High Flow Nasal Cannula and Exercise Testing in Chronic Obstructive Pulmonary Disease (COPD)

In this study the investigators will determine whether the use of High Flow Nasal Cannula Oxygen during test enhances exercise performance in COPD patients on a treadmill.

Design: interventional, crossover, randomized. The main goal of this study is to compare the maximum speed reached in an Incremental Load Treadmill Test (ILTT) and max time tolerated in a Constant Treadmill Load Test (CTLT) while using High Flow Nasal Cannula Oxygen (HFNCO). Patients will be evaluated through two different kinds of tests: Incremental Load Treadmill Test (ILTT) and Constant Treadmill Load Test (CTLT). Each test will be conducted two times, once using High Flow Nasal Cannula Oxygen and the other breathing room air. In total, each patient will be evaluated four times on four different visits. The testing order will be randomized through STATA. The following variables will be measured before, during and after each test: Max speed reached in an Incremental load test: Km/h Max time tolerate in a Constant Load Test: in seconds Oxygen saturation: % Dyspnea: Modified Borg scale (0-10) Cardiac rate: beats per minute Respiratory rate: breaths per minute Blood pressure: mmHg Lower limbs fatigue: modified Borg scale (0-10) Global comfort according to the device used: visual analogue scale (VAS) 0-10