When exercising more than three times a week, the increase of maximum oxygen uptake gradually tends to be flat; When the number of exercises increases to more than 5 times, the maximum oxygen uptake increases slightly; However, when you exercise less than twice a week, it often doesn't change. It can be seen that 3-4 times a week is the most suitable frequency. However, due to the exercise effect and accumulation, the interval should not exceed 3 days. As a general health care, it is certainly better to exercise once a day.