In this randomized, double-blinded, sham-controlled clinical trial, the investigators will test the effectiveness of the use of a positive expiratory device (PEP Buddy) vs. sham in participants with COPD in Pulmonary Rehabilitation and after discharge from Pulmonary Rehabilitation for up to one year. The investigators will compare changes in quality of life metrics and measurements of functional capacity between the intervention and sham groups over the course of the study.
