Super simple ~ use breathing to exercise abdominal muscles

Thoracoabdominal breathing method, simply put, is to straighten your back and while contracting your lower abdomen, slowly inhale through your nose and feel your chest Expand, hold it for about 1 to 3 seconds, and then slowly exhale through your mouth.

This action can be practiced whether you are standing on the bus or sitting on a chair, and it is quite effective.

If you stick to it for 3 months, your abdominal muscles will appear before you know it.