Exercise training is the most common form of non-pharmacologic therapy prescribed to chronic obstructive pulmonary disease (COPD) patients. In the pathogenesis of COPD, only ventilation limitation is not a problem, and many patients have also caused muscle dysfunction. Therefore, the treatment for the muscle dysfunction is required. Pulmonary rehabilitation has been shown to be as highly effective as pharmacotherapy for improving lung function as evidenced by contributing to improvements in shortness of breath, quality of life, exercise capacity, depression, and rates of hospitalization. In addition, it has also been recommended that the patients who fail to clinically improve solely with pharmacotherapy undergo pulmonary rehabilitation.