The first way to make the midline of abdominal muscles more obvious is to brush body fat. If the body fat is low enough, practice abdominal muscle tearing in the second way. Let's talk about the middle seam of the chest muscle first. Chest muscles emphasize thickness. If the subjects' chest muscles are big enough and full enough, they can practice flying birds more, and the effect is very good. If the subject's chest muscles are not plump enough, personally, it is not recommended to practice more birds. It's more important to practice thick chest muscles first.