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Chronic StrokeNCT06973590

Blood Flow Restriction and Transcutaneous Electrical Nerve Stimulation on Motor Function in Stroke

A study testing Blood flow restriction (BFR), Transcutaneous electrical nerve stimulation (TENS) and Low-intensity resistance training (LIRT) in people with Chronic Stroke, run by The Hong Kong Polytechnic University at 1 site in Hong Kong.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts
Official record
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Trial summary

Stroke commonly results in persistent leg impairments that limit mobility and reduce quality of life. This study investigates whether combining low-intensity resistance training with blood flow restriction (LIRT-BFR) and transcutaneous electrical nerve stimulation (TENS) can effectively improve leg function in stroke… Read more about this study

Who is it for?
Ages 50 to 80 years
Conditions the study is for
Chronic Stroke
What is being tested?
Blood flow restriction (BFR), Transcutaneous electrical nerve stimulation (TENS) and Low-intensity resistance training (LIRT)
Could I receive a placebo?
Yes, some participants may receive a placebo
How many people
60 participants
Where
1 siteHong Kong
Study dates
1 Sep 2024to 31 Dec 2026
Phase
Interventional
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 50 to 80 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • are between 50 and 80 years of age;
  • have had a single stroke more than 6 months and less than 15 years;
  • have at least 5 degrees of active ankle dorsiflexion in the antigravity position;
  • are able to walk 10 m independently, with or without a walking aid;
  • are able to score 6 or higher out of 10 on the abbreviated mental test;
  • have no skin allergies (e.g. redness or itchiness after application of the electrical stimulation pads) to electrical stimulation or electrodes;
  • are able to follow instructions and give informed consent.

Who cannot join

  • presence of other comorbidities like varicose veins, peripheral neuropathy, cancer, musculoskeletal injury, lower limb peripheral edema, post-surgical swelling, open wounds, or on a medication that increases blood clotting risk;
  • resting blood pressure ≥ 160/100 mmHg even after taking medications, cardiovascular comorbidity, heart failure, unstable angina, by-pass surgery, a pacemaker;
  • administration of botulinum toxin in the lower limb at least 6 months prior to training;
  • history of epilepsy, cochlear implants, any type of deep brain stimulator and metal implants in the head or neck;
  • currently not participating in resistance training or high-intensity or long duration cardiovascular exercise;
  • lack the ability to feel pain (because of paralysis), or other subjects who cannot complain of discomfort.

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

Hong Kong1 site, 1 recruiting
  • The Hong Kong Polytechnic University

    Hong Kong

    Shamay NG, PhD, +852 27664889, shamay.ng@polyu.edu.hk

    Recruiting

Other trials in Hong Kong

About this study

Official title: Effects of Low-intensity Resistance Training With Blood Flow Restriction and Transcutaneous Electrical Nerve Stimulation on Lower Limb Motor Function in People With Stroke

Stroke commonly results in persistent leg impairments that limit mobility and reduce quality of life. This study investigates whether combining low-intensity resistance training with blood flow restriction (LIRT-BFR) and transcutaneous electrical nerve stimulation (TENS) can effectively improve leg function in stroke survivors.

Participants with chronic stroke will be randomly assigned to one of four intervention groups: 1) LIRT with simulated BFR and simulated TENS; 2) LIRT with actual BFR and simulated TENS; 3) LIRT with simulated BFR and actual TENS; 4) LIRT with both actual BFR and actual TENS. The resistance training utilizes 20% of each participant's maximum lifting capacity. For blood flow restriction, an automated pressure cuff (SmartCuffs 4.0) will be placed on the upper portion of the affected leg, inflated to 50% of the individual's occlusion pressure during exercises and deflated during rest periods. TENS therapy delivers controlled electrical impulses through electrodes positioned on the anterior thigh.

Read more

Each 60-minute session includes a 10-minute warm-up followed by 40 minutes of targeted resistance exercises (leg extensions, leg presses, and weight-bearing squats) and concludes with 10 minutes of stationary cycling. The resistance protocol involves 3 sets of 20 repetitions with standardized rest intervals between sets and exercises. Participants will attend three sessions weekly for six weeks.

