Electromyographic Response to Blood Flow Restriction Exercise in Healthy Adults

Electromyographic Analysis of Immediate Neuromuscular Response After Low-Load Knee Extension Exercise With and Without Blood Flow Restriction in Healthy Adults

This study evaluated the immediate neuromuscular response to low-load knee extension exercise performed with and without blood flow restriction in healthy young adults.

Blood flow restriction is a training method in which a pressure cuff is applied to the upper part of a limb to partially reduce blood flow during exercise. In this study, each participant completed the same knee extension exercise protocol under two conditions: with blood flow restriction and without blood flow restriction. The blood flow restriction pressure was individualized according to each participant's arterial occlusion pressure.

Surface electromyography was used to record the activity of the vastus lateralis muscle during the exercise protocol. Muscle activation was mainly assessed using the root mean square amplitude normalized to a maximal voluntary isometric contraction measured before exercise. Maximal voluntary isometric contraction was also recorded before and after the protocol to explore immediate changes in maximal muscle activation.

The study was conducted in healthy adults and aimed to compare the electromyographic response between the blood flow restriction and non-restriction conditions during a standardized low-load exercise task.

Study Overview

• Status: Completed
• Conditions: Electromyographic Response to Blood Flow Restriction Exercise in Healthy Adults
• Intervention / Treatment: Other: Low-load knee extension exercise with blood flow restriction; Other: Low-load knee extension exercise without blood flow restriction

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

Contacts and Locations

Study Locations

• Spain
  • Badajoz
    • Badajoz, Badajoz, Spain, 06006
      • University of Extremadura

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

Age 18 years or older. Healthy adults. Absence of active pain or musculoskeletal injury in the lower limbs at the time of assessment.

Ability to understand the study procedures. Voluntary agreement to participate and provision of written informed consent.

Exclusion Criteria:

History of neuromuscular disease. History of cardiovascular disease. History of peripheral vascular disease. History of thromboembolic events. Uncontrolled hypertension. Skin lesions or skin conditions preventing placement of the blood flow restriction cuff or surface electromyography electrodes.

Recent lower limb surgery. Pregnancy. Any other contraindication to blood flow restriction exercise.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Low-load knee extension exercise with blood flow restriction; Participants performed a low-load knee extension exercise protocol with blood flow restriction applied to the proximal thigh. The blood flow restriction pressure was individualized and set at 80% of the participant's arterial occlusion pressure. Surface electromyography of the vastus lateralis was recorded throughout the exercise protocol.	Other: Low-load knee extension exercise with blood flow restriction; Participants completed a low-load knee extension exercise protocol consisting of 75 repetitions distributed across four sets: 30, 15, 15, and 15 repetitions. During this condition, a pressure cuff was placed on the proximal thigh and inflated to 80% of the participant's individualized arterial occlusion pressure. Surface electromyography of the vastus lateralis was recorded continuously during the protocol.
Active Comparator: Low-load knee extension exercise without blood flow restriction; Participants performed the same low-load knee extension exercise protocol without blood flow restriction. Surface electromyography of the vastus lateralis was recorded throughout the exercise protocol.	Other: Low-load knee extension exercise without blood flow restriction; Participants completed the same low-load knee extension exercise protocol consisting of 75 repetitions distributed across four sets: 30, 15, 15, and 15 repetitions, without application of blood flow restriction. Surface electromyography of the vastus lateralis was recorded continuously during the protocol.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Vastus Lateralis Electromyographic Amplitude Normalized to Maximal Voluntary Isometric Contraction	Surface electromyographic activity of the vastus lateralis was assessed during the low-load knee extension exercise protocol. The root mean square amplitude was normalized to the maximal voluntary isometric contraction recorded before exercise and expressed as percentage of maximal voluntary isometric contraction (%MVIC). Measurements were extracted at predefined time points across the four exercise sets in both experimental conditions.	During the exercise protocol, within a single experimental session.

Collaborators and Investigators

• Sponsor: Universidad de Extremadura

Study record dates

Study Major Dates

• Study Start (Actual): February 1, 2026
• Primary Completion (Actual): April 15, 2026
• Study Completion (Actual): April 15, 2026

Study Registration Dates

• First Submitted: June 12, 2026
• First Submitted That Met QC Criteria: June 12, 2026
• First Posted (Actual): June 17, 2026

Study Record Updates

• Last Update Posted (Actual): June 17, 2026
• Last Update Submitted That Met QC Criteria: June 12, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: 13

Drug and device information, study documents

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