The effects of dynamic exercise training on hemodynamic and catecholamine responses to rest, and to exercise and localized cold (singly and in combination) were studied in patients with coronary artery disease. Patients receiving beta-blocking medications and those not receiving beta blockers responded similarly. Myocardial oxygen demand (MVO2) was estimated by the rate-pressure product. Training caused a 25% increase in maximal oxygen uptake; a 15% decrease in resting MVO2; a decrease in MVO2during acute localized cold exposure alone (16%), in standard submaximal exercise alone (16%), or in the two in combination (19%); and unaltered resting and relative exercise urinary catecholamine excretions, although absolute exercise intensity had nearly doubled. We suggest that this reduction in MVO2may contribute to clinical improvement in patients with cardiac disease who engage in physical activity in cold environments.