The Acute Effects of Blood Flow Restriction on Ankle Muscle Reaction Time and Proprioception in Healthy Individuals

his randomized controlled crossover study aims to investigate the acute effects of lower limb blood flow restriction (BFR) on ankle joint proprioception, postural control, and muscle activation in healthy adults. Each participant will complete test sessions under BFR (60% individualized arterial occlusion pressure) and control (20 mmHg sham) conditions. Outcome measures include joint position sense, kinesthesia, static and dynamic balance performance, and electromyographic (EMG) activity and reaction times of selected lower limb tibialis anterior and peroneus longus muscles.

Study Overview

• Status: Active, not recruiting
• Conditions: Blood Flow Restriction; Ankle Proprioception
• Intervention / Treatment: Other: Blood Flow Restriction; Other: Sham Blood Flow Restriction

Detailed Description

Lateral ankle sprains are among the most common musculoskeletal injuries and may lead to chronic ankle instability (CAI), partly due to impaired proprioception and neuromuscular control. Blood flow restriction (BFR) training is widely used to augment muscular adaptations with low external loads; however, its acute effects on joint proprioception and sensorimotor control, particularly at the ankle joint, remain unclear and may be detrimental under certain conditions. This randomized controlled crossover trial will examine the effects of a single-session lower limb BFR application on ankle joint position sense, kinesthesia, static and dynamic balance, and EMG-based reaction time and activity of lower limb muscles in healthy adults. Participants aged 18-40 years without recent ankle sprain, neuromuscular, cardiovascular, or thromboembolic disease will undergo standardized proprioception tests using an isokinetic dynamometer, static balance tests on a force platform, Y-balance test, and inversion simulation platform assessments under BFR (60% arterial occlusion pressure) and low-pressure control (20 mmHg) conditions. Individual arterial occlusion pressure (AOP) will be determined using Doppler ultrasound, and BFR will be applied with a pneumatic cuff at the most proximal thigh. All measurements will be performed on the dominant lower limb with sessions scheduled at the same time of day to minimize circadian variability. The primary hypothesis is that acute lower limb BFR will worsen ankle joint proprioception and sensorimotor control compared with the control condition, potentially indicating a transient increase in injury risk during BFR-assisted activities.

• Study Type: Interventional
• Enrollment (Estimated): 24
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Bursa, Turkey (Türkiye), 16059
    • Uludag University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Aged between 18 and 40 years
• No known neuromuscular or cardiovascular disease

Exclusion Criteria:

• History or presence of cardiac, coronary artery, or peripheral arterial disease
• Presence or history of varicose veins, hypertension, diabetes mellitus, or pulmonary disease
• History of pulmonary embolism or deep vein thrombosis
• Use of medications affecting the central nervous or cardiovascular systems
• Use of oral contraceptives or anticoagulants
• Pregnancy
• Open wounds or significant scar tissue at the cuff application site
• History of lower extremity musculoskeletal injury or surgery
• Any neurological, vascular, or systemic condition that may interfere with test performance

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Blood Flow Restriction; Participants perform balance/proprioception tests under lower limb blood flow restriction at % 60 AOP.	Other: Blood Flow Restriction; Arm Description: Participants perform balance/proprioception tests under lower limb blood flow restriction at % 60 AOP.
Sham Comparator: Sham BFR; Sham BFR Description: Participants perform the same tests with sham(20 mmHg) blood flow restriction	Other: Sham Blood Flow Restriction; Sham BFR Description: Participants perform the same tests with sham(20 mmHg) blood flow restriction

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Ankle Joint Position Sense Error (degrees)	Absolute error (degrees) between target and reproduced angles during passive and active joint position sense tests in inversion and plantar flexion, measured with an isokinetic dynamometer.	day 1 and day 2
Static Balance Performance	Center of pressure path length (mm) in single-leg and tandem stance with eyes open/closed on force platform (HUR SmartBalance).	day 3
Change in Kinesthesia Threshold (degrees)	Minimal angular displacement (degrees) at which movement is first perceived in inversion and plantarflexion.	day 1 and day 2
Static balance performance	sway velocity (mm/s) in single-leg and tandem stance with eyes open/closed on force platform (HUR SmartBalance).	day 3
static balance performance	sway area (mm^2) in single-leg and tandem stance with eyes open/closed on force platform (HUR SmartBalance).	day 3

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Y-Balance Test Reach Distances (cm)	Anterior, posteromedial and posterolateral reach distances of the tested limb.	day 4
Peroneus Longus and Tibialis Anterior Reaction Time (ms)	Time from onset of platform-induced inversion to EMG activation exceeding 2× resting activity.	day 4
Lower Limb EMG Activity (%MVIC)	Mean EMG amplitude normalized to maximal voluntary isometric contraction values.	day 4

Collaborators and Investigators

• Sponsor: Uludag University
• Investigators: Study Director: ufuk sekir, Department of Sports Medicine, Bursa Uludağ University

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2025
• Primary Completion (Estimated): December 30, 2025
• Study Completion (Estimated): January 10, 2026

Study Registration Dates

• First Submitted: November 14, 2025
• First Submitted That Met QC Criteria: December 14, 2025
• First Posted (Actual): December 29, 2025

Study Record Updates

• Last Update Posted (Actual): December 29, 2025
• Last Update Submitted That Met QC Criteria: December 14, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: ankle; proprioception; blood flow restriction
• Additional Relevant MeSH Terms: Therapeutics; Physical Therapy Modalities; Patient Care; Exercise Therapy; Rehabilitation; Aftercare; Continuity of Patient Care; Blood Flow Restriction Therapy
• Other Study ID Numbers: 2025-15/31

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No