Exercise capacity and physical activity in patients with COPD and healthy subjects classified as Medical Research Council dyspnea scale grade 2.

Patients with chronic obstructive pulmonary disease (COPD) are often classified by Medical Research Council (MRC) dyspnea grade and comparisons thus made to healthy individuals. The MRC grade of a healthy population is assumed to be grade 1, although this may be inaccurate. Physical activity and exercise capacity are not well-defined for those with MRC grade 2. This study was undertaken to establish whether there are differences in physical activity and exercise capacity between individuals with COPD and healthy controls, who have all assessed themselves as MRC grade 2.