Christian,
Well, exercising can diffanatly help, um, I havent been exercising although every now and then I will. Do you take hypertonic saline? The reason I credit this so much is because Ive noticed a great big difference, ever since Ive been on it, my pfts have been rising so you can see why I am so pleased with it, I do know that not everyone has a great experience with it tho. I use 7% hypertonic saline and some use 3%. I cant think of anything else that could help bring your pfts up more except for exercising and hypertonic, doing your meds all the time can help too.