An interventional study of Therapeutic calf stretching and Sham calf stretching in Peripheral Artery Disease (PAD) and Intermittent Claudication, sponsored by Penn State University. Not yet recruiting at 2 sites in United States. Open to participants aged 50 Years and older. Per ClinicalTrials.gov, last updated 2026-11-05.
Sponsored by Penn State University · Not applicable, Interventional, and Treatment
The goal of this multi-center clinical trial is to assess the effects of passive calf muscle stretching in older adults diagnosed with peripheral artery disease (PAD). The main questions it aims to answer are:
Participants will use inflatable ankle stretch boots for 30 minutes a day, 5 days a week for 4-weeks
Patients with peripheral artery disease will passively stretch their calf muscles using a stretch device on both feet while seated for 30 minutes a day for 4 weeks at home. Peak treadmill walk time, calf macro- and micro-vascular function, walking gait pattern, and daily physical activity will be measured at baseline, 4 weeks, and 6 months.
309 studies on the registry are indexed under Intermittent Claudication; 46 are open to participants now.
This study's planned enrollment of 300 is above the median of 74 across 242 interventional studies indexed under Intermittent Claudication.
Browse Intermittent Claudication studies →Penn State University is the lead sponsor of 270 studies on the registry; 53 are open to participants now.
Of its 15 completed or terminated interventional studies of FDA-regulated products, 11 (73%) have results posted.
Compared within Intermittent Claudication, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Peripheral Arterial Disease. The counts are of registry records indexed under each term, refreshed daily. How we classify →
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
LVEF (left ventricular ejection fraction)
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
COPD
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Seated bilateral static calf stretching at 90% of maximal tolerated stretch intensity with both feet resting on a second chair (knees extended). This will be performed at home 30 minutes per day, 5 days per week, for 4 weeks.
Behavioral: Therapeutic calf stretching
Seated bilateral static calf stretching at a minimal stretch intensity with both feet resting on the floor (knees bent). This will be performed at home 30 minutes per day, 5 days per week, for 4 weeks.
Behavioral: Sham calf stretching
Participants will wear calf stretch boots for 4 weeks (30 minutes per day, 5 days per week) at 90% of maximal tolerable stretch.
Participants will wear calf stretch boots for 4 weeks (30 minutes per day, 5 days per week) at approximately 10% of maximal tolerable stretch.
Change in peak treadmill walking distance
Change from baseline in continuous walking distance (meters) during the treadmill walking test protocol
Time frame: Baseline, 4 weeks, and 24 weeks
Change in calf muscle microvascular function
Change from baseline in calf muscle re-oxygenation (%SmO2) after the 5 minute vascular occlusion test
Time frame: Baseline, 4 weeks, and 24 weeks
Change in peak normalized average forefoot force during a self-selected walking pace
Change from baseline in ground reaction force during a self-selected level ground walking pace
Time frame: Baseline, 4 weeks, and 24 weeks
Plan to share: Yes — IPD will be shared under controlled-access conditions. De-identified individual participant data from published results will be made available to qualified researchers upon reasonable request and following completion of an appropriate data use agreement.
Supporting information: Study protocol, Informed consent form
Time frame: Start date will be one year after completion of primary data collection (December 2032). End date will be December 2035 (3 years after completion of primary data collection).
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions 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.