The main reason is that after you stop training, your consumption is reduced, but your stomach's reflex ability is not so fast, and you are still making up according to the amount during training. Therefore, the key to keeping fit after stopping training is to reduce intake. Of course, I suggest you don't stop exercising. It is not easy to stick to it. It is also very painful to want to practice again after stopping training, and you have to bear great psychological and physical pressure.