Objective: The investigators studied the effects of respiratory muscle stretching in an 8-week pulmonary rehabilitation program. Methods: This was a simple-blind parallel controlled trial, conducted an out-patient clinic. Twenty six patients with COPD (mean age 68 ± 6 y, percent of predicted FEV1 47 ± 16) were randomized to either respiratory muscle stretching group plus exercise training (RMS), and exercise training group (Sham), in an 8-week exercise program that had 3 sessions per week. The investigators measured inspiratory and expiratory muscle strength (by maximal inspiratory and expiratory pressure - PIM and PEM), exercise capacity (by 6-minute walk distance), dyspnea and quality of life.

Inclusion Criteria:

• Subjects between 40 and 75 years of age referred by a physician to the Pulmonary Rehabilitation Program
• With a clinical and spirometric diagnosis of moderate to severe COPD according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD), in a stable condition (without exacerbations or infections for at least a month)
• Former smokers

Exclusion Criteria:

• Patients with a known history of asthma, or severe and/or unstable heart disease
• Any other pathological condition that could impair their physical activities