This study will examine the causes of breathing difficulty in people living with chronic obstructive pulmonary disorder (COPD) and explore any differences in men versus women. This information will be compared with healthy individuals, as well as smokers at-risk of having COPD to see how breathing difficulty, exercise performance, and the size and shape of the different parts of the lungs impacts differences between these population groups.

The study involves a total of 4 visits (3 in-person, 1 by phone). All in-person visits will be completed at St. Paul's Hospital, Vancouver BC. Visit 1 will involve questionnaires, lung function tests, and a medical examination by our study physician. Visit 2 will involve lung function tests and cycling on a stationary bicycle. Visit 3 will involve a non-contrast computerized tomography (CT) and magnetic resonance imaging (MRI) scan. These tests involve you remaining still, while performing a series of breathing maneuvers to obtain detailed images of your lungs. Upon completion of the study, participants will discuss the results of the study with our study physician by phone call.