Inclusion Criteria:  Age between 50 and 80 Individuals infected by the SARS-COV2 virus, with positive PCR diagnosis Still having breathlessness and fatigue at least 3 months after the diagnosis of COVID-19 or patients presenting an increase of 1 point (compared to before infection) on the Modified Medical Research Council scale. Able to perform a maximal cardiopulmonary stress test and exercise training program in accordance with current guidelines on cardiopulmonary rehabilitation. Able to read, understand and sign the information and consent form.  Exclusion Criteria:  pulmonary embolism diagnosed by scintigraphy Absolute and relative contraindication to exercise stress test and / or exercise training Recent cardiovascular events (cardiac decompensation or angioplasty or cardiac surgery, less than 1 month; valvular disease requiring surgical correction, active myopericarditis, severe ventricular arrhythmias not stabilized under treatment). Kidney failure requiring dialysis heart failure (NYHA III or IV)