Deep breathing exercises can be incredibly beneficial to people with the pectus excavatum condition since it will help to expand the ribcage and push out your sternum.
1. Stand straight with a good posture.
2. Keep hands by your side and inhale, take a big breath, as big as you can possibly do and push out your chest.
3. Hold your breath for 5-30 seconds and place your hands behind your head. The aim is to expand the chest as much as possible.
This breathing technique in just as effective lying down on the ground or sitting straight in a chair just remember to breath in DEEP and if you do this consistently you should notice some improvement in about 3 months