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Heart Rate Variability Biofeedback in Security Forces

Heart Rate Variability Biofeedback in Distress Regulation and Burnout Prevention Among Security Forces

Status
Recruiting
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07386951
Acronym
GNR-HRVB
Enrollment
50
Registered
2026-02-04
Start date
2026-01-28
Completion date
2026-08-01
Last updated
2026-02-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Burnout, Psychological Distress, Well-Being, Psychological

Keywords

Heart rate variability biofeedback, HRV biofeedback, Burnout, Stress management, Psychological distress, Mental health promotion, Workplace well-being

Brief summary

This exploratory study evaluates the effectiveness of a 12-session Heart Rate Variability Biofeedback (HRV-BFB) protocol in reducing distress and burnout while promoting psychological well-being among Portuguese National Republican Guard (GNR) professionals. Exposed to high occupational stress from unpredictable risks, shift work, and limited resources, these individuals face elevated vulnerability to chronic stress outcomes. The intervention leverages real-time HRV feedback to enhance autonomic regulation, breathing techniques, and emotional self-regulation.

Detailed description

Security forces like the GNR play a critical role in public safety but endure chronic stress from violence exposure, rapid decisions, shift rotations, and institutional resource shortages, heightening risks of distress, burnout, and impaired well-being. Distress arises when perceived threats exceed coping resources, leading to persistent negative emotions and health disruptions. Burnout manifests as exhaustion, mental distancing, and reduced efficacy from unmanaged chronic stress, with organizational impacts including absenteeism and eroded public trust. Psychological well-being encompasses multidimensional aspects like autonomy, relationships, and purpose beyond mere absence of illness. Traditional interventions face barriers such as stigma and access issues in rural GNR contexts, necessitating flexible, self-administered tools. Intervention: HRV-BFB Protocol HRV-BFB trains participants to consciously modulate physiological responses via real-time monitoring of heart rate variability (HRV), reflecting sympathetic-parasympathetic balance. Low HRV links to mental health risks, while training targets resonance frequency breathing (\ 6 breaths/min or 0.1 Hz) to boost HRV amplitude, cardiac coherence, and baroreflex strength. Delivered autonomously via app post-initial guidance, the 12-session protocol requires no daily clinician oversight, enhancing accessibility for dispersed GNR personnel. Evidence shows HRV-BFB reduces stress, anxiety, depression, and burnout while fostering well-being in high-stress groups like emergency workers. Study Objectives This exploratory trial tests whether HRV-BFB significantly lowers distress (multidimensional: physical, cognitive, emotional, behavioral), burnout levels, and boosts psychological well-being in GNR professionals. It aims to inform scalable interventions tailored to Portuguese police realities, addressing gaps in institutional support.

Interventions

BEHAVIORALHeart Rate Variability Biofeedback (HRV-BFB) Training

Participants receive a structured heart rate variability biofeedback (HRV-BFB) training protocol delivered over 4 weeks. The intervention uses a portable chest-worn ECG sensor (eSense Pulse) connected via Bluetooth to a mobile application that provides real-time visual feedback of heart rate variability. Each participant completes 12 individual sessions of 12 minutes each (one session every 2 days). Sessions take place in a quiet room and follow a standardized format: a brief preparation phase, followed by approximately 10 minutes of guided breathing at resonance frequency (around 6 breaths per minute) using a visual breathing guide. The application displays color-coded feedback indicating how closely the participant's physiological response matches the target HRV pattern, and participants are instructed to adjust their breathing and recall positive memories to maximize time in the desired state. The aim is to increase HRV, strengthen parasympathetic activation, and improve stress and

Sponsors

Egas Moniz - Cooperativa de Ensino Superior, CRL
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE

Masking description

Due to the nature of the intervention, participants and investigators are aware of who receive HRV biofeedback training or not.

