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

Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age50-80
SponsorThe Hong Kong Polytechnic University

About this trial

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.

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.

Eligibility criteria

Qualifiers

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;

Disqualifiers

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;

Trial design

Treatments tested in this trial

  • 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)

Treatment groups

80 Participants
are divided into 4 treatment groups