cardio, cardio, cardio! it helps lung function so much. in jr. high and high school, i ran cross country and track and though I've always been fortunate to have lung function high enough to be able to compete, I think it's running that kept me there. at the beginning of the seasons, i'd always have to "clear out" a little - but by the end of the seasons i was breathing better than an average person. running served as treatments, too - maybe even works better. it's amazing if you can do it.