It is an exaggeration to say that the PE teacher loses 20 Jin a day. Generally speaking, you can't lose 20 pounds in the gym for ten days. Besides, other people will gain weight in 1-2 weeks when they just start fitness, because exercise muscle congestion will lead to weight gain, and then slowly decline, and it will not drop much in a day, at most it will be about half a catty to a catty.
So, this is a physiological change. Even if you take a private class of professional customized weight loss training, it will take about three months to see some effects. After half a year, you can see some changes in slimming. After a year, you can basically lose weight successfully. But it should be noted that even after losing weight successfully, you should pay attention to your diet. If you don't pay attention to all aspects of your diet, you will gain weight again.
It is also a good way to lose weight by private education, and you can customize the way to lose weight according to your own characteristics. But it takes a process, and it takes a certain time to keep exercising every day to achieve the effect of slimming.