One hundred and twenty asymptomatic patients underwent a submaximal treadmill exercise 2-3 weeks after an acute myocardial infarction. These patients were subsequently followed from 15 to 54 months (average 2 years). Coronary events (cardiac death or angina) occurred in 14% of the patients with normal response, in 55% of those with ischemic response and in 12% of those with abnormal but non-ischemic response. The incidence of coronary events in patients with ischemic response is significantly higher than in the other two groups. However, among the patients who had a normal response, one out of seven suffered from a coronary event during the follow-up period. More than 25% of our patients with an ischemic response to the early exercise testing showed a non-ischemic response during a second one. On the other hand, more than 25% of our patients with normal early exercise test had an ischemic response when the test was performed at the end the follow-up period. Submaximal exercise testing of asymptomatic patients early after an acute myocardial infarction does not seem to be predictive of future coronary events and its long-term reproducibility is poor.