Exercise is HUGE for CF longevity. Muscle training is also great, especially for male CF's.
I walk atleast 5-7 miles per day mon-fri at work, usually briskly, and some bike thrown in. Mon, Wed, and Fri I do heavy weight at L.A. Fitness near my work. On bench I do 6 sets of 5 reps @ 276lbs. Then I move to flies and do 3 sets of 10 @ 190-210. Then I move to preacher curls and do 3 sets of 10 @ 110. By the time i'm done with that usual routine it's close to haul booty to work time, so I usually don't have time for other machines but if I do I like the roman chair and pull down.
I haven't tried to max my bench in a very long time, but i'd like to see what max I could get up in the air now. I suppose if I absolutely had to (gun to head type thing) I could maybe do 300 or slightly over that. Weight training is awesome, and I feel and look amazing. I'm much stronger than some of the meat heads at my gym, and as a cystic i'm proud of that accomplishment.