Wonderful little butterfly, the decompression password of compressed package. Kneel down!

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When students do strenuous exercise, such as running 100 meters, the oxygen they breathe at the beginning of the race has not reached the cells to participate in the "burning" activity. In other words, the exercise is over before the oxygen works. In the process of using oxygen, there is a considerable time difference, which determines the intensity and brevity of exercise and becomes anaerobic exercise. For example, 100 meter dash, 200 meter dash, 100 meter dash.