Influence of Manual and Electrical Vagal Stimulation on Autonomic Activity and Other Dysautonomous Symptoms in a Healthy Population.

Summary

The objective of this clinical, longitudinal, prospective, randomised (randomised) unmasked study is to analyse whether electrical and manual vagal stimulation produces changes in heart rate variability in a healthy population and it have a beneficial clinical effect in reducing dysautonomic symptoms.

The main questions it seeks to answer are:

* Will non-invasive (manual and electrical) stimulation of the vagus nerve produce a significant change in heart rate variability, generating effects on the regulation of the autonomic nervous system, increasing the activation of the parasympathetic nervous system and decreasing the activation of the sympathetic nervous system?
* Will non-invasive (manual and electrical) stimulation of the vagus nerve have a beneficial clinical effect in reducing dysautonomic symptoms such as fatigue and improving sleep quality?
* Will noninvasive (manual and electrical) vagus nerve stimulation improve quality of life?
* Are there differences in the level of satisfaction with the treatment after the intervention program received?

Two groups of participants will be formed:

* Transcutaneous auricular vagus nerve stimulation consists of applying electrical stimulation to the auricular branch of the vagus nerve using a 2-pole stimulation electrode. Stimulation is performed for 1 hour per day for 10 days (5 days per week).
* Manual vagus nerve intervention consists of applying a protocol of manual therapy techniques to the vagus nerve and along its path, during 4 sessions lasting 30 minutes, 2 interventions per week.

Conditions

• Healthy

Interventions

DEVICE

Electrical stimulation of the vagus nerve

The intervention consists of applying transcutaneous electrical stimulation to the auricular branch of the vagus nerve using a bipolar stimulation electrode. A commercially available transcutaneous electrical stimulation device approved for human use will be used (tVNS R (Hook), from tVNS® Technologies GmbH, Erlangen, Germany). The electrode will be placed on the left ear in contact with the cimba turbinate, an area innervated by the auricular branch of the left vagus nerve. Stimulation protocol: Stimulation will be administered in 60-minute/day cycles for 10 days (5 days a week). Stimulation parameters are: Pulse width: 500 μs, Frequency: 25 Hz, Alternating duty cycle: 60 seconds ON followed by 10 seconds OFF, Total time: 60 minutes per day. Current intensity: 200% of the perception threshold, as long as it is tolerated and does not cause pain.

PROCEDURE

Manual stimulation of vagus nerve

The intervention consists of applying a protocol of manual therapy techniques to the vagus nerve and its pathway, during four 30-minute sessions, two interventions per week for two consecutive weeks. The therapeutic protocol is structured around a total of nine specific maneuvers. The intervention will begin with the application of three techniques targeting the cervical region, followed by two maneuvers focused on the anterior region of the neck. Two techniques will then be performed on the thorax, and finally, two mobilizations targeting the abdominal region.

Sponsors & Collaborators

• Escoles Universitaries Gimbernat

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

40 Years

Max Age

70 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2026-07-31

Primary Completion

2026-09-30

Completion

2026-10-31