CClinicalTrials.gg
CompletedNCT05849168Updated Jan 29, 2026Results posted

High-Intensity Interval Training to Improve Symptoms of Deployment-Related Respiratory Disease

An interventional study of Exercise training in Occupational Exposure, sponsored by University of Colorado, Denver. Completed at 2 sites in United States. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-01-29.

Sponsored by University of Colorado, Denver · Not applicable, Interventional, and Treatment

Phase
Not applicable
Study type
Interventional
Enrollment
12
Allocation
Not applicable
Ages
18 Years to 65 Years
Sex
All
01

Study summary

Some military personnel who have been exposed to burn pit emissions, desert dust, and other airborne hazards experience new respiratory symptoms after deployment. The goal of this clinical trial is to learn about exercise in veterans with new respiratory symptoms after deployment to Southwest Asia. The main questions it aims to answer are:

  1. Do veterans with new respiratory symptoms after deployment have heart or lung abnormalities that contribute to difficulty exercising?
  2. Does high-intensity interval training (HIIT) improve fitness and symptoms?

Study participants will complete the following:

  1. Study Visits 1A and 1B: Exercise test (VO2max test), echocardiogram (heart ultrasound), blood tests, questionnaires
  2. Exercise program: 12 weeks of 3x/week supervised HIIT on upright stationary bicycle (\~40 minutes each) and 3x/week home aerobic exercise (45 minutes each)
  3. Study Visits 2A and 2B: Exercise test (VO2max test), echocardiogram (heart ultrasound), blood tests, questionnaires
02

Conditions studied

  • Occupational Exposure

Keywords

  • exercise tolerance
  • exercise therapy
  • airborne hazards
  • deployment-related respiratory disease
  • veterans
  • burn pit
03

In context

Lead sponsor

University of Colorado, Denver is the lead sponsor of 1,499 studies on the registry; 315 are open to participants now.

Of its 139 completed or terminated interventional studies of FDA-regulated products, 89 (64%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • Deployment of ≥30 days to Iraq, Afghanistan, Kuwait, Saudi Arabia, Bahrain, Qatar, United Arab Emirates, Kyrgyzstan, or Djibouti after September 2001
  • New onset of cough, shortness of breath, chest tightness/wheezing, dyspnea on exertion or exercise intolerance which started during or after deployment
  • Definite or probable distal lung disease (≥1 hyperinflation, emphysema, bronchiolitis, small airways inflammation, peribronchiolar fibrosis, or granulomatous pneumonitis on surgical lung biopsy; or ≥2 centrilobular nodularity, air trapping, mosaicism, or bronchial wall thickening on chest computed tomography [CT]), definite or probable deployment-related asthma (≥1 increase in post-bronchodilator forced expiratory volume in 1 second [FEV1] ≥12% and ≥200cc, or methacholine challenge with provocation concentration causing a 20% decline in FEV1 [PC20] ≤16 mg/mL), or unexplained dyspnea on exertion or exercise intolerance despite noninvasive testing including pulmonary function testing, methacholine challenge, transthoracic echocardiography, and/or chest computed tomography
  • Current symptoms of dyspnea on exertion or exercise intolerance
  • Residence \<90 miles from Rocky Mountain Regional VA and ability / willingness to attend in-person HIIT sessions and research visits
  • Vaccinated against Coronavirus-19 including primary series and (if eligible) ≥1 booster

Exclusion criteria

Exclusion Criteria:

