[Improvement of physical activity in patients with COPD]

Physical activity (PA) is defined as any bodily movement produced by skeletal muscles that results in energy expenditure beyond resting energy expenditure. Physical activity is an important clinical parameter closely related to morbidity and mortality in COPD. A self-report questionnaire is often subject to recall bias, correlates only poorly with objectively qualified PA, and does not provide an accurate estimate of free-living energy expenditure. In contrast, tri-axial accelerometers generate objective data in terms of quantifying steps or body movements performed over a period of a time. Low-intensity and home-based pulmonary rehabilitation with the feedback from using pedometer was effective in improving PA, and the improvements of physiological factors were correlated with increased walking time in stable elderly patients with COPD.