The purpose of this study was to determine whether 12 months of intense endurance exercise training can induce an increase in left ventricular volume and in stroke work during exercise in patients with coronary artery disease. Eleven male patients were studied. With training, mean maximal oxygen uptake capacity (V̇O2max) increased 39%, from 1.85 ± 0.36 to 2.57 ± 0.43 l/min. Stroke volume during upright exercise that required 35-65% of V̇O2max was 18% higher after training. At the same percentage of V̇O2max, mean blood pressure was the same before and after training; as a result, left ventricular stroke work (mean blood pressure x stroke volume) increased 18% (p <0.01). These findings suggest that in patients with coronary artery disease, prolonged, intense training induces an increase in stroke volume, and this is a result of cardiac rather than peripheral adaptations.