  • Active / uncontrolled cardiovascular or pulmonary disease (e.g. hypertension with blood pressure >160/100 despite antihypertensive therapy, known hypertensive response to exercise [systolic blood pressure >220 mmHg in men / >190 mmHg in women], coronary artery disease, left ventricular ejection fraction ≤45% or heart failure with preserved ejection fraction with ongoing symptoms despite diuretic therapy, uncontrolled arrhythmia, moderate or severe valvular abnormality, diabetes with HbA1c >8.5%, asthma exacerbation requiring steroids within 4 weeks of enrollment, interstitial lung disease, untreated severe obstructive sleep apnea)
  • Pre-deployment history of cardiovascular or pulmonary disease including coronary artery disease, left ventricular ejection fraction ≤45% or heart failure with preserved ejection fraction requiring diuretic therapy, arrhythmia, valvular abnormality, chronic obstructive pulmonary disease, asthma (excluding childhood asthma that did not persist into adulthood), interstitial lung disease, or pulmonary hypertension
  • Body mass index \<18.5 or >45
  • Anemia with hemoglobin \<10 g/dl
  • Disorders that adversely influence exercise ability (e.g. arthritis or peripheral vascular disease)
  • Current fitness program (e.g. >30 minutes at metabolic equivalents [METs] >6 3 times/week or more)
  • Pregnancy or possible anticipated pregnancy during study duration
  • Post-menopausal status in women
05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
12 participants (actual)

Study arms

  • Experimental
    Veterans with respiratory symptoms

    Behavioral: Exercise training

Interventions

  • BehavioralExercise training

    Participants will complete a 12-week exercise training program. The program consists of 3x/week HIIT sessions on an upright stationary bicycle (\~40 minutes each) and 3x/week home aerobic sessions (any type of aerobic exercise; 45 minutes each).

06

What researchers measure

Primary outcomes

  1. Maximum Oxygen Consumption (VO2max)

    Obtained via metabolic cart during maximal cardiopulmonary exercise testing, in ml/kg/min

    Time frame: Up to 1 hour

  2. Health-related Quality of Life by Short Form 36 (SF-36) Questionnaire

    Units, Range 0-100 with higher scores indicating more favorable health state

    Time frame: Up to 1 hour

Secondary outcomes

  1. Left Ventricular Ejection Fraction Measured by Transthoracic Echocardiogram

    %

    Time frame: Up to 1 hour

  2. Tricuspid Annular Plane Systolic Excursion Measured by Transthoracic Echocardiogram

    mm

    Time frame: Up to 1 hour

  3. Plasma Acylcarnitine 10:0 Measured by Peripheral Venous Metabolomics (Ultra-high Performance Liquid Chromatography Coupled to Mass Spectrometry)

    Relative ion count

    Time frame: Up to 1 hour

  4. Feasibility of Exercise Program, Reported by Participant and Measured by Responses to Questionnaire

    Score, Likert scale indicating agreement with the statement "I was able to complete the scheduled high-intensity interval training sessions," 5-point range from 1 = "Strongly disagree" to 5 = "Strongly agree" with "Strongly agree" indicating greater agreement

    Time frame: Up to 1 hour

07

Results

Posted Jan 29, 2026

Participant flow

Participant flow — Overall Study
MilestoneVeterans With Respiratory Symptoms
Started12
Completed11
Not completed1

Outcome measures

PrimaryMaximum Oxygen Consumption (VO2max)

Obtained via metabolic cart during maximal cardiopulmonary exercise testing, in ml/kg/min

Time frame:
Up to 1 hour
Reported as:
Median · ml/kg/min
Maximum Oxygen Consumption (VO2max)
ml/kg/minVeterans With Respiratory Symptoms
Maximum Oxygen Consumption (VO2max)26.4 (23.8 to 28.9)
PrimaryHealth-related Quality of Life by Short Form 36 (SF-36) Questionnaire

Units, Range 0-100 with higher scores indicating more favorable health state

Time frame:
Up to 1 hour
Reported as:
Median · Units on a scale, Range 0-100
Health-related Quality of Life by Short Form 36 (SF-36) Questionnaire
Units on a scale, Range 0-100Veterans With Respiratory Symptoms
Health-related Quality of Life by Short Form 36 (SF-36) Questionnaire67 (44 to 79)
SecondaryLeft Ventricular Ejection Fraction Measured by Transthoracic Echocardiogram

