Introduction
Chronic obstructive pulmonary disease (COPD) is characterized by exertional dyspnea
and reduced exercise tolerance.1–3 One of the major factors in exercise tolerance
limitation in COPD is dynamic hyperinflation during exercise, which results in a
disparity between inspiratory effort and ventilatory output, and is likely to be important
in individuals with moderate-to-severe COPD.2,4 Lung hyperinflation causes a
decrease in inspiratory capacity (IC) and an increase in end-expiratory lung volume