A randomised, double-blind, cross-over study to evaluate the effect of 6 weeks treatment of orally inhaled tiotropium + olodaterol fixed dose combination (5/5 µg) compared with tiotropium (5 µg), both delivered by the Respimat® Inhaler, on breathlessness during the three minute Constant Speed Shuttle Test (3min CSST) in patients with Chronic Obstructive Pulmonary Disease (COPD).

- All patients must sign an informed consent consistent with International Conference on Harmonization - Good Clinical Practice (ICH-GCP) guidelines prior to participation in the trial, which includes medication washout and restrictions.;- All patients must have a diagnosis of chronic obstructive pulmonary disease and must meet the following spirometric criteria:;Patients must have relatively stable airway obstruction with a post-bronchodilator 30% <<= FEV1 <80% of predicted normal (ECSC); GOLD 2 - 3, and a postbronchodilator FEV1/FVC <0.70 at visit 1.;- Male or female patients, between 40 and 75 years of age (inclusive) on day of signing informed consent.;- Patients must be current or ex-smokers with a smoking history of more than 10 pack-years. Patients who have never smoked cigarettes must be excluded.;- Patients with a score on the Baseline Dyspnea Index (BDI) < 8 at visit 0.;- Patients with hyperinflation at rest, defined as FRC > 120% predicted at visit 1.;- BORG dyspnea score ><=4 at the end of 3min CSST at visit 2;- Patients must be able to perform technically acceptable pulmonary function tests (spirometry and body plethysmography), must be able to complete multiple shuttle walk tests during the study period as required in the protocol.;- Patients must be able to inhale medication in a competent manner from the Respimat® inhaler and from a metered dose inhaler (MDI).

- Patients with a significant disease other than COPD; a significant disease is defined as a disease which, in the opinion of the investigator, may (i) put the patient at risk because of participation in the study, (ii) influence the results of the study, or (iii) cause concern regarding the patient's ability to participate in the study;- Patients with a, in the opinion of the investigator, clinically relevant abnormal baseline haematology, blood chemistry, or creatinine >x2 ULN will be excluded regardless of clinical condition.;- Patients with a current documented diagnosis of asthma. For patients with allergic rhinitis or atopy, source documentation is required to verify that the patient does not have asthma.;- Patients with a COPD exacerbation in the 6 weeks prior to screening (visit 1).;- A diagnosis of thyrotoxicosis (due to the known class side effect profile of B2-agonists);- A history of myocardial infarction within 6 months of screening visit (visit 1);- Life-threatening cardiac arrhythmia as judged by the Investigator.;- Known active tuberculosis;- Any malignancy unless free of disease for at least 5 years (patients with treated basal cell carcinoma or squamous cell skin cancers are allowed);- A history of cystic fibrosis;- Clinically relevant bronchiectasis, as judged by the Investigator.;- Patients with severe emphysema requiring endobronchial interventions within 6 months prior to screening.;- A history of significant alcohol or drug abuse, as judged by the investigator.;- Any contraindications for exercise testing as outlined below.;- Patients who have undergone thoracotomy with pulmonary resection (patients with a history of thoracotomy for other reasons should be evaluated as per exclusion criterion No. 1).;- Patients being treated with any oral or patch ß-adrenergics;- Patients being treated with oral corticosteroid medication at unstable doses (i.e., less than four weeks on a stable dose) or at doses in excess of the equivalent of 10 mg of prednisone per day or 20 mg every other day;- Patients being treated with antibiotics for any reason (not limited to exacerbation infection) within 4 weeks of screening visit.;- Patients being treated with PDE4 inhibitors within 3 months of screening visit (e.g.roflumilast) should not be enrolled and PDE4 inhibitors should not be withdrawn for the purpose of enrolling in this study.;- Patients who regularly use daytime oxygen therapy for more than one hour per day and in the investigator's opinion will be unable to abstain from the use of oxygen therapy during clinic visits;- Patients who have completed a pulmonary rehabilitation program in the six weeks prior to the screening visit (visit 1) or patients who are currently in a pulmonary rehabilitation program.;- Patients who have a limitation of exercise performance as a result of factors other than fatigue or exertional dyspnea, such as arthritis in the leg, angina pectoris or claudication or morbid obesity.;- Patients with an endurance time >=12 minutes during the incremental shuttle walk test (visit1).;- Patients with oxygen saturation < 85% (on room air) at rest or during exercise.;- Patients who have taken an investigational drug within one month or six half-lives (whichever is greater) or in case the investigational drug (sub) class is listed within the washout period specified prior to screening visit (visit 1);- Patients with known hypersensitivity to ß-adrenergics and/or anticholinergic drugs, BAC, EDTA or any other component of the Respimat® inhalation solution;- Women who are pregnant, nursing, or who plan to become pregnant while in the trial;- Women of childbearing potential not using a highly effective method of birth control.;- Patients who have previously been randomized in this study or are currently participating in another study;- Patients who are unable to comply with pulmonary medication restrictions prior to randomization (see protocol section 3.3.3.)