Young students are in a critical period of growth and development, and their bodies are relatively plastic. Practice has proved that physical exercise plays an important role in cultivating students' correct body posture and promoting their growth and development. Regular participation in sports activities can promote the blood circulation of bone tissue, make bone density thicker and bones thicker, and significantly improve the firmness, bending resistance, fracture resistance and compression resistance of bones. In addition, regular physical exercise can also make bones grow out, which is of positive significance to the height growth of young students.

2. Improve the functional level

Physical exercise can also effectively improve the functional level of the body. Participate in sports activities, increase energy consumption, metabolites and vigorous metabolism in the human body, thus improving the functional level of various organ systems such as nervous system, blood circulation system, respiratory system and digestive system.

3. Develop physical fitness and basic activity ability.

Physical exercise also plays an important role in developing basic activities such as walking, running, jumping, throwing, climbing and so on, such as speed, strength, endurance, agility, coordination, balance and flexibility. 4. Enhance the adaptability to the external environment

The external environment, including the natural environment and social environment for human existence, is a very complex system. Changes in the natural environment will inevitably affect people's lives and health. The human body must adjust the functions of various organ systems at any time to adapt to the changes in this environment and keep the internal and external environment of the human body relatively balanced. Regular physical exercise can improve students' adaptability to the natural environment and enhance their resistance to diseases.

It is worth noting that the development of modern science and technology and the improvement of people's material living standards will objectively have a negative impact on the development of people and society. Such as the biological degradation of human beings, the emergence of modern civilization diseases, the increase of social pressure, the strengthening of interpersonal relations, the weakening of interpersonal relations and so on. , giving new meaning and connotation to the function of school physical fitness. The fitness function of school physical education will be expanded from one-dimensional structure to three-dimensional structure, which will promote people's physiological and psychological development and social adaptability. This is not only the need of human development, but also the new mission entrusted to school physical education by the times.