Health-keeping verbs can also be nouns. It originally refers to a medical activity of Taoism to maintain life, strengthen physique and prevent diseases through various methods, so as to achieve longevity. Raise, that is, the meaning of nursed back to health, maintenance and tonic; Life means living, surviving and growing. In the modern sense, "health preservation" refers to actively carrying out material and spiritual activities according to the law of human life process.