This clinical trial investigates the effects of blood flow restriction (BFR) combined with instability resistance training (IRT) on balance, mobility, and motor function in patients with Parkinson's disease (PD). The study aims to determine whether low-intensity resistance exercises with BFR are well-tolerated and effective for improving muscle strength, balance, and physical function in individuals with PD.
Blood flow restriction training involves applying a pneumatic cuff to the proximal thighs during exercise, partially restricting arterial inflow while completely occluding venous outflow. This technique allows for muscle strength gains at significantly lower loads (20-30% of 1RM) compared to traditional resistance training, making it particularly suitable for patients who cannot tolerate high-intensity exercise.
| Parameter | Value |
|---|---|
| NCT Number | NCT06508801 |
| Status | Recruiting |
| Phase | Not Applicable (Feasibility) |
| Sponsor | The University of Texas Health Science Center at San Antonio |
| Principal Investigator | Anjali Sivaramakrishnan, PhD, PT |
| Collaborators | National Institute on Aging (NIA) |
| Intervention | Blood Flow Restriction + Instability Resistance Training |
| Enrollment | 20 participants (estimated) |
| Start Date | January 7, 2025 |
| Primary Completion | December 2026 |
| Completion Date | December 2026 |
| Location | San Antonio, Texas, United States |
Parkinson's disease is a progressive neurodegenerative disorder affecting the dopaminergic neurons in the substantia nigra pars compacta. Motor symptoms include tremor, rigidity, bradykinesia, and postural instability. Postural instability is particularly disabling as it leads to falls, reduced mobility, and decreased quality of life.
Traditional high-intensity resistance training can be challenging for PD patients due to:
Blood flow restriction training offers a solution by:
BFR plus IRT Group:
IRT Only Control Group:
The trial utilizes progressive instability devices:
Progression occurs as participants demonstrate reduced body sway on each device.
Blood flow restriction works through several mechanisms:
Metabolic Stress: Partial occlusion creates a hypoxic environment that accumulates metabolites (lactate, inorganic phosphate) in the muscle, stimulating muscle growth pathways.
Hormonal Response: BFR exercise increases secretion of growth hormone and IGF-1, promoting muscle protein synthesis.
Muscle Fiber Recruitment: The technique preferentially activates fast-twitch (Type II) muscle fibers, which are critical for strength but typically require high loads to engage.
Cellular swelling: The accumulation of metabolites and fluid within muscle cells activates anabolic signaling pathways.
Autoregulation: BFR may improve proprioception and neuromuscular control, potentially benefiting balance in PD patients.
Instability resistance training targets:
| Measure | Description |
|---|---|
| Feasibility Metric | Dropout and adverse event rate <20% (acceptable if ≤2/10 participants) |
| Measure | Timepoint | Description |
|---|---|---|
| miniBESTest | Baseline to 14 weeks | Balance evaluation (0-28 points, 14 items scored 0-2) |
| 30-second Chair Stand | Baseline to 14 weeks | Functional mobility - stands from sitting in 30 seconds |
| MDS-UPDRS Part III | Baseline to 14 weeks | Motor severity (0-72 points, 18 items) |
| Postural Sway (BioSway) | Baseline to 14 weeks | Postural stability on Biodex BioSway |
| Spinal Excitability | Baseline to 14 weeks | H-reflex recruitment curves |
| Hip Abductor Strength | Baseline to 14 weeks | Isokinetic dynamometry |
| Knee Extensor Strength | Baseline to 14 weeks | Isokinetic dynamometry |
| Ankle Plantar Flexor Strength | Baseline to 14 weeks | Isokinetic dynamometry |
| PDQ-39 | Baseline to 14 weeks | Quality of life (0-100, lower = better) |
Postural instability in PD results from:
The combination of BFR and instability training may address multiple aspects:
The trial includes peripheral nerve stimulation to measure spinal excitability via H-reflex. This addresses whether BFR affects the monosynaptic reflex arc, which is relevant because: