Swimming can improve immunity and prevent colds. When swimming, because it is cold water, it can improve the body's adaptability to the environment, thus improving the body's immunity and reducing the chance of catching a cold, thus reducing the chance of asthma.

Enhance cardiopulmonary function. When swimming, the burden on the respiratory muscles is greatly increased. The water pressure of 12- 15kg compresses the whole brain cavity and contributes to vital capacity. The data shows that swimming for half an hour every day in a summer can increase vital capacity by 500 ml.

Swimming can effectively exercise the pectoral muscle, diaphragm muscle and intercostal muscle, and improve the ventilation function of the lungs. Reasonable exercise is beneficial to the treatment and rehabilitation of asthma patients.