Many foreign scholars have revealed that the state of human ability changes overnight. Every day from 8: 00 to 12, from 14 to 17, muscle speed, strength and endurance are in the best condition. If you do physical exercise and sports training during this time, the effect will be better. But from 3: 00 to 5: 00, 12 to 14, it is in a relatively low state. If you are engaged in sports during this time, you are easy to get tired, and when the "load" is too large, the probability of sports injury is high.

This shows that people should choose the best time to engage in sports activities according to the possibility of objective conditions in order to receive good fitness and training results.