Submaximal and maximal exercise tests in the follow up of severe Covid-19

ABSTRACT

Background: One-minute sit and stand test (1STST) is a very feasible test of functional capacity. The maximal cardiopulmonary exercise test (CPET) is more complex and comprehensive to evaluate exercise capacity. These tests might have different responses in the late recovery of patients with Covid-19. Aim(s) Identify the persistence of capacity limitation through 1STST and CPET at 30 and 90 days after the onset of symptoms in patients who had a severe and critical illness from Covid-19. Our hypothesis is that 1STST is a submaximal test limited by time and may not detect exercise capacity limitation in some patients. Method(s) Prospective study involving 17 patients with severe Covid-19. The time of the first 5 repetitions and the number of repetitions in 60 seconds in 1STST were used to identify lower performance. Maximal CPET on the cycle was performed and peak VO <= 83% pred was used to confirm lower performance. Result(s) The 1STST was considered submaximal and identified 52% of the patients with greater time than expected to perform 5 repetitions in 30 days, and only 11.8% in 90 days. The number of repetitions in 60 sec was reduced by 58.8% at 30 days and persists this reduction by 11.8% at 90 days (table). CPET identified a much lower performance of 58.8% mainly after 90 days. Conclusion(s) Both tests had different responses in the magnitude of recovery from 30 to 90 days after severe Covid-19. There is a substantial proportion of patients who are potentially impaired and improved in 1STST but not in CPET.