Assessments will be conducted at baseline, midpoint (3 weeks), completion (6 weeks), and follow-up (1 month post-intervention). The primary outcome measure is the Fugl-Meyer Assessment for Lower Extremity function, with secondary measures including muscle strength, stiffness, balance, mobility, walking capacity, and gait parameters. To understand the underlying mechanisms, we will measure muscle oxygenation using near-infrared spectroscopy, evaluate muscle structure via ultrasound, and monitor physiological responses including heart rate variability and perceived exertion for safety monitoring.

Read the detailed description

Stroke often leads to persistent lower-limb impairments, limiting functional recovery and quality of life. Low-intensity resistance training with blood flow restriction (LIRT-BFR) has shown promise in improving muscle function in healthy populations, but its effects in stroke rehabilitation remain underexplored. Additionally, while BFR and electrical stimulation have been beneficial for pain relief and muscle activation, the impact of combining BFR with transcutaneous electrical nerve stimulation (TENS) in stroke patients remains unknown. The objectives of this study is to evaluate whether a multi-mode exercise rehabilitation training program of LIRT-BFR and TENS can restore lower extremity strength, mobility, and quality of life.

In this randomized controlled trial, chronic stroke patients will be allocated to one of four groups: 1) LIRT + sham BFR + sham TENS, 2) LIRT + BFR + sham TENS, 3) LIRT + sham BFR + TENS, and 4) LIRT + BFR + TENS. The LIRT protocol utilizes 20% of one-repetition maximum (1-RM) as the standardized training load. BFR implementation involves an automated restriction band (SmartCuffs 4.0) positioned at the proximal region of the affected lower extremity, calibrated to 50% of the individual's lower limb occlusion pressure (LOP). The pressure system remains inflated throughout active training phases and is systematically deflated during inter-exercise intervals. TENS application targets the anterior thigh region.

The intervention protocol comprises a structured 60-minute session beginning with a 10-minute preparatory warm-up, followed by 40 minutes of targeted resistance exercises including leg extensions, leg presses, and load-bearing squats focused on the affected limb, concluding with 10 minutes of aerobic cycling. Each resistance exercise consists of 3 sets of 20 repetitions with rest intervals. The assessments will be conducted at baseline, mid-intervention (3 weeks), post-intervention (6 weeks), and follow-up (1 month post-completion).

The primary outcome measure will be the Fugl-Meyer Assessment Lower Extremity (FMA-LE) score, and secondary outcome measures including muscle strength, stiffness, balance, functional mobility, walking capacity, gait speed, etc. To elucidate the underlying mechanisms, the study will use near-infrared spectroscopy (NIRS) to assess muscle oxygenation and hemodynamics, ultrasound for muscle morphology, and exercise measures like heart rate variability (HRV) and rating of perceived exertion (RPE) for safety consideration.

Conditions
Chronic Stroke
Being tested
Blood flow restriction (BFR), Transcutaneous electrical nerve stimulation (TENS), Sham blood flow restriction (Sham-BFR), Sham transcutaneous electrical nerve stimulation (Sham-TENS), Low-intensity resistance training (LIRT)
Keywords
blood flow restriction, transcutaneous electrical nerve stimulation, stroke, low-intensity resistance training
Medical subject headings
Stroke

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Blood flow restriction (BFR)Device

    BFR implementation involves an automated restriction band (SmartCuffs 4.0) positioned at the proximal region of the affected lower extremity, calibrated to 50% of the individual's lower limb occlusion pressure (LOP). The pressure system remains inflated throughout active training phases and is systematically deflated during inter-exercise intervals.

  • Transcutaneous electrical nerve stimulation (TENS)Device

    TENS will be delivered to the anterior thigh region of the paretic leg using a 120z Dual-Channel TENS Unit (ITO Physiotherapy \& Rehabilittaion, Co, Ltd, Tokyo, Japan). The TENS stimulation will be at 100 Hz, with 0.2 ms square pulses at an intensity of twice the sensory threshold (defined as the minimum intensity at which subject reported feeling a tingling sensation and below the motor threshold as indicated by the absence of muscle twitching.

  • Sham blood flow restriction (Sham-BFR)Device

    Sham BFR implementation involves an automated restriction band (SmartCuffs 4.0) positioned at the proximal region of the affected lower extremity, calibrated to 50% of the individual's lower limb occlusion pressure (LOP). But the pressure system remains deflated throughout active training and resting phases.

