BACKGROUND: Although it is generally accepted that aerobic exercise training does not change lung structure or function, some work suggests that greater pulmonary vascular structure and function are associated with higher exercise capacity (peak rate of oxygen consumption [V˙o RESEARCH QUESTION: Is there a cross-sectional association between the pulmonary vasculature and V˙o STUDY DESIGN AND METHODS: Participants from the Canadian Cohort Obstructive Lung Disease (CanCOLD) study were categorized as follows: participants with normal spirometry who had never smoked (n = 263), participants with normal spirometry who had ever smoked (n = 407), and COPD: individuals with spirometric airflow obstruction (n = 334). Total vessel volume (TVV), volume for vessels <
5 mm RESULTS: General linear regression models revealed that even after controlling for FEV INTERPRETATION: Our results suggest that pulmonary vascular structure and Dlco are independently associated with V˙o