This theory comes from "it is difficult to get the most muscle without increasing fat". As far as muscles are concerned, we all know that adequate sugar intake and high blood sugar are the main indicators of protein synthesis, and the concentration of muscle glycogen also determines your exercise intensity. Therefore, while eating a lot of high GI carbohydrates to gain muscle, it will inevitably bring side effects of fat increase. But this doesn't mean that the opposite is true, just like a plant blooms and smells, but it doesn't mean that you smell a plant and it will bloom. Does eating fat alone affect muscles? Yes! But it is mainly concentrated in the lower limbs, because after all, the weight has increased and the lower limbs bear more weight. But it has little effect on upper limbs. There are only two reasons for being thin: eating less and sleeping late. Don't say that no matter how you eat, you are not fat. You really just eat less. Okay, I see why. If you want to gain weight, you must eat hard. Are you sure you can eat without exercise? If you could eat, you would have already eaten. Why are you always so thin? Well, suppose you really have super willpower, you can eat five meals a day, and you can really gain weight. But why do you need it? You can increase your appetite through exercise, and then take enough protein and carbohydrates to gain muscle in one step. Why do you have to take two steps? According to my experience, people who have the idea of "practicing after I get fat" are really just lazy. If you want to change, don't wait for you to gain weight. Better start now. I don't know if it is suitable for both men and women, or if there are any requirements for physical fitness, but my fitness coach (the coach who participates in bodybuilding competitions, not soliciting customers in the gym) was recommended by a teacher to gain weight first and then lose weight. His body shape is much better, but he is a girl. I don't think it is easy. After all, he is a professional. In addition, girls will cry if they are fat and can't lose weight. If you don't die, you won't die. As everyone says, consider finding a boyfriend. In fact, it is not difficult to get in good shape as long as you find a good coach. I always take more than 20 private lessons, and because I stopped for two months in the summer vacation, my shoulders opened 1.5, and my shrugging problem disappeared.