Running dyspnea may be due to a variety of reasons, common cardiopulmonary insufficiency, coronary artery stenosis, lack of exercise. 1. Cardiopulmonary insufficiency: it is caused by various cardiopulmonary diseases such as chronic obstructive pulmonary disease, pulmonary fibrosis, pulmonary heart disease, rheumatic heart disease, congenital heart disease, etc. The patients usually have no symptoms, but when running, the amount of exercise increases, and the body’s demand for cardio-vascular blood and oxygen supply increases, which leads to accelerated heart rate and shortness of breath, making the patients feel dyspnea. 2. Coronary artery stenosis: the coronary artery is the blood vessel for the heart, such as the occurrence of stenosis, exercise will occur when the myocardial ischemia leading to dyspnea, and even chest tightness, chest pain. 3. Lack of exercise: these people have poor cardiorespiratory function, and if they engage in running and other high-volume activities, they may experience temporary dyspnea, which can be recovered after rest. Running dyspnea may be due to a variety of reasons, if the symptom fails to improve or even gradually aggravate, you need to consult a regular hospital in a timely manner, and cooperate with the doctor to improve the examination and standardize the treatment.