Despite advances in the study of exercise for acute myocardial infarction (AMI) patients, few studies on exercise for post-AMI heart rupture patients have been reported. We assessed three cases of heart rupture (of the left ventricular free wall in two cases and of the ventricular septum in one case) in post-AMI patients who underwent three-graded exercise. Two of the three patients were operated on, whereas one patient was managed conservatively for heart rupture. Two of the three cases had also suffered cerebral infarction post-AMI. The exercise program was composed of three grades, slow level walking (grade 1), mild reconditioning and activities of daily living (ADL) exercises (grade 2), and optional endurance training using machines below 75% of predicted maximal heart rate (grade 3). Electrocardiograms and blood pressure were monitored during all exercises. All patients had muscle weakness, poor endurance capacity, as well as low cardiac function (28-47% of left ventricular ejection fraction). Two patients underwent grades 1 and 2 exercise programs, and the other performed grades 1, 2, and 3 exercise programs over a 3- to 10-wk period. We observed improvement in the double product, work capacity, and ADL without congestive heart failure, ischemic attack, or serious arrhythmias. However, the youngest patient, who underwent the grade 3 exercise program, died from a cardiac event 10 mo after onset of AMI. We conclude that post-AMI heart rupture patients should undergo delayed, gradual, low-level graded exercise (4-6 metabolic equivalents), with monitoring of blood pressure and electrocardiograms to improve work capacity, ADL, and the quality of life. However, daily activity and exercise intensity should be promptly supervised for those with severely deteriorated cardiac functions to prevent sudden cardiac event.