Recruiting

Oxygen-guided Exercise

Sponsor:

VA Office of Research and Development

Code:

NCT06003855

Conditions

Peripheral Artery Disease

Eligibility Criteria

Sex: All

Age: 0+

Healthy Volunteers: Not accepted

Interventions

Supervised exercise therapy

Study Details

Brief summary:

Peripheral artery disease (PAD) is a cardiovascular disease manifesting from systemic atherosclerosis, which blocks the leg arteries and results in insufficient blood flow to the lower extremities. Limb ischemia from PAD is the most common disorder treated within the vascular surgery service at the Omaha Veterans' Affairs Medical Center. PAD also accounts for one-third of the operations performed in the VA Medical Centers nationwide. This project aims to establish the feasibility and acceptability of a muscle oxygen-guided supervised exercise program for patients with PAD. The investigators will determine the potential benefits of using this intervention over standard supervised exercise therapy. This modified intervention may enable patients to increase overall physical activity without the negative impacts on muscle structure and function. Increasing physical activity will decrease cardiovascular morbidity and mortality. If proven beneficial, the findings will lead to an improved exercise program that directly benefits veterans nationwide.

Conditions

Peripheral Artery Disease

Study ID

NCT06003855

Start date

Oct 1, 2023

Status verified date

Jan, 2026

Completion date

Dec 30, 2026

Anticipated

Primary completion date

Dec 30, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 0+

Healthy Volunteers: Not accepted

Inclusion Criteria:

At entry into the study, all subjects must:

  • Be able to give written, informed consent
  • Have documented lower extremity arterial occlusive disease based on ankle/brachial index measurements and/or arterial imaging
  • Demonstrate positive history of chronic claudication
  • Have a stable blood pressure regimen, stable lipid regimen, stable diabetes regimen and risk factor control for 6 weeks

Exclusion Criteria:

Any potential subjects will be excluded if they have:

  • Rest pain or tissue loss due to PAD (Fontaine stage III and IV)
  • Acute lower extremity ischemic event secondary to thromboembolic disease or acute trauma
  • Walking capacity limited by conditions other than claudication including leg (joint/musculoskeletal, neurologic) and systemic (heart, lung disease) pathology

Study Design

Enrollment

12 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

experimental: Oxygen guided supervised exercise

Modified-SET parameters will be determined from resting StO2 during 10 minutes of sitting. The StO2 threshold will be set at 15% lower than baseline StO2 levels. After warm-up, the subjects will walk until they reach the StO2 threshold. The subjects will be instructed to stop walking once they reach the threshold and to rest until the StO2 level returns to the baseline level. Then, subjects will be instructed to begin walking again and this cycle will be repeated for 50 total minutes. The threshold was selected to be above the 31% drop associated with claudication onset time. If subjects experience pain earlier than the 15% drop, the threshold will be progressively decreased by 5%, as needed. Subjects will repeat this for up to 50 minutes (including walking and rest). Walking speed and treadmill incline will be adjusted to allow for 5-10 minutes of walking before reaching the threshold. Subjects will complete 3 sessions/week for 12 weeks.

active comparator: Standard supervised exercise

After the warmup, subjects will walk until claudication pain becomes severe and needs to stop. Then subjects will rest until claudication pain subsides. Afterwards, subjects will walk again, repeating the cycle for up to 50 minutes (including walking and rest). Walking speed and treadmill incline will be adjusted during the SET session to allow individuals with PAD to walk for 5-10 minutes before claudication symptoms arise. Time at each speed and incline, along with rest times will be recorded during each exercise session. Subjects will complete 3 sessions/week for 12 weeks.

Interventions

Supervised exercise therapy

Subjects will be enrolled in a 12-week intervention program of either modified supervised exercise therapy or standard supervised exercise therapy. The program will be 3 sessions/week for 12 weeks. Each session will consist of 50 minutes plus 5 minutes warm up and cool down.

Primary outcome measure

  • Distance walked [ Time Frame: Before and after 12 week exercise program ]
  • Energy expenditure [ Time Frame: Before and after 12 weeks after the exercise program ]
  • Reactive oxygen species [ Time Frame: Before exercise, immediately after exercise, 30 minutes after exercise, and 1 hour after exercise ]
  • Protein expression of ROS-related enzymes [ Time Frame: Before exercise, immediately after exercise, 30 minutes after exercise, and 1 hour after exercise ]
  • Markers of systemic inflammation [ Time Frame: Before exercise, immediately after exercise, 30 minutes after exercise, and 1 hour after exercise ]
  • Initial and absolute walking distances [ Time Frame: Before and after 12 week supervised exercise program ]
  • Comprehensive mitochondrial respiratory complex function [ Time Frame: Before and after 12 week supervised exercise program ]
  • Mitochondrial dynamics [ Time Frame: Before and after 12 week supervised exercise program ]
  • Mitochondrial reactive oxygen species production [ Time Frame: Before and after 12 week supervised exercise program ]

Central Contacts and Locations

Central contacts

Farahnaz Fallahtafti, PhD

(402) 995-3542ffallahtafti@unomaha.edu

Sara A Myers, PhD

(402) 554-3246Sara.Myers2@va.gov

Locations

Omaha VA Nebraska-Western Iowa Health Care System, Omaha, NE

Recruiting

Omaha, Nebraska, United States, 68105-1850

Contacts

Frederick G Hamel, PhD

402-995-3540Frederick.Hamel@va.gov

Amy M Patten

(402) 995-3541amy.patten@va.gov

Principal Investigator:

Iraklis I Pipinos, MD

More Information

Sponsor

VA Office of Research and Development

Last update posted

Jan 13, 2026

Last verified

Jan, 2026

Keywords

  • peripheral arterial disease
  • atherosclerosis
  • arterial occlusive disease
  • gait

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by VA Office of Research and Development on 2026-01-13.