1 It is related to people's physique: people's physique is strong or weak, and the load after exercise has different effects on everyone. 2 It is related to the intensity of exercise: don't exercise too much when you are just exercising, and your body can't adapt. It is related to the habit after exercise: it is also important to choose the exercise time. It is suggested to start mental work half an hour after supper. Don't sleep for less than 2 hours after exercise.