Related Experiment Video
Updated: Aug 5, 2026
Home-Based Prescribed Pulmonary Exercise in Patients with Stable Chronic Obstructive Pulmonary Disease
Published on: August 24, 2019
Cardiopulmonary Exercise Testing in Patients With Long COVID: Evaluating Functional Capacity and Exercise Limitations
Lotte Sørensen1, Camilla Lundgren Pedersen2, Mads Jønsson Andersen3
1Department of Physiotherapy and Occupational Therapy, Aarhus University Hospital, Aarhus, Denmark.
Background:
After COVID-19, some patients present with ongoing symptoms (eg, breathlessness, exercise limitations), even after mild acute infection.
Research Question:
What is the exercise capacity of patients diagnosed with long COVID and does it change from baseline to 1-year follow-up?
Study Design And Methods:
This retrospective case series included patients with persistent symptoms after a confirmed diagnosis of COVID-19. Exercise capacity was examined by cardiopulmonary exercise testing (CPET), and parameters related to performance, ventilation, circulation, and gas exchange were compared with predicted values. A subgroup of patients was retested 1 year after baseline, and self-reported physical fitness was assessed at follow-up.
Results:
In total, 169 patients completed baseline CPET and 41 patients completed 1-year follow-up. Mean maximum workload was 172 W (95% CI, 161-182), with 19% not achieving at least 84% predicted workload. Mean peak oxygen uptake was 24.4 mL/kg/min (95% CI, 23.1-25.7), and 36% had a value below % predicted. Oxygen uptake/workload slope below the normal threshold of 8.4 mL/min/W was observed in 54% of patients. The 1-year follow-up results showed no statistically significant changes in any of the CPET parameters, which correspond to lack of improvement in self-reported physical fitness.
Interpretation:
Patients with long COVID demonstrated lowered peak oxygen uptake, oxygen uptake/workload slope, and/or ventilatory equivalent for carbon dioxide, but different parameters were lowered in different patients, illustrating a heterogeneous study population. No improvements in any parameters were found at 1-year follow-up.
Related Concept Videos
01:27Chronic Obstructive Pulmonary Disease-IV: Assessement and Diagnostic Studies
Medical History
01:20Chronic Obstructive Pulmonary Disease-I: Introduction
01:26Exercise Stress Test
Exercise stress testing, commonly known as a treadmill test, is a noninvasive procedure used to evaluate cardiovascular function and diagnose heart conditions.
Definition
An exercise stress test measures the heart's response to exertion using a treadmill or stationary bicycle. Chest electrodes record the heart's electrical activity through an ECG, and blood pressure is monitored regularly.
Purposes
01:24Chronic Obstructive Pulmonary Disease
Smoking is a primary risk factor for COPD, with over 80% of patients having a history of it. Patients typically experience progressive dyspnea or labored breathing, frequent coughing, and recurrent pulmonary infections. Many eventually succumb to respiratory failure, characterized by...
01:25Chronic Obstructive Pulmonary Disease-III: Symptoms and Complications.
Symptoms of COPD can be classified as primary or systemic. Primary symptoms relate to reduced airflow, while systemic or extrapulmonary symptoms relate to COPD's broader impact on the body.
Primary Symptoms of COPD:
01:25Pulmonary Function Tests
Pulmonary Function Tests are crucial diagnostic tools for assessing respiratory function, particularly in patients with chronic respiratory disorders. They comprehensively evaluate lung volumes, ventilatory function, breathing mechanics, diffusion, and gas exchange. These tests help diagnose pulmonary diseases and play a significant role in monitoring disease progression, evaluating disability, and assessing response to therapy.
PFTs involve using a spirometer, a...