WBV Reflex Latency and Mechanical Load

NCT07170709 | Completed

• 2 other identifiers: WBV-BMR-2025-012017.124.IRB2.038
• Study Type: interventional
• Target: 36
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to investigate how the magnitude of mechanical loading affects reflex latency patterns induced by whole-body vibration (WBV). WBV can trigger two types of reflexes: the tonic vibration reflex (TVR) and the bone myoregulation reflex (BMR), which may be influenced by load-bearing condition. The study will include healthy adult volunteers aged 20-50 years. Reflex responses will be recorded from the soleus muscle using surface EMG during both WBV. Different conditions of mechanical loading (i.e., standing on one foot, both feet) and vibration frequencies (30-36 Hz) will be tested. The main outcome will be the latency of the reflex responses, which will help distinguish between TVR and BMR activation. The goal is to better understand how mechanical load modifies reflex response timing and to characterize the underlying afferent pathways. This knowledge may contribute to optimizing vibration-based rehabilitation strategies.

Conditions

Whole-body Vibration; Healthy Volunteers (HV); Muscle Contraction; Postural Balance; Electromyography

Keywords

Whole-Body Vibration; Tonic Vibration Reflex; Bone Myoregulation Reflex; Reflex Latency; Postural Reflexes; Surface Electromyography; Mechanical Loading; Healthy Volunteers; Neuromuscular Physiology

Outcome Measures

Primary Outcomes (1)

• Reflex latency (milliseconds) in the soleus muscle during vibration stimulation

  Reflex latency will be calculated based on surface EMG recordings from the soleus muscle during whole-body vibration at frequencies of 30-36 Hz. Latency will be analyzed using cumulative averaging techniques and expressed in milliseconds.

  Day 1 (single-session, during each experimental condition)

Secondary Outcomes (4)

• EMG amplitude of reflex response in the soleus muscle during vibration stimulation

  Day 1 (single-session, during each experimental condition)

• Reflex type classification (TVR vs BMR) based on latency and mechanical load

  Day 1 (single-session, during each experimental condition)

• Reflex latency variability under different mechanical loading conditions

  Day 1 (single-session, during each experimental condition)

• Effect of vibration frequency on reflex latency and amplitude

  Day 1 (single-session, during each experimental condition)

Study Arms (1)

Whole-Body Vibration in Healthy Volunteers

EXPERIMENTAL

Participants will receive whole-body vibration (WBV) under mechanical loading conditions. Surface EMG recordings from the soleus muscle will be used to evaluate reflex latency at vibration frequencies of 30, 32, 34, and 36 Hz. All interventions will be applied in a single-session experimental design in healthy adult volunteers.

Device: Whole-Body Vibration

Interventions

Whole-Body Vibration DEVICE

Participants will receive whole-body vibration (WBV) at 30-36 Hz under different mechanical loading conditions (e.g., standing on one foot, both feet,). Vibration-induced reflex responses will be recorded from the soleus muscle using surface electromyography. The intervention is designed to evaluate latency differences between tonic vibration reflex (TVR) and bone myoregulation reflex (BMR) under controlled biomechanical scenarios.

Also known as: WBV, Reflex Latency Vibration Protocol

Whole-Body Vibration in Healthy Volunteers

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Aged between 18 and 40 years
• Healthy adult volunteers with no known neurological or musculoskeletal disorders
• Able to provide informed consent
• Willing to comply with the procedures of the study, including EMG and vibration exposure

You may not qualify if:

• History of any neurological condition (e.g., peripheral neuropathy, spinal cord injury, stroke)
• Musculoskeletal injury or surgery involving the lower extremities
• Use of medications affecting neuromuscular function
• Pregnancy
• Presence of implanted electronic devices (e.g., pacemaker)
• Known intolerance to vibration exposure

Sponsors & Collaborators

• Selim Sezikli: lead

Study Sites (1)

Istanbul Physical Medicine and Rehabilitation Training and Research Hospital

Istanbul, Istanbul, 34186, Turkey (Türkiye)

Location

Related Publications (3)

• Karacan I, Turker KS. Exploring neuronal mechanisms of osteosarcopenia in older adults. J Physiol. 2024 Aug 9. doi: 10.1113/JP285666. Online ahead of print.

  PMID: 39119811 BACKGROUND

• Karacan I, Cidem M, Yilmaz G, Sebik O, Cakar HI, Turker KS. Tendon reflex is suppressed during whole-body vibration. J Electromyogr Kinesiol. 2016 Oct;30:191-5. doi: 10.1016/j.jelekin.2016.07.008. Epub 2016 Jul 25.

  PMID: 27485766 BACKGROUND

• Karacan I, Cidem M, Cidem M, Turker KS. Whole-body vibration induces distinct reflex patterns in human soleus muscle. J Electromyogr Kinesiol. 2017 Jun;34:93-101. doi: 10.1016/j.jelekin.2017.04.007. Epub 2017 Apr 24.

  PMID: 28457998 BACKGROUND

Study Officials

• Selim Sezikli, MD

  Istanbul Physical Medicine and Rehabilitation Training and Research Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER GOV
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Principal Investigator / Physical Medicine & Rehabilitation Specialist

Model Details: All participants receive the same sequence of whole-body vibration under different loading conditions. There is no randomization or control group. This is a single-arm, within-subject experimental design evaluating reflex latency under multiple biomechanical scenarios.

Study Record Dates

• First Submitted: August 29, 2025
• First Posted: September 12, 2025
• Study Start: September 2, 2025
• Primary Completion: September 20, 2025
• Study Completion: September 24, 2025
• Last Updated: September 29, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL
• Time Frame: Data will be available beginning 6 months after the primary publication and will remain accessible for 5 years. Access will be granted on a case-by-case basis following review of a research proposal and execution of a formal data-sharing agreement.
• Access Criteria: Access will be limited to qualified researchers who submit a request for a research project that has received prior ethical approval and who agree to comply with the study's confidentiality principles. Data access will be granted through a formal data-sharing agreement executed between the requesting researcher and the study sponsor or relevant institution. The agreement will specify the intended purpose of data use, the duration of access, and the confidentiality obligations. Shared data will consist of de-identified individual participant data (IPD), with all potentially identifying information removed. Supporting documents such as the study protocol, statistical analysis plan, and analytic code will also be provided to promote research transparency.

Locations

TU (1)