With increased interest in fitness and health care, jogging has become more popular as an exercise to promote health. However, sudden cardiac death during sports or exercise has also been reported. Some apparently healthy elderly individuals take up sports for both recreation and health improvement based only on completion of a questionnaire, without undergoing medical evaluation. We report the case of a 66-year-old Japanese man who suddenly died of acute ischemic heart disease during first-time jogging. He collapsed an hour after starting. A trainer promptly started cardiopulmonary resuscitation. An automated external defibrillator (AED) was applied, and defibrillation was attempted once by bystanders. However, he remained in cardiopulmonary arrest until he reached the emergency department, where he was pronounced dead. The autopsy found concentric hypertrophy of the left ventricular wall without fibrosis or degeneration, atherosclerotic changes in the coronary arteries, and severe lung congestion. We diagnosed death from acute myocardial ischemia. We suspect that many healthy elderly individuals have provoked a heart attack by prematurely attempting moderate or vigorous exercise, as in this case. The elderly require comprehensive medical assessment before exercise can be started. Moreover, this case shows that an AED is not always helpful. J. Med. Invest. 64: 184-186, February, 2017