  • Sham transcutaneous electrical nerve stimulation (Sham-TENS)Device

    Sham TENS will be delivered to the anterior thigh region of the paretic leg using a 120z Dual-Channel TENS Unit (ITO Physiotherapy \& Rehabilittaion, Co, Ltd, Tokyo, Japan). The TENS stimulation will be at 100 Hz, with 0.2 ms square pulses at an intensity of twice the sensory threshold (defined as the minimum intensity at which subject reported feeling a tingling sensation and below the motor threshold as indicated by the absence of muscle twitching. But the stimulator will only be applied for the first and last 30 seconds.

  • Low-intensity resistance training (LIRT)Behavioural

    The LIRT protocol utilizes 20% of one-repetition maximum (1-RM) as the standardized training load. LIRT including leg extensions, leg presses, and load-bearing squats focused on the affected limb. Each resistance exercise consists of 3 sets of 20 repetitions with rest intervals.

Study groups in NCT06973590
Study groupRoleWhat they receive
LIRT + BFR + TENSExperimentalAll subjects will receive 60-minute sessions of LIRT with both actual BFR and actual TENS intervention, 3 sessions per week for 6 weeks.
Receives: Device: Blood flow restriction (BFR); Device: Transcutaneous electrical nerve stimulation (TENS); Behavioral: Low-intensity resistance training (LIRT)
LIRT + sham BFR + TENSSham comparatorAll subjects will receive 60-minute sessions of LIRT with simulated BFR and actual TENS, 3 sessions per week for 6 weeks.
Receives: Device: Transcutaneous electrical nerve stimulation (TENS); Device: Sham blood flow restriction (Sham-BFR); Behavioral: Low-intensity resistance training (LIRT)
LIRT + BFR + sham TENSSham comparatorAll subjects will receive 60-minute sessions of LIRT with actual BFR and simulated TENS, 3 sessions per week for 6 weeks.
Receives: Device: Blood flow restriction (BFR); Device: Sham transcutaneous electrical nerve stimulation (Sham-TENS); Behavioral: Low-intensity resistance training (LIRT)
LIRT + sham BFR + sham TENSPlacebo comparatorAll subjects will receive 60-minute sessions of LIRT with simulated BFR and simulated TENS, 3 sessions per week for 6 weeks.
Receives: Device: Sham blood flow restriction (Sham-BFR); Device: Sham transcutaneous electrical nerve stimulation (Sham-TENS); Behavioral: Low-intensity resistance training (LIRT)

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Fugl-Meyer Assessment of Lower Extremity (FMA-LE)

    FMA-LE is used to evaluate the lower extremity motor control, including reflexes, voluntary control of isolated movement and coordination. The scale score ranging from 0 to 34, with 17 items and ordinal scoring from 0 to 2. A higher score indicates a better lower extremity motor control.

    Measured: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)

Secondary outcomes (9)
  1. Paretic ankle dorsiflexor/plantarflexor strength

    The paretic ankle dorsiflexor/plantarflexor strength (in kilograms) is measured with a Nicholas hand-held dynamometer (model 01165, Lafayette Instrument Company, Lafayette, IN) in supine lying position. The muscle strength will be measured twice. The average strength of the 2 trials will be recorded. A higher value indicated a better paretic ankle dorsiflexor/plantarflexor strength.

    Measured: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)

  2. Knee extension strength

    Knee extension strength is measured using a Cybex isokinetic dynamometer in isometric mode. Participants will be seated with their back supported and hips flexed at 90°. The axis of rotation of the dynamometer will be aligned with the lateral femoral epicondyle, and the resistance pad will be secured just proximal to the malleoli on the anterior aspect of the leg. The test will be conducted with the knee positioned at 90° of flexion. Following familiarization with the procedure, participants will perform three maximal voluntary isometric contractions, each held for 5 seconds with a 60-second rest period between attempts. The average peak torque value from the three trials will be recorded in Newton-meters (Nm). Higher values indicate greater knee extension strength.

    Measured: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)

  3. 10-Meter Walk Test (10MWT)

    The subject will be asked to walk 10 meter in a comfortable speed. The completion time will be records by stopwatch. The test will be repeated for 2 times. The completion time will be averaged. The shorter the completion time, the better performance is.

    Measured: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)

  4. Timed 'Up and Go' test (TUG)

    The TUG is used to measure the functional mobility. Each subject will be required to rise from a chair with armrests, walk 3 m forward, turn around, return to the chair and sit down. The time taken to complete this task will be measured in seconds with a stopwatch. Each condition will be repeated for 2 times. The completion time will be averaged.

