Exercise Intolerance in Post-COVID Patients

The post-COVID syndrome poses an unprecedented challenge to modern society, affecting millions of people worldwide. Persistent fatigue and exercise intolerance are among the most common complaints of these subjects. The mechanisms of exercise intolerance in post-COVID subjects are remained yet unknown, which make the rehabilitation efforts complex and challenging. The overall goals of this project are to: 1) improve physiological understanding of symptoms in this clinical condition, 2) elucidate plausible mechanisms to explain exercise intolerance/symptom exacerbation, and finally 3) provide knowledge that can be directly applied in the clinical setting to improve diagnosis, care, and individualized rehabilitation of subjects with post-COVID syndrome. Post-COVID subjects and age/sex matched healthy controls will undertake a comprehensive set of physiological and functional assessments, followed by 3 experimental visits (in a randomized order), where acute exercise responses will be assessed in either continuous moderate intensity aerobic exercise, high intensity interval exercise, or strength training. The same set of physiological assessments will also be performed after 1 year in both post-COVID subjects and healthy-matched controls to better understand the time course of the syndrome. It is hypothesized that the mechanism responsible for exercise intolerance is linked to specific symptoms and will vary across subjects. However, it is expected that most post-COVID subjects will respond well to at least one type of exercise.