Inclusion Criteria:  patients 14 years or more diagnosis of DB after SARS-CoV-2 at our long covid clinic using a combined approach of symptoms and CPET analysis in the hospitals of Sion, Martigny or Rennaz Inclusion between November 2020 and until the end of October 2021  Exclusion Criteria:  Refusal to participate comorbidities preventing the CPET or PFT to be carried out