%

Time frame:
Up to 1 hour
Reported as:
Median · % of blood
Left Ventricular Ejection Fraction Measured by Transthoracic Echocardiogram
% of bloodVeterans With Respiratory Symptoms
Left Ventricular Ejection Fraction Measured by Transthoracic Echocardiogram60 (58 to 63)
SecondaryTricuspid Annular Plane Systolic Excursion Measured by Transthoracic Echocardiogram

mm

Time frame:
Up to 1 hour
Reported as:
Median · mm
Tricuspid Annular Plane Systolic Excursion Measured by Transthoracic Echocardiogram
mmVeterans With Respiratory Symptoms
Tricuspid Annular Plane Systolic Excursion Measured by Transthoracic Echocardiogram26 (21 to 29)
SecondaryPlasma Acylcarnitine 10:0 Measured by Peripheral Venous Metabolomics (Ultra-high Performance Liquid Chromatography Coupled to Mass Spectrometry)

Relative ion count

Time frame:
Up to 1 hour
Reported as:
Median · Relative ion count
Plasma Acylcarnitine 10:0 Measured by Peripheral Venous Metabolomics (Ultra-high Performance Liquid Chromatography Coupled to Mass Spectrometry)
Relative ion countVeterans With Respiratory Symptoms
Plasma Acylcarnitine 10:0 Measured by Peripheral Venous Metabolomics (Ultra-high Performance Liquid Chromatography Coupled to Mass Spectrometry)4448588 (3488443 to 7035835)
SecondaryFeasibility of Exercise Program, Reported by Participant and Measured by Responses to Questionnaire

Score, Likert scale indicating agreement with the statement "I was able to complete the scheduled high-intensity interval training sessions," 5-point range from 1 = "Strongly disagree" to 5 = "Strongly agree" with "Strongly agree" indicating greater agreement

Time frame:
Up to 1 hour
Reported as:
Median · Scores on a Likert scale, 5-point range
Feasibility of Exercise Program, Reported by Participant and Measured by Responses to Questionnaire
Scores on a Likert scale, 5-point rangeVeterans With Respiratory Symptoms
Feasibility of Exercise Program, Reported by Participant and Measured by Responses to Questionnaire5 (4 to 5)

Adverse events

Collected over From enrollment until end of follow-up, up to 4 months. Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Veterans With Respiratory Symptoms0/12 (0%)0/12 (0%)0/12 (0%)

Baseline characteristics

Age, Continuous
Age, Continuous(Years)Veterans With Respiratory Symptoms
Mean46 ± 11
Sex: Female, Male
Sex: Female, Male(Participants)Veterans With Respiratory Symptoms
Female0
Male12
Race (NIH/OMB)
Race (NIH/OMB)(Participants)Veterans With Respiratory Symptoms
American Indian or Alaska Native1
Asian1
Native Hawaiian or Other Pacific Islander0
Black or African American2
White7
More than one race0
Unknown or Not Reported1
Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)Veterans With Respiratory Symptoms
Hispanic or Latino1
Not Hispanic or Latino11
Unknown or Not Reported0
08

Study locations

2 sites
  • University of Colorado Anschutz Medical Campus
    Aurora, Colorado 80045, United States
  • VA Eastern Colorado Health Care System
    Aurora, Colorado 80045, United States
09

References and documents

Study documents

  • Protocol and statistical analysis plan · Feb 1, 2024
  • Informed consent form · Mar 1, 2024

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: No

10

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Jan 29, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
11

Registry details

Key details

Study ID
NCT05849168
Lead sponsor
University of Colorado, Denver
Collaborators
VA Office of Research and Development
Responsible party
Sponsor
First posted
May 8, 2023
Start date
Nov 27, 2023
Primary completion
Jul 31, 2024
Completion
Jul 31, 2024
Results posted
Jan 29, 2026
Last update
Jan 29, 2026

Study contacts

William Cornwell, MD, MSCS
principal investigator · University of Colorado, Denver
Lindsay Forbes, MD
principal investigator · University of Colorado, Denver
Silpa Krefft, MD
principal investigator · VA Eastern Colorado Health Care System

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion