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NCT04679402 · ClinicalTrials.gov registry record · NA
Diaphragm Function and Diver Endurance
A NA study of Respiratory Muscles, sponsored by Duke University.
- Completed
- Registry status
- NA
- Development phase
- 45
- Enrollment target
- 1
- Study location
NCT04679402: Completed NA study of Respiratory Muscles, sponsored by Duke University.
NCT04679402 is a NA study of Respiratory Muscles that has completed, run by Duke University. The registered enrollment target is 45 participants, below the 1,404-participant average among 58,714 other NA trials with a reported enrollment target (97% lower). The trial reports 1 study location across 1 state. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04679402, a NA study of Respiratory Muscles, has completed, sponsored by Duke University.
- COMPLETED
- Registry status
- NA
- Development phase
- 45 participants
- Enrollment target
- 1
- Study location
Study Summary
This project will test the following hypotheses: 1. Training of the inspiratory muscles increases underwater endurance and reduces hypercapnia in divers. 2. Inspiratory muscle training while breathing low concentration carbon monoxide (200 ppm) for 30 minutes daily improves diaphragm performance to a greater degree than the same training breathing air. 3. Inspiratory muscle training increases hypercapnia ventilatory response (gain) in those individuals with a low gain. 4. Variability in oxygen (O2) and carbon dioxide (CO2) permeability of erythrocyte membranes is a determining factor in underwater exercise performance.
Primary Outcome
Endurance during continuous underwater exercise at a depth of 50 ft below the surface
Conditions Studied
Interventions
- OTHER Carbon monoxide 200 ppm in air
Study Locations (1)
North Carolina
- Duke University Medical Center - Durham
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 45 participants |
| Start Date | 2022-04-14 |
| Est. Completion | 2024-04-30 |
| Phase | NA |
What the finished NCT04679402 record still lists
NCT04679402 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 45 participants, a relatively small participant target, below the 1,404-participant average among 58,714 other NA trials with a reported enrollment target (97% lower).
The record links to 1 condition, with Respiratory Muscles appearing as the primary indexed condition, and to 1 intervention - of which Carbon monoxide 200 ppm in air is the first listed.
NCT04679402 reports a single indexed study location in North Carolina.
Frequently Asked Questions
What is clinical trial NCT04679402 about?
NCT04679402 is a clinical study titled "Diaphragm Function and Diver Endurance". This project will test the following hypotheses: 1. Training of the inspiratory muscles increases underwater endurance and reduces hypercapnia in divers. 2. Inspiratory muscle training while breathing low concentration carbon monoxide (200 ppm) for 30 minutes daily improves diaphragm performance to...
What is the current status of trial NCT04679402?
This trial is currently completed. It is a NA study. The enrollment target is 45 participants. The study started on 2022-04-14. Estimated completion is 2024-04-30.
What conditions does trial NCT04679402 study?
This clinical trial studies the following conditions: Respiratory Muscles.
What interventions are being tested in trial NCT04679402?
The interventions under investigation include: Carbon monoxide 200 ppm in air (OTHER).
Who is sponsoring clinical trial NCT04679402?
This trial is sponsored by Duke University, which has 1,725 total clinical trials registered on ClinicalTrials.gov.
Where is trial NCT04679402 being conducted?
This trial has 1 study location across North Carolina. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT04679402's enrollment target sits among peer trials
45 1411th of 2000 higher than 578 of 2,000 other NA trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other NA trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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