The physical stress on the rescuer performing cardiopulmonary resuscitation (CPR) was assessed utilizing the ECG, rate pressure product (RPP), and total body oxygen consumption (Vo2). Six healthy physicians served as rescuers. Only a submaximal physical effort was required to perform good CPR, as demonstrated by the heart rate and Vo2 changes. However, the effect was enough to generate a mean rescuer RPP approaching 20,000, with 2 of the rescuers well over 20,000. These data suggest that CPR might elicit ischemic symptoms in a rescuer with coronary artery disease.