Low altitude baseline measurements will be performed in Zurich (469m asl) including Echocardiography, right heart catheterization, six Minute Walking test (6MWT), pulmonary function test, clinical assessment and blood gas analysis at rest and under exercise. Randomly assigned to the order of testing, the participants will e tested under simulated altitude (FiO2: 15.1% with the "AMC Altitrainer") and shamed altitude with the same device. During the exposure to simulated altitude (FiO2: 15.1%) and shamed altitude of 1 hour each, the participants' ECG and non-invasively assessed blood pressure by Finapres at rest and under exercise will be collected.
