Related Experiment Video
Updated: Jul 9, 2026
Dual Test Gas Pulmonary Diffusing Capacity Measurement During Exercise in Humans Using the Single-Breath Method
Published on: February 2, 2024
Comparison of oxygenation in peripheral muscle during submaximal aerobic exercise, in persons with COPD and healthy,
Krista G Austin1, Larry Mengelkoch, Jennifer Hansen
1Florida State University, Department of Nutrition, Food and Exercise Science, Tallahassee, FL, USA. krista.austin@eis2win.co.uk
Objective:
The purpose of this study was to compare peripheral muscle oxygenation in persons with chronic obstructive pulmonary disease (COPD) to healthy control persons, during submaximal exercise.
Methods:
Eight persons with COPD (forced expiratory volume in one second [FEV1] = 1.00 +/- 0.27 L) and eight healthy control persons (FEV, = 1.88 +/- 0.55L) performed a submaximal graded exercise test (GXT), and completed 4 min of constant load exercise (CON) at 50% of peak GXT. Measurements included oxygen uptake, heart rate, arterial oxygen saturation and peripheral muscle oxygenation (%StO2) at rest, during exercise, and recovery.
Results:
Significantly greater workloads were attained for controls compared with COPD for peak GXT and CON. No significant differences in %StO2 were observed between groups at: rest (GXT: 29.5 +/- 22.8 vs 30.4 +/- 17.3%; CON: 33.3 +/- 15.4 vs 35.1 +/- 17.2%); peak GXT (29.4 +/- 19.4 vs 26.5 +/- 15.9%); 4 min of CON (25.9 +/- 13.5 vs 34.5 +/- 21.8%); and recovery (GXT: 46.6 +/- 29.1 vs 44.3 +/- 21.7%; CON: 40.9 +/- 21.5 vs 44.5 +/- 23.2%).
Conclusion:
These results suggest that peripheral skeletal muscle oxygenation is not compromised in COPD during submaximal exercise, and limitations in exercise capacity are most likely a result of muscle disuse and poor lung function.
Related Concept Videos
01:23Physiological Control of Respiration
Breathing, a seemingly passive process, is regulated by the respiratory center in the brainstem. This center coordinates the involuntary control of respirations, which means it occurs without conscious effort, ensuring a smooth and uninterrupted pattern.
Regulation of Ventilation
The body maintains ventilation by monitoring levels of carbon dioxide (CO2), oxygen (O2), and hydrogen ion concentration (pH) in the arterial blood. Among these factors, the level of CO2 plays a crucial...
01:27Oxygen Transport in the Blood
01:19Special considerations while measuring oxygen saturation
Ensuring accuracy in vital sign recordings while prioritizing patient comfort and minimizing anxiety is important.
01:20Respiration and Gaseous Exchange
Respiration involves the exchange of gases, especially oxygen (O2) and carbon dioxide (CO2), between the alveoli and body cells, a process facilitated by blood circulation. As a result, the cardiovascular system, which involves the...
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...
01:27Chronic Obstructive Pulmonary Disease-IV: Assessement and Diagnostic Studies
Medical History