Sun Simiao, a health care expert in the Tang Dynasty, said: "The way of health care often lies in hard work." Spring is the best time for exercise. In the cold winter, people have more indoor activities, so the functions of various organs and organs have declined to varying degrees. As the climate gets warmer in spring, we should strengthen outdoor sports, stretch our limbs and exercise our bones and muscles. After a winter confinement, the yang in the human body should also move with the trend of spring, and rise outward when spring blooms and spring grows, corresponding to the qi of heaven and earth.

Beautiful spring, fresh air and full of vitality are pleasing to the eye. This kind of environment and climate is also conducive to the human body to vomit the old and absorb the new, transform the essence and blood with the true qi, and nourish the viscera. Modern medical research has also proved that in this disease-prone season of spring, insisting on physical exercise can enhance human immunity and prevent people from getting sick. Therefore, in the six solar terms in spring, it is best to take some time out for physical exercise every day. Let the body bathe in spring, absorb the vitality of nature to the maximum extent, and charge the vitality.

The so-called fitness exercise refers to some sports in outdoor, courtyard, park and nature, such as flower viewing, walking, practicing Qigong, playing Tai Ji Chuan and flying kites. Outdoor, the air is rich in negative ions, which is one of the important substances for maintaining health of life on earth. The negative ions in the air can promote the normal physiological activities of human body, regulate the excitement and inhibition of central nervous system, improve the function of cerebral cortex, promote hematopoietic function and ventilation ability of lung, and increase the absorption of oxygen and the discharge of carbon dioxide, thus making people energetic and clear-headed, and at the same time having certain effects on people's life, mood, memory, growth and development, muscle strength, etc. There are only about 30 negative ions per cubic centimeter of air in big cities, but there are more than 100 negative ions per cubic centimeter in street greening areas, which can be increased to 400-600 in parks, 700- 1000 in suburban wilderness and as high as 20,000 in coastal areas, forests, valleys and waterfalls.

Besides, outdoor activities spend much longer in the sun than usual. Ultraviolet rays are natural fungicides in sunlight, which can increase the number of white blood cells in the blood and weaken the pathogenicity of bacteria and viruses. At the same time, it can also convert dehydrocholesterol in human skin into vitamin D, promote the metabolism of calcium and phosphorus in the body, be beneficial to the growth and development of bones, and be very beneficial to the prevention of rickets in children and osteoporosis in middle-aged and elderly people.