pursue physical activity.