RT Journal Article SR Electronic T1 Tolerability and safety of high-intensity continuous and intermittent exercise in COVID-19 JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 2472 DO 10.1183/13993003.congress-2022.2472 VO 60 IS suppl 66 A1 G Steinhilber A1 I Vogiatzis A1 B Salvi A1 L Bertacchini A1 I Favero A1 M Venturelli A1 M Paneroni A1 M Vitacca YR 2022 UL http://erj.ersjournals.com/content/60/suppl_66/2472.abstract AB Aim: We assessed safety of high-intensity [IV1] constant-load exercise (CLE) and intermittent exercise (HIIT) in 14 post-severe-COVID-19 patients (63±13 years; 78.6% male; BMI: 28±5, without comorbidities) between July 2020 and April 2021 after 55±22 days of COVID-induced acute respiratory failure.Methods: The crossover study balanced exercise intensity between CLE at 70% of peak work rate (WRpeak) to the limit of tolerance (Tlim) and HIIT including 1 min exercise at 100% WRpeak, alternated with 1 min at 40% WRpeak to Tlim. Gas exchange, ventilation, electrocardiography and symptoms were assessed.Results: Exercise endurance time and total work output were not different between HITT and CLE (Table 1). At Tlim, none of the ventilatory or cardiovascular responses differed between HITT and CLE and there was no difference in the intensity of symptoms (Table 1).View this table:Conclusions: Individuals with ongoing symptomatic COVID-19 could safely undertake high intensity exercise performed continuously or intermittently.FootnotesCite this article as Eur Respir J 2022; 60: Suppl. 66, 2472.This article was presented at the 2022 ERS International Congress, in session “-”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).