In fact, you can see a person's fat and thin from this action, because it is a very figure-showing action. If you have fat on you, it won't look good after you put it out, because the meat will show up wherever you put it. Therefore, if you want to challenge the comic waist, you must first have a perfect body. Not only can you not have fat on your body, but your body proportion should be appropriate and perfect.
Soft body In addition to challenging this action, the body must be very soft, otherwise it can't be folded 90 degrees at all. As can be seen from the picture, to challenge this action, you have to fold your body into two 90 degrees, which is very difficult. If you are not a soft person, you cannot challenge it.
Of course, this action is also dangerous. If there is no professional guidance, it may damage your health. So don't try it easily while you are curious, because there may be some dangerous consequences. If you want to try, you'd better find some professionals to guide you and pay attention to prevent accidents.