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

High-Intensity Interval Training (HIIT) to Improve Symptoms of Deployment-Related Respiratory Disease - A Pilot Study

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

Study Overview

• Status: Completed
• Conditions: Occupational Exposure
• Intervention / Treatment: Behavioral: Exercise training

• Study Type: Interventional
• Enrollment (Actual): 12
• Phase: Not Applicable

Contacts and Locations

Study Locations

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

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

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:

• 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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Veterans with respiratory symptoms	Behavioral: Exercise 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).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Maximum Oxygen Consumption (VO2max)	Obtained via metabolic cart during maximal cardiopulmonary exercise testing, in ml/kg/min	Up to 1 hour
Health-related Quality of Life by Short Form 36 (SF-36) Questionnaire	Units, Range 0-100 with higher scores indicating more favorable health state	Up to 1 hour

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Left Ventricular Ejection Fraction Measured by Transthoracic Echocardiogram	%	Up to 1 hour
Tricuspid Annular Plane Systolic Excursion Measured by Transthoracic Echocardiogram	mm	Up to 1 hour
Plasma Acylcarnitine 10:0 Measured by Peripheral Venous Metabolomics (Ultra-high Performance Liquid Chromatography Coupled to Mass Spectrometry)	Relative ion count	Up to 1 hour
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	Up to 1 hour

Collaborators and Investigators

• Sponsor: University of Colorado, Denver
• Collaborators: VA Office of Research and Development
• Investigators: Principal Investigator: William Cornwell, MD, MSCS, University of Colorado, Denver; Principal Investigator: Lindsay Forbes, MD, University of Colorado, Denver; Principal Investigator: Silpa Krefft, MD, VA Eastern Colorado Health Care System

Study record dates

Study Major Dates

• Study Start (Actual): November 27, 2023
• Primary Completion (Actual): July 31, 2024
• Study Completion (Actual): July 31, 2024

Study Registration Dates

• First Submitted: April 17, 2023
• First Submitted That Met QC Criteria: May 5, 2023
• First Posted (Actual): May 8, 2023

Study Record Updates

• Last Update Posted (Actual): January 29, 2026
• Last Update Submitted That Met QC Criteria: January 12, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: exercise tolerance; veterans; exercise therapy; airborne hazards; deployment-related respiratory disease; burn pit
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Respiration Disorders; Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena; Exercise
• Other Study ID Numbers: 22-2069

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No