What is the standard of a person's health? According to western medicine, Chinese medicine is vitality, which is qi and blood. Good qi and blood means good health. A person who insists on exercising for a long time will often hurt his vitality and have low efficiency in spermatogenesis. So a person with qi deficiency should avoid strenuous exercise, or the disease will find him. Only through Taoist practice can qi and blood be reversed and diseases be avoided.