About 77 percent of patients admitted to COVID-19 were able to maintain their normal exercise capacities one years after their discharge the investigators wrote within the European Respiratory Journal.

This prospective investigation of people who were hospitalized for COVID-19 was designed to assess their cardiopulmonary fitness capacity after 12 months, measure the improvement from 3 months up to twelve months and then compare the results of patients post-COVID-19 with a group of healthy individuals who had not COVID-19.

The study was a substudy of patients who underwent an exercise test for cardiopulmonary (CPET) within 3 or 12 months of an Norwegian study called “Patient-Reported outcomes and Lung Function following admission to hospital for COVID-19” (PROLUN).

Participants in the study were aged 18 or older, and had COVID-19 as their discharge diagnosis on or before July 1, 2020 from six hospitals. Patients were invited to follow-up visits three and twelve months following their discharge. The treadmill exercise stepwise was utilized for CPET.

Controls with matched controls were recruited for the HUNT4 HOPE group that is part of the Norwegian population-based Trondelag Health study, in which CPET and echocardiography was performed on 2461 participants between 2017 and 2019.

The primary result was the peak oxygen uptake (VO 2peak). In the exercise intolerance test, it is defined as having a the VO 2peak less than 80% as predicted.

The major findings of this study were that majority of patients with COVID-19 were able to exercise normally after 12 months. Exercise intolerance decreased and the VO 2peak and oxygen pulse was improved between 3 and 12 months after hospitalization.

An overall of 177 people as well as the 207 controls were included in the study. Participants had a median (SD) average age of 58.1 (13.8) years and 41% of them were female. They had completed their 12-month follow-up visit with a median of 376 (309-472) days after discharge, and were admitted to hospital for a mean of 6 (3-11) hours. A modified Medical Research Council scale score (grade 0-4 and 0 meaning none of the dyspneas) was at or near 1 for 86 of the patients (47 percent) after 12 months, compared to the 89 patients (51 percent) after 3 months.

At 12 months after 12 months, an VO 2peak of less than 80% was predicted. was seen within 40 participants (23 percent) and circulatory impairments being observed in 11 patients (28 percent) with ventilatory restrictions in 7 (17 percent) patients, as well as various causes in 22 (55 percent) participants. More than 80% of the patients.

In the study, exercise intolerance was reported at 34% the participants after 3 months, versus 23 percent after 12 months. The VO 2peak and oxygen pulse lactate partial pressures of carbon dioxide (PCO 2) and the volume of oxygen (VO) 2. in the anaerobic threshold percent of predicted maximum volume oxygen (VO 2max) were significantly higher at 12 months, compared to 3 months post-discharge. The estimated rises of VO 2peak percentage predicted and VO 2 kg 1 percent predicted was 5.0 percent (pp) (95 percent 95% CI, 3.1-6.9) and 3.4 percent (95 percent C.I, 1.6-5.1), respectively.

After 12 months COVID-19 patients were found to have lower the VO 2peak (2451 vs 2952) and VO 2peak kg -1 (28.6 vs. 34.9) against the matched control group. COVID-19 patients also had lower cardiac rate, breath frequency as well as expired volumes (VE) in comparison to the matched group of control.

There were a variety of study limitations. all patients were admitted to hospitals in the beginning stage of the pandemic in which vaccines were not available. Additionally the control patients were not hospitalized and CPET was carried out using different protocols and equipment in the COVID-19 group and the control group with a similar matched.

“The major findings from this study was that the majority of patients with COVID-19 were able to exercise normally after 12 months. Exercise intolerance decreased and the VO 2peak and oxygen pulse increased between 3 and 12 months following hospitalization.” according to the study’s authors.

Disclosure: A few of the study authors have disclosed affiliations with pharmaceutical, biotech or device companies. Refer to the original reference for a complete list of disclosures made by authors.


Ingul CB, Edvardsen A, Follestad T, et al. Changes in the cardiopulmonary exercise capacity and limitations from 3 to 12 months following COVID-19. Eur Respir J. Published online September 22, 2022. doi:10.1183/13993003.00745-2022