when ever i breath in by the middle of my chest bulges as my chest expands. i havent seen this with anyone else. i havent felt any pain or anything yet , and i have this from my childhood. but what i noticed is can walk as fast as i can for long time with no breathing problems but i cant run like that because i feel stress in breathing through nose . Is there any problem with that ?
A bulge in your chest could be a congenital malformation which is not affecting your lung function. While running, one breathes through mouth and not nose, so don't be worried. But if you feel, you are very breathless while running, you should get yourself checked for exercise induced asthma.