This clinical study is part of a randomized controlled trial including 11 hospitalized patients with exacerbation COPD from March 2012 to October 2014. Exacerbation was considered according to the GOLD (Global Initiative for Chronic Obstructive Lung Disease)  criteria. COPD was confirmed prior to hospitalization by spirometry using a bronchodilator where forced expiratory volume in one second/forced vital capacity was less than 0.70 (FEV1/FVC < 0.70) and severe exacerbation was considered when hospitalization was needed and changes in maintenance medication or the introduction of corticosteroids and/or antibiotics was needed. The exclusion criteria were a Glasgow score < 15, Borg dyspnea score > 7 , instable heart disease, limited mobility, hemodynamic instability, and mechanical ventilation.