How Muscle Weakness Affects Breathing and Exercise in Lung Disease

Plain-English translation of NCT03800017 on ClinicalTrials.gov ↗ · Source last updated May 2026 · Translation generated June 2026 · How we translate trials

This study doesn't follow the usual testing phases — it may be an observational study or a different type of research.

What is this trial?

This study is investigating how skeletal muscle function contributes to shortness of breath and exercise difficulties in people with interstitial lung disease (a group of lung conditions involving inflammation or scarring). Researchers will compare muscle function between people with lung disease and healthy volunteers, and will test whether supplemental oxygen during exercise helps reduce fatigue and breathlessness.

People with interstitial lung disease often experience severe shortness of breath during physical activity, which greatly impacts their quality of life. Doctors have noticed that muscle weakness may be part of the problem, but this hasn't been thoroughly studied. This research aims to understand whether weak muscles contribute to exercise intolerance, and whether giving extra oxygen during activity can help.

Do you qualify?

You likely qualify if…

you are between 40 and 80 years old
you have been diagnosed with interstitial lung disease (such as idiopathic pulmonary fibrosis, hypersensitivity pneumonitis, or similar conditions)
you have fibrosis visible on a lung imaging scan (HRCT)
you are able to walk at least 50 meters in a 6-minute walk test
your oxygen level is at least 92% while at rest breathing normal air
you are clinically stable and have not had significant changes in your condition over the past 6 weeks

You likely don't qualify if…

you have a serious heart, bone, or nerve condition that would make exercise unsafe
you have other major health problems that could affect your ability to exercise
your lung function is severely reduced (FVC less than 50% or DLCO less than 25%)
you have recently completed or are currently in a pulmonary rehabilitation program (within the last 6 months)
you are taking high-dose prednisone (more than 10 mg per day for more than 2 weeks in the past 3 months)

What participation looks like

You would attend multiple visits where you complete exercise tests on a stationary bike or similar equipment while researchers measure your muscle function, oxygen levels, and how short of breath you feel. During some visits you'll exercise breathing normal air, and during others you'll breathe supplemental oxygen to see if it makes a difference in how you feel. The study involves physical testing and measurements, but no medications to take home.

AI-generated summary from trial data · Jun 17, 2026 · Not medical advice

Trial locations(1 site)

Canada

St. Paul's Hospital, Vancouver, British Columbia