Intervention model description

A randomized, parallel-group clinical trial in which participants are allocated to either a 4-week heart rate variability biofeedback (HRV-BFB) training program or to a no-intervention control condition, with assessments at baseline, post-intervention (4 weeks), and 10-week follow-up.

Eligibility

Sex/Gender
ALL
Age
18 Years to 55 Years
Healthy volunteers
Yes

Inclusion criteria

1. Operational military personnel of the Guarda Nacional Republicana (GNR) performing security, patrol, criminal investigation, or road safety duties 2. Any military rank or professional category within operational roles 3. Age between 18 and 55 years, inclusive 4. Both males and females 5. Capable of providing informed consent in Portuguese language

Exclusion criteria

1. Extended sick leave or medical absence 2. Currently involved in serious disciplinary proceedings 3. Use, modification, or initiation of psychotropic medication (including antidepressants, anti-anxiety medications, antipsychotics, mood stabilizers) within the past 6 months

Design outcomes

Primary

MeasureTime frameDescription
Change in Psychological Distress (Kessler Psychological Distress Scale - K10)Baseline (Week 0), Post-intervention (Week 4), Follow-up (Week 10)The Kessler Psychological Distress Scale (K-10) is a 10-item self-report measure assessing psychological distress over the past 30 days. Items measure anxiety and depressive symptoms on a 5-point Likert scale (1=never to 5=always). Total score range: 10-50 (higher scores indicate greater distress). Portuguese validation: α=0.91. Primary outcome is change from baseline to post-intervention (week 4) and follow-up (week 10).
Change in Occupational Burnout (Burnout Assessment Tool - BAT-12)Baseline (Week 0), Post-intervention (Week 4), Follow-up (Week 10)The Burnout Assessment Tool Short Form (BAT-12) is a 12-item self-report measure of occupational burnout across 4 dimensions: exhaustion (3 items), mental distance (3 items), cognitive impairment (3 items), emotional impairment (3 items). 5-point Likert scale (1=never to 5=always). Total score range: 12-60. Portuguese validation: α=0.85. Primary outcome is change from baseline to post-intervention and follow-up.
Change in Psychological Well-Being (WHO-5 Well-Being Index)Baseline (Week 0), Post-intervention (Week 4), Follow-up (Week 10)The WHO-5 Well-Being Index is a 5-item self-report measure of psychological well-being over the past 2 weeks. Items assess positive mood, vitality, sleep, daily functioning, and life satisfaction on a 0-5 scale. Total score range: 0-25 (higher=higher well-being). Primary outcome is change from baseline to post-intervention and follow-up.

Secondary

MeasureTime frameDescription
SDNN (Standard Deviation of NN Intervals) - Heart Rate VariabilityBaseline (Week 0), after each of 12 training sessionsSDNN measures the standard deviation of the average NN (R-R) intervals in milliseconds during a recording period. It is a general indicator of overall heart rate variability and reflects the body's overall capacity for physiological adaptation and autonomic flexibility. Higher SDNN values indicate better autonomic regulation.
RMSSD (Root Mean Square of Successive Differences) - Parasympathetic ActivityBaseline (Week 0), after each of 12 training sessionsRMSSD measures the root mean square of successive differences between adjacent NN (R-R) intervals in milliseconds. It is a primary time-domain measure of high-frequency heart rate variability and specifically reflects parasympathetic (vagal) nervous system activity and the body's recovery capacity. Higher RMSSD indicates stronger parasympathetic tone.
Stress Index - Autonomic Balance IndicatorBaseline (Week 0), after each of 12 training sessionsThe Stress Index is a proprietary metric derived from heart rate variability analysis that quantifies autonomic nervous system balance. Lower values indicate better autonomic regulation and lower physiological stress levels. Higher values reflect sympathetic dominance and poorer stress adaptation.

Countries

Portugal

Contacts

CONTACTPaulo Chaló, PhD
pchalo@egasmoniz.edu.pt(+351) 212 946 700

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 7, 2026