We compared conditioning effects of a supervised exercise program in 100 elderly and younger patients with a recent coronary event. Twenty-one patients were greater than or equal to 62 years of age (mean, 65 years) and 79 were less than or equal to 61 years of age (mean, 48.7 years). While the elderly patients attained a lower peak exercise intensity on entry and on completion of the exercise protocol, they obtained a similar relative training benefit as the younger patients. Peak exercise intensity increased 68% in each group and submaximal (five METS) heart rate-blood pressure product decreased 27% in the older patients and 26% in the younger patients. Rate of entry into our program was substantially lower in the elderly patient group, 19% v 57% in younger patients (P less than 0.001) despite a similar inhospital recruiting effort. Thus, although elderly coronary patients obtain similar training benefits as younger patients, they are less likely to participate in a program designed to decrease cardiac disability.