Out of 636 patients with acute myocardial infarction (AMI) admitted to our institution, 183 patients enrolled in our non-supervised home exercise program immediately after their discharge from the hospital. The first 40 patients were randomized to control and training group, while the remaining 143 patients were included in the training group. Before and after the trial, all patients underwent cardiopulmonary exercise testing; submaximal graded treadmill exercise test with the application of expiratory gas analysis. In the training group, patients performed 2 km walk-jog exercise everyday for 1 month, keeping their heart rate (HR) at 90-100% of that in the anaerobic threshold. HR during exercise was monitored by patients themselves, using HR-meter. The anaerobic threshold significantly increased in the training group; while control group had no significant changes. VO2 and HR significantly increased at the same Borg's indices. Psychological improvement was also obtained in the training group compared to control group. It is concluded that non-supervised home exercise program is effective and easily applicable in the convalescent phase of AMI.