I don't know if its been posted anywhere else but you can do chest expansion exercises.
Just grab a towel that you roll up and place around your chest and hold tightly at the front so it restricts you. You then concentrate on expanding your chest with some (maybe 10 or 20 or whatever) deep breaths. Hold them for 5 seconds or so before letting out air. Don't do them, too fast or you might hyperventilate
This will let you concentrate on your breathing. I got to the point when I couldn't even blow up a balloon due to reduced expansion but now am about half of what is considered normal and I also have to keep on reminding myself not to breathe thru my stomach.
Don't think you can - KNOW YOU CAN
