Inclusion Criteria:  Patients after COVID-19 Patients expressing subjective feelings of limited tolerance to exercise and above 50% greater fatigue compared to their pre-COVID-19 levels (symptoms must have continued for at least four weeks since the last symptoms of infection)  Exclusion Criteria:  Patients with cardiological complications Patients with pulmonological complications Patients with Chronic Obstructive Pulmonary Disease and/or asthma