Breathing exercise methods are used to increase ventilation, improve respiratory function, and increase activity endurance through lip-contraction breathing, abdominal breathing, and other methods. 1. Lip-contraction breathing: Close your mouth, inhale deeply through your nose, and then exhale slowly with your lips in a whistling motion to minimize the collapse of the airway after exhalation. 2. Abdominal Breathing: When inhaling, puff up your stomach and retract it when exhaling to improve breathing by exercising the diaphragm function. 3. Deep inhalation and coughing: After doing deep inhalation, hold your breath slightly and then do explosive breathing to effectively cough phlegm out of the lungs. A variety of breathing exercises can be combined, can be carried out under the guidance of the doctor’s breathing training exercises, to achieve better exercise respiratory function.