Swimming has a good fitness and shaping effect, and it will be very full of exercise for the waist and abdomen, especially easy to develop a small waist. "In the beginning, swimming was in an anaerobic exercise stage. Energy consumption mainly depends on anaerobic glycolysis of sugar. At this stage, the exercise is very intense, people are short of breath and lack of oxygen, and they don't need fat at all. Continue to exercise, and the human body begins to enter the stage of aerobic exercise. After 1 hour, in the state of moderate intensity exercise, the energy is supplied by aerobic metabolism of sugar. If you want to lose weight, you should swim for more than 40 minutes at a time before you start to burn fat. Keep training for two hours every day, and it's best to get in touch with butterfly stroke, and your waist will come out in one month.