1, running immediately after fitness helps to stretch and relax muscles. If you can't relax after general fitness, you will reduce the flexibility of your muscles, that is, your strength will increase and your flexibility will decrease. Therefore, we should pay attention to relaxation after fitness, such as combining fast running immediately after frog leaping and squatting.

2, running time before fitness should not be too long, too tired, should give priority to with warm-up, body sweating slightly is the best. Otherwise, it will consume energy and affect the fitness effect.

3. It doesn't have any effect on fitness to keep fit for two or three hours before running. The interval is too long, which basically just increases the amount of exercise.