After walking or light activity, you can feel shortness of breath, palpitations (fast heartbeat), hypoxia (dyspnea) and other symptoms, the common cause may be cardiac diseases such as: heart failure, ischemic cardiomyopathy; may also be pulmonary diseases such as: chronic bronchitis with emphysema, pulmonary fibrosis, lung infections, pulmonary heart disease and so on. Normal people’s basic activities by inhalation of oxygen to the lungs for the exchange of oxygen and carbon dioxide in the blood vessels, the exchange of carbon dioxide discharged from the body and carry oxygen blood pumped through the heart to supply the body’s various organs so as to provide oxygen for the various tissues, but when the heart or lungs out of the normal physiological process of the above mentioned decline will be weakened or destroyed, resulting in shortness of breath, palpitations, hypoxia after the activity. When the above situation occurs, it is recommended to stop and rest immediately, and observe whether it can be relieved on its own, and when the symptoms are serious, it is recommended to go to the hospital for further consultation to clarify the cause of the disease.