NCT06389149 · University of Nebraska
Leg Exercise Assistive Paddling (LEAP) Therapy for Peripheral Artery Disease
What this study is about
The purpose of this study is to test the effects of leg exercise assistive paddling (LEAP) therapy during prolonged sitting (PS) on vascular and functional performance in those with peripheral artery disease (PAD) and age-matched controls. LEAP therapy is a novel application of passive limb movement to enhance blood flow through the legs without muscular contractions.
View original scientific description
The purpose of this study is to test the effects of leg exercise assistive paddling (LEAP) therapy during prolonged sitting (PS) on vascular and functional performance in those with peripheral artery disease (PAD) and age-matched controls. LEAP therapy is a novel application of passive limb movement to enhance blood flow through the legs without muscular contractions. Specifically, LEAP therapy is the rotational passive movement of the lower leg about the knee from 90 to 180 degrees of rotation at a cadence of 1Hz. Previous literature has indicated that this movement pattern can produce robust increases in blood flow in the passively moved limb in healthy individuals, and passive limb movement may protect vascular function during PS. However, the impact of LEAP therapy to improve blood flow in the legs of those with PAD during PS is unknown. Participants will participate in a randomized cross-over design study with 2 visits (LEAP therapy and no LEAP therapy). For the first visit, participants will be randomly allocated to receive LEAP therapy during 2.5 hours of PS or not. For the second visit, participants will sit for 2.5 hours and will receive the condition that they did not previously receive. Before and after PS, the following measurements will be made: flow-mediated dilation of the popliteal and brachial arteries, arterial stiffness with tonometry techniques, microvascular vasodilatory capacity and skeletal muscle metabolic rate with near-infrared spectroscopy, autonomic nervous system function, and there will be blood drawn from the antecubital vein. After PS, participants will participate in a graded exercise test to assess functional walking capacity. Finally, during PS, near-infrared spectroscopy on the calf muscles and electrocardiogram will be collected continuously to monitor muscle oxygen availability and autonomic activity, respectively.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- PAD subjects:
- Able to provide written informed consent
- 50-85 years of age
- Diagnosed with Peripheral Arterial Disease (PAD) Fontaine stage II-III
- Women must be postmenopausal (cessation of menses for \> 24 months)
- History of exercise-induced claudication
- Free of ulcers, gangrene, or necrosis of the foot, Fontaine stage IV PAD Age-matched control subjects:
- Able to provide written informed consent
- 50-85 years of age
- No evidence of peripheral occlusive disease, ankle-brachial index \> 0.90
- Women must be postmenopausal (cessation of menses for \> 24 months)
Exclusion criteria
- PAD subjects:
- Pain at rest and/or tissue loss from Peripheral Arterial Disease (PAD), Fontaine stage IV PAD
- Acute lower extremity ischemic event secondary to thromboembolic disease or acute trauma
- Limited walking capacity from conditions other than PAD
- Have not had a physical exam to assess exercise limitations in the past year
- Pregnant or nursing
- Kidney disease or type II diabetes mellitus Age-matched control subjects:
- Positive diagnosis of Peripheral Arterial Disease (PAD)
- Any exercise limitations as determined at last physical exam, at least 1 year prior to study
- Have not had a physical exam to assess exercise limitations in the past year
- Limited walking capacity from musculoskeletal injury
- Pregnant or nursing
- Kidney disease or type II diabetes mellitus
Where
- Omaha, Nebraska
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Oct 1, 2025 · Source of record for eligibility and locations