Some people lose a lot of weight after swimming, probably because of insufficient exercise. At first, swimming was in the 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 use fat at all. In the next hour, in the state of moderate intensity exercise, the aerobic metabolism of sugar provides energy supply. If you want to lose weight, you should swim for more than 40 minutes at a time before you start to burn fat. Experts believe that swimming 3-4 times a week, each swimming time 1 hour, is most beneficial to lose weight.

Swimming is one of the sports that men, women and children like. Ancient swimming, according to the existing historical data, is a consistent view at home and abroad, which originated from people living in rivers, lakes and seas in ancient times. In order to survive, they must catch waterfowl and fish as food in the water, and gradually learn to swim by observing and imitating the swimming movements of fish, frogs and other animals.

References:

Swimming-Baidu Encyclopedia