taVNS During Exercise and Recovery in Chronic Spinal Cord Injury

NCT07524491 | Completed

• 2 other identifiers: UIB-taVNS-SCI-202419CER24
• Study Type: interventional
• Target: 35
• Locations: 1 country
• Sites: 1

Brief Summary

This study investigates the effects of transcutaneous auricular vagus nerve stimulation (taVNS) on autonomic cardiovascular regulation during exercise and recovery in individuals with chronic spinal cord injury (SCI). Participants undergo two experimental conditions (active taVNS and sham stimulation) in a randomized crossover design while performing a standardized exercise protocol. Heart rate variability (HRV) is used as a non-invasive biomarker to assess autonomic nervous system dynamics across different phases (baseline, exercise, and recovery). The aim is to characterize physiological responses to neuromodulation and explore whether taVNS modulates autonomic adaptability in this population. This is a mechanistic physiological study designed to improve the understanding of autonomic regulation in SCI and to explore potential biomarkers of response to neuromodulation.

Conditions

Spinal Cord Injury, Chronic

Keywords

Transcutaneous auricular vagus nerve stimulation; Heart rate variability; Autonomic nervous system; Neuromodulation; Spinal cord injury; Exercise physiology; Nonlinear dynamics

Outcome Measures

Primary Outcomes (1)

• DFA α2

  Detrended fluctuation analysis (α2) derived from RR intervals to assess long-term fractal scaling properties of heart rate variability. RR intervals are recorded continuously and analyzed offline. Data are processed using 5-minute overlapping windows. The value reported at each specific time point represents the calculation for the preceding 5-minute window to characterize autonomic regulation across the session.

  Baseline (last 5 minutes of rest), 10, 15, 20, 25, 30, 35, and 40 minutes.

Secondary Outcomes (4)

• RMSSD (ms)

  Baseline (last 5 minutes of rest), 10, 15, 20, 25, 30, 35, and 40 minutes.

• HF power (ms²)

  Baseline (last 5 minutes of rest), 10, 15, 20, 25, 30, 35, and 40 minutes.

• LF power (ms²)

  Baseline (last 5 minutes of rest), 10, 15, 20, 25, 30, 35, and 40 minutes.

• SD1 (ms)

  Baseline (last 5 minutes of rest), 10, 15, 20, 25, 30, 35, and 40 minutes.

Study Arms (2)

Active taVNS

EXPERIMENTAL

Transcutaneous auricular vagus nerve stimulation applied during the experimental protocol.

Device: Transcutaneous Auricular Vagus Nerve Stimulation

Sham Stimulation

SHAM COMPARATOR

Sham stimulation applied under identical experimental conditions without effective vagus nerve activation.

Device: Sham Stimulation

Interventions

Transcutaneous Auricular Vagus Nerve Stimulation DEVICE

Non-invasive electrical stimulation applied to the auricular branch of the vagus nerve using transcutaneous electrodes during the experimental protocol.

Active taVNS

Sham Stimulation DEVICE

Sham stimulation delivered with identical device setup but without effective activation of the vagus nerve.

Sham Stimulation

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults (≥18 years) with chronic spinal cord injury
• Medically stable condition
• Ability to perform the exercise protocol
• Ability to provide informed consent

You may not qualify if:

• Acute spinal cord injury
• Severe cardiovascular or respiratory instability
• Use of medications significantly affecting autonomic function
• Skin lesions or contraindications to transcutaneous stimulation
• Cognitive impairment preventing protocol compliance

Sponsors & Collaborators

• University of the Balearic Islands: lead
• University of the Balearic Islands - Institute for Health Sciences Research (UNICS): collaborator
• Health Research Institute of the Balearic Islands (IdISBa, Spain): collaborator

Study Sites (1)

University of the Balearic Islands

Palma de Mallorca, Balearic Islands, 07122, Spain

Location

MeSH Terms

Conditions

Spinal Cord Injuries; Bronchiolitis Obliterans Syndrome

Condition Hierarchy (Ancestors)

Spinal Cord Diseases; Central Nervous System Diseases; Nervous System Diseases; Trauma, Nervous System; Wounds and Injuries; Organizing Pneumonia; Bronchiolitis Obliterans; Bronchiolitis; Bronchitis; Bronchial Diseases; Respiratory Tract Diseases; Lung Diseases, Obstructive; Lung Diseases; Graft vs Host Disease; Immune System Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: Participants are blinded to the stimulation condition (active taVNS vs sham), while investigators are aware of the assigned condition.
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Researcher

Model Details: Randomized, controlled, crossover experimental study with two conditions (active taVNS and sham). Each participant undergoes both conditions during standardized exercise and recovery phases.

Study Record Dates

• First Submitted: March 17, 2026
• First Posted: April 13, 2026
• Study Start: October 31, 2024
• Primary Completion: October 31, 2024
• Study Completion: October 31, 2024
• Last Updated: April 13, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

ES (1)