I just stumbled across a breathing method called Buteyko breathing. Basically what his logic is that we overbreath causing us to lose too much co2 so you dont transfer oxygen. This method is geared toward asthmatics but i have a feeling this may help people in the cf community. You can go on youtube.com and type in Buteyko breathing exercises and learn how to do it and start implementing it today. I hope this helps others!
-Nick
-Nick