I was taught in Respiratory Rehab, to exhale with your lips pursed as though you are gonna whistle, and exhale slowly. That restriction of exhaling helps get out the Co2 (carbon dioxide) from your lungs, so that there will be more room for the oxygen when you breathe in. This seemed uncomfortable to me for a little while, but then I noticed that I was gettin back to relaxed, semi-normal breathing much faster. So I try to practice that whenever my breathing starts gettin labored. The problem with Emphysema is that, you cant get the Co2 out to make room for the Oxygen, so this truly does help. Hope this helps you.