Pulmonary function tests and rehabilitation in 2012: beyond sitting position

The benefits of pulmonary rehabilitation (PR) programs in patients with chronic obstructive pulmonary disease (COPD) are well established today [1]. PR programs improve exercise tolerance and health related quality of life; nevertheless, the role of inspiratory muscle training in rehabilitation programs remains controversial [2]. This is particularly due to the absence of clear data on the effects of inspiratory muscle training on outcomes in patients with COPD such as exercise capacity, functional exercise capacity, and dyspnea during activities of daily living. In the present issue of Multidisciplinary Respiratory Medicine Ki-song Kim & coll [3] present data about the effects of breathing maneuver and posture on muscle activity of inspiratory accessory muscles in COPD patients, concluding that the different involvement of accessory respiratory muscles can be easily studied in these patients, making it possible to monitor respiratory load during pulmonary rehabilitation. Though data on the correlation between dyspnea and breathing pattern were lacking, the study considered particular real life situations as pursed lip breathing and bracing arms position. It is well known that posture during spontaneous quiet breathing influences not only thoraco-abdominal kinematics but also gas exchange and the cardiovascular system. Hence, in recent years functional studies and respiratory rehabilitation procedures have taken posture into account as a strategic way to understand and treat cardiorespiratory disability. PR in the past was performed with good results for patients but often subjects were studied in seated position only, with spirometry measuring forced expiratory volume in 1 s. In this way the evidence of cardiorespiratory function improvements after treatment was lacking. Moreover PR was considered like a flying bumble-bee [4] (according to conventional aerodynamic principles,