    Measured: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)

  5. Gait Parameters (via GAITRite)

    Gait parameters will be assessed using the GAITRite system (CIR system, Inc., Havertown, Pennsylvania), a pressure-sensitive mat that automatically captures spatiotemporal gait characteristics. Participants will walk at their self-selected comfortable pace along the instrumented walkway.

    Measured: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)

  6. Berg Balance Scale (BBS)

    BBS is a 14-item objective measure that assesses static balance and fall risk in adult patients. Items include tasks such as sitting to standing, standing unsupported, transfers, reaching, turning 360 degrees, and single-leg stance. Each item is scored from 0-4 points (0=unable to perform, 4=independent), with a maximum total score of 56 points. Higher scores indicate better balance.

    Measured: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)

  7. Limits of Stability (LOS) Test

    The Limits of Stability (LOS) test quantifies participants' ability to intentionally shift their center of gravity (COG) to their stability limits without losing balance using Bertec Balance Advantage System (Bertec Corporation, Columbus, OH, USA). Participants stand on a force plate and shift their weight to move a cursor on a screen toward 8 targets arranged in a circular pattern at their theoretical limits of stability (100% LOS). Key parameters measured reaction time (RT) , movement velocity (MVL), directional control (DCL), endpoint excursion (EPE), maximum excursion (MXE). Higher scores indicate better dynamic balance control, except for reaction time where lower scores are better.

    Measured: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)

  8. Weight bearing distribution

    Weight bearing distribution will be assessed using the Bertec Balance Advantage System (Bertec Corporation, Columbus, OH, USA). Participants will stand barefoot on the dual force plate platform with feet positioned at shoulder width and arms resting at their sides. The system's integrated software will measure vertical ground reaction forces under each foot to calculate the percentage of weight distribution between the affected and unaffected lower extremities. Weight bearing measurements will be conducted under four conditions: (1) relaxed standing balance, (2) squat position at 30° knee flexion, (3) squat position at 60° knee flexion, (4) squat position at 90° knee flexion. For each squat position, participants will be instructed to maintain the position for 10 seconds while a handrail will be available for safety but not for weight support.

    Measured: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)

  9. Ultrasound muscle thickness

    Muscle thickness will be evaluated using B-mode ultrasonography with a 5-12 MHz linear-array transducer. Measurements will be performed with participants in a supine position after 10 minutes of rest to allow fluid redistribution. Standard anatomical landmarks will be used to ensure measurement consistency: Rectus Femoris at 50% of the distance between the anterior superior iliac spine and the superior border of the patella; Vastus Lateralis at 2/3 of the distance from the anterior superior iliac spine to the lateral side of the patella; Tibialis Anterior at 30% of the distance from the lateral condyle of the tibia to the lateral malleolus; and Gastrocnemius Medialis at 30% of the distance from the popliteal crease to the lateral malleolus. The transducer will be positioned perpendicular to the muscle surface with minimal pressure to avoid tissue compression. Three consecutive images will be captured for each muscle, and muscle thickness will be measured as the perpendicular distance

    Measured: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted15 May 2025
  2. Study start1 Sep 2024
  3. Primary completion31 Dec 2026 (estimated)
  4. Study completion31 Dec 2026 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Treatment
Allocation
Randomised
Intervention model
Parallel groups
Masking
Single blind
Who is masked
Outcomes assessor
Enrolment
60 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT06973590
Sponsor's protocol ID
2025_BFR+TENS_STROKE
Status last verified
Aug 2026
First submitted
7 May 2025
Last updated
21 Aug 2026
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Questions about this trial

What is this clinical trial studying?

A study testing Blood flow restriction (BFR), Transcutaneous electrical nerve stimulation (TENS) and Low-intensity resistance training (LIRT) in people with Chronic Stroke, run by The Hong Kong Polytechnic University at 1 site in Hong Kong.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 7 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: looking for participants now, as of the sponsor's last update on 21 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Hong Kong. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

Contact Shamay NG, PhD (+852 27664889, shamay.ng@polyu.edu.hk), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Fugl-Meyer Assessment of Lower Extremity (FMA-LE) (time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)). It is what the study was designed to measure, not a finding.

Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 21 Aug 2026.

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