Zhengqi is a term used in traditional Chinese medicine, which mainly refers to the ability of the human body to resist evil, and has the functions of resisting evil and preventing diseases, maintaining the internal balance of the body, etc. Zhengqi is the basis of the body’s ability to resist diseases. 1. Resisting evil and preventing disease: Zhengqi is the foundation of the body’s ability to resist disease, and the strength of Zhengqi is directly related to the occurrence of disease, as well as closely related to the ability of the body’s self-repairing ability to repel evils out of the body after the occurrence of a disease and after the disease. The positive energy is abundant, the body is strong in disease resistance, the disease-causing evil is difficult to invade, the disease can not happen. 2. Maintain the internal balance of the body: In addition, the positive qi also has the role of maintaining the internal balance of the body, mainly to enable the body to adapt to changes in the internal and external environment, to maintain a coordinated balance of yin and yang in the body. Traditional Chinese medicine believes that “positive qi within the body, the evil can not be dry”, refers to the positive qi for the body to resist the important role of disease prevention.