Research

Mixed

SARS-CoV-2 infection is associated with a significant reduction in exercise capacity (peak VO2), particularly in individuals with Long COVID symptoms, with mechanisms including deconditioning, dysfunctional breathing, chronotropic incompetence, and impaired peripheral oxygen extraction.

If you have Long COVID and feel exhausted by activity, standard 'push through it' advice may be harmful. Get a Cardiopulmonary Exercise Test (CPET) to identify if your limitation is due to deconditioning, heart rate issues (chronotropic incompetence), or breathing problems. Treatment should be tailored to the specific mechanism found, rather than generic exercise.

ModerateSupportsLOW confidence
By meta-analysis of 9 studies including 404 infected versus uninfected individuals, peak VO2 was 7.4 ml/kg/min (95%CI 3.7 to 11.0) lower among infected versus uninfected individuals... peak VO2 was 4.9 ml/kg/min (95%CI 3.4 to 6.4) lower compared to those without symptoms. Deconditioning was common, but dysfunctional breathing, chronotropic incompetence, and abnormal oxygen extraction were also described.
Matthew S. Durstenfeld et al. · JAMA Network Open · 2022

Why this rating

Meta-analysis of observational studies with high heterogeneity and selection bias (mostly hospitalized/symptomatic cohorts).

Source

Use of Cardiopulmonary Exercise Testing to Evaluate Long COVID-19 Symptoms in Adults

Matthew S. Durstenfeld et al. · JAMA Network Open · 2022

DOI 10.1001/jamanetworkopen.2022.36057

Meta-analysis · 39 studiesCited 181×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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