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 two different oxygen delivery devices (High Flow Nasal Cannula Oxygen and The Mask Venturi).
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 HFNCO and the other time with The VM.
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:
1. Max speed reached in an Incremental load test: Km/h
2. Max time tolerate in a Constant Load Test: in seconds
3. Oxygen saturation: %
4. Dyspnea: Modified Borg scale (0-10)
5. Cardiac rate: beats per minute
6. Respiratory rate: breaths per minute
7. Blood pressure: mmHg
8. Lower limbs fatigue: modified Borg scale (0-10)
9. Global comfort according to the device used: visual analogue scale (VAS) 0-10
