Mr. Li is 53 years old, is a state-owned enterprise employees, usually more social, irregular life, smoking for decades. Usually his body is still strong, but one day in the busy work suddenly developed an unbearable pain in the precordial region, accompanied by sweating profusely. Colleagues took him to the hospital in time and diagnosed him with “acute anterior myocardial infarction”, the hospital promptly rescued and opened the infarcted vessel and put a heart stent. A week later, Mr. Li was successfully discharged from the hospital. However, this experience of survival made Mr. Li palpitated and suffered from “exercise phobia” after discharge. He thought he was a patient with a myocardial infarction, although he received timely treatment, but after all, his heart had already been infarcted, the injured heart can withstand the test of exercise? So Mr. Li was discharged from the hospital to live quite carefully, taking regular medication, but also deliberately for the early retirement of major diseases, usually at home in bed, rest and recuperation is the main. A month later, Mr. Li often felt chest tightness, tingling sensation in the precordial area, anxiety about any physical discomfort, and the appearance of loss of appetite, general weakness, shortness of breath when moving. For this reason, he came to my specialist clinic in the Department of Cardiology of Shanghai Chest Hospital. The electrocardiogram, cardiac ultrasound and serological examination of cardiac function were all in the normal range, and the symptoms caused by revascularization and heart failure were not considered. With my years of experience in cardiac intensive care and long-term follow-up of a large number of myocardial infarction patients, in fact, patients like Mr. Li are very common in my specialist clinic, and many patients have misunderstandings about how to exercise after myocardial infarction. So can I exercise after myocardial infarction? How much exercise is appropriate? In order to prevent cardiovascular disease, in 2013 the ACC/AHA in conjunction with the NHLBI organized an expert group to develop healthy lifestyle guidelines for patients with cardiovascular disease based on a number of clinical evidence in recent years, with the aim of assessing the risk of cardiovascular events, modifying lifestyle, controlling lipids and obesity, etc. Physical activity becomes a prevention of coronary heart disease and post-infarction reinfarction and adverse cardiac events Physical activity has become an important part of the prevention of coronary heart disease and post-infarction reinfarction and adverse cardiac events. Numerous studies have shown that aerobic exercise reduces the risk of developing coronary heart disease and other chronic diseases such as diabetes, thanks to its benefits on lipid, lipoprotein, blood pressure and glucose control. Data from large observational studies show that higher intensity physical activity reduces the incidence of many chronic diseases, including coronary heart disease, and increases life expectancy. And physical activity levels are negatively associated with the incidence of cardiovascular disease. A recent analysis estimated that physical activity reduced the incidence of coronary heart disease by 6% and increased life expectancy by an average of 0.68 years. The mechanism is that physical activity can reduce the incidence of cardiovascular disease by regulating blood lipids and blood pressure. Studies have found that physical activity reduces the incidence of coronary heart disease by a mechanism of action that is related to its antihypertensive effect in about 27%, its lowering of traditional lipid levels in 19%, and its lowering of novel lipid levels in 16%. In general, the recommendation for aerobic exercise in adults with coronary heart disease is 3 to 4 times a week, each lasting an average of 40 minutes, of moderate and higher intensity physical activity. Studies have found that approximately 12 metabolic equivalents of exercise are consumed to affect lipid and blood pressure levels, creating a favorable impact on health, i.e., a minimum of 150 minutes (2 hours and 30 minutes) of moderate-intensity physical activity such as brisk walking per week is required, with more exercise providing more benefit. But should this amount of exercise be achieved for post-myocardial infarction patients? Studies have shown that a moderate amount of progressive physical activity in post-infarction patients can also promote cardiac recovery, reducing the risk of reinfarction and cardiovascular death by 28% in patients with heart attacks. Exercise also helps with mood regulation, and patients with myocardial infarction who are physically active have significantly less depression and anxiety, which helps improve patients’ non-specific symptoms due to emotional factors, such as tingling sensations in the precordial region and chest discomfort. However, exercise for post-infarction patients should be based on the principles of moderation and gradual progress, because excessive and premature exercise may induce the occurrence of heart failure. Moderate and reasonable, gradual exercise can increase cardiovascular reserve capacity, reduce myocardial oxygen consumption, promote the formation of coronary collateral circulation, and increase myocardial capillary density. After exercise, the body catecholamine level is reduced, the ventricular fibrillation threshold is increased, and the risk of arrhythmia and sudden death is reduced. The amount of exercise is indicated by not causing shortness of breath, palpitations, dizziness, etc. If the pulse rate after exercise is greater than 20 times/min at rest and the systolic blood pressure is reduced by more than 15 mmHg, the exercise should be reduced, and if the pulse rate does not increase much, the amount of exercise can be increased appropriately. Some aerobic exercises suitable for heart attack patients include walking, jogging, and tai chi. If there is no adverse reaction after exercise in infarction patients without serious complications, it is recommended to gradually reach the amount of exercise required by the above-mentioned ACC/AHA guidelines after 1-3 months of infarction. After Mr. Li was followed up in my clinic for many times, I gave him detailed instructions on exercise and suggested him to be moderately active and relaxed. Old Li followed the advice, learned tai chi and insisted on going for a walk in the park every morning, gradually increasing the amount of exercise, and after 3 months, all the discomfort symptoms of Mr. Li completely disappeared.