Therefore, you must understand how abdominal breathing becomes chest breathing. You need to know their characteristics and specific differences first. Both abdominal breathing and chest breathing use lungs, so you have to expand your chest. Theoretically, most of it should be done by sinking the diaphragm and expanding the lower end of your chest, but if the abdominal wall muscles relax, it is impossible. This is done by lifting the chest through the shoulder and neck muscles. This posture changes from abdominal posture to chest posture.
If your abdominal muscles relax, you can't make up for it by breathing through your chest. Well, you can't breathe, you will suffocate. However, the use of shoulder and neck muscles in chest high pressure breathing leads to shoulder tension, poor shoulder stability, glenohumeral muscle strain, head and neck movements and shoulder movements, which are the reasons for (but not all) excessive breathing.
You see, this is all a cycle. The general mainstream view is that abdominal breathing is better than chest breathing. The reason is that they smoke deeper. There are many views that chest breathing has many advantages over abdominal breathing, especially in the technical part of coloratura soprano, because the singing depth of this part does not require much breathing, and the flexibility of breathing has sufficient requirements for the breathing frequency of vocal cords. In fact, it depends on how you define chest breathing and abdominal breathing.