Sample Size and Power Calculation: A sample size of 16 per group provides 80% power to detect a 1 Borg unit difference between groups in dyspnea intensity at a standardized work rate during incremental cycle exercise, based on a standard deviation of 1 unit, α=0.05 and a 2-tailed test of significance. This sample size is also adequate to detect statistically significant differences in our other outcomes (operating lung volumes) based on previous studies in humans.