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Introduction: Studies have demonstrated a reduction in peak oxygen consumption (VO 2 ) post-acute COVID-19. We sought to determine the association between acute COVID-19 severity, post-acute symptoms and peak VO 2 after recovery. Methods: This study analyzed data from patients who recovered from COVID-19 and underwent cardiopulmonary exercise testing (CPET) as part of prospective studies in 5 centers across UK and Europe. Patients were asked to report current symptoms. Peak VO 2 , lung volumes, gas exchange, ventilatory efficiency, heart rate and O 2 pulse were measured in a standard symptom-limited incremental cycle ergometer CPET. Results: Among 417 patients examined 136±63 days after recovery from COVID-19, 164 (39%) were female. Mean age was 56.9±13.3 years. The spectrum of acute COVID-19 severity included critical (N=47; 11.3%), severe (180; 43.2%), moderate (75; 18.0%) and mild (115; 27.5%) illness. The most common post-acute symptom was dyspnea (200; 48%), followed by muscle pain (173; 41%). Mean peak respiratory exchange ratio was 1.13±0.1, and did not vary across acute disease severity or post-acute symptom status. There was no significant difference in peak VO 2 as % from predicted in mild to critical acute disease: 84.0±2.1%, 91.4±2.6%, 82.9±1.7% and 83.7±3.2%, respectively (p=0.06). Patients with dyspnea or muscle pain had each lower peak VO 2 as % from predicted, compared to patients free of the specific symptom (81.3±21.2% vs. 88.1±22.9%, p=0.002 and 78.6±19.1% vs. 88.2±22.0%, p<0.0001, respectively). Both dyspnea and muscle pain were each associated with significantly lower peak heart rate and peak O 2 pulse, as well as lower lung volumes and gas exchange capacity, compared to patients free of the specific symptom. Conclusions: Common post-acute COVID-19 symptoms, and not acute disease severity, are associated with lower peak VO2 in CPET. Parameters related to both cardiac and pulmonary function seem to play a role in this reduced physical performance.