Exercise training and chronic obstructive pulmonary disease: past and future research directions.

Chronic obstructive pulmonary disease (COPD) is a major cause of death and disability in the United States. It is characterized by symptoms of breathlessness that result in sedentary lifestyle, physical deconditioning, and reduced quality of life. Previous research has shown that exercise training in patients with COPD will improve physical function and may help improve the quality of life. Unfortunately, the majority of these previous studies have not been pursued with adequate scientific rigor and the conclusions regarding the efficacy of exercise as an adjunct in the treatment of COPD are equivocal. The purpose of this article is to review the previous research that has focused on the effects of exercise training on individuals with COPD, to examine the problems with this previous research, and to emphasize the need and identify topics for further outcome-based research.