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FibromyalgiaBreath-fibroNCT07404384

Slow Breathing and Resistance Exercise in Fibromyalgia

A study testing Slow Breathing with Visual Pacer and Slow Breathing without Visual Pacer in people with Fibromyalgia and Fibromyalgia Syndrome, run by University of Malaga at 2 sites in Spain.

Enrolling by invitation

Enrolling by invitation. The study team selects and invites participants, usually from an existing group of patients.

Sites and contacts
Official record
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Trial summary

This randomized controlled trial investigates whether slow breathing techniques influence heart rate variability, exercise self-efficacy, and resistance exercise performance in women with fibromyalgia. Read more about this study

Who is it for?
Ages 18 years and older, women only
Conditions the study is for
Fibromyalgia, Fibromyalgia Syndrome
What is being tested?
Slow Breathing with Visual Pacer and Slow Breathing without Visual Pacer
Could I receive a placebo?
No, everyone receives an active treatment
How many people
159 participants
Where
2 sitesSpain
Study dates
Feb 2026to May 2027
Phase
Interventional
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 years and older
  • Women only
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • Female sex
  • Age ≥ 18 years
  • Medical diagnosis of fibromyalgia confirmed by physician
  • Capacity to understand and sign informed consent form
  • Fluency in spoken and written Spanish

Who cannot join

  • Current or past severe mental illness or neurodegenerative disease
  • Current treatment for oncological pathology, degenerative disease, or terminal illness
  • Musculoskeletal injury contraindicating biceps curl exercise
  • Connective tissue disease or arthritis
  • Inability to perform biceps curl exercise due to physical limitations

Trial locations and contacts

2 sites in 1 country. Contact the study team or a site near you to ask about taking part.

Spain2 sites
  • Asociación de Fibromialgia y Síndrome de Fatiga Crónica de Málaga (AFIBROMA)

    Málaga, Málaga, 29010

  • Asociación de Pacientes de Fibromialgia y Síndrome de Fatiga Crónica de Málaga (APAFIMA)

    Málaga, Málaga, 29010

Other trials in Spain

About this study

Official title: Impact of Slow Breathing and Its Interaction With Psychological Variables From the Fear-Avoidance Model of Pain on Heart Rate Variability and Resistance Exercise Performance in Women With Fibromyalgia.

This randomized controlled trial investigates whether slow breathing techniques influence heart rate variability, exercise self-efficacy, and resistance exercise performance in women with fibromyalgia. Participants will be randomly assigned to one of three breathing conditions (slow breathing with visual pacer, slow breathing without pacer, or spontaneous breathing) before performing a biceps curl resistance exercise. The study will examine how breathing patterns interact with psychological variables (anxiety sensitivity, pain catastrophizing, pain hypervigilance, and kinesiophobia) to affect physiological and performance outcomes.

Read the detailed description

Background: Fibromyalgia is considered one of the most representative central sensitivity syndromes, where central sensitization is the predominant characteristic. Resistance and strength training have demonstrated efficacy as therapeutic strategies for fibromyalgia patients. Slow breathing has been shown to reduce anxiety, perceived stress, and pain intensity while increasing heart rate variability (HRV), a biomarker of stress reactivity. The Fear-Avoidance Model of Pain demonstrates that anxiety sensitivity, pain catastrophizing, hypervigilance, and fear of pain/movement largely determine activity levels in chronic pain patients. However, no studies have examined how slow breathing interacts with these psychological variables to enhance resistance exercise performance in fibromyalgia patients.

Study Design: Single-session, three-arm randomized controlled trial with parallel group assignment.

Experimental Procedure:

Phase 1 - Baseline Assessment:

  • Semi-structured interview for demographic and clinical information
  • Administration of self-report questionnaires (detailed below)
  • 5-minute baseline HRV measurement (seated, eyes open, spontaneous breathing)
  • Respiration rate inferred from HRV

Phase 2 - Resistance Exercise Preparation:

  • Determination of optimal weight for biceps curl exercise using submaximal protocol
  • Warm-up: 3 minutes walking + 10 unloaded practice repetitions
  • Progressive weight testing to determine 50% 1-RM equivalent

Phase 3 - Breathing Intervention (8 minutes): Participants randomly assigned to:

  • Condition A: Slow breathing with visual pacer (6 breaths/min: 4-sec inhale, 6-sec exhale) displayed continuously
  • Condition B: Slow breathing without pacer (same pattern, brief training then self-paced)
  • Condition C: Spontaneous breathing at participant's natural rate
  • HRV continuously recorded during all breathing conditions. Respiration rate inferred from HRV.

Phase 4 - Resistance Exercise Test:

  • Biceps curl exercise at 50% estimated 1-RM
  • Maximum repetitions to voluntary exhaustion
  • Proper form maintained (back against wall, arms close to body, full range of motion)

Phase 5 - Post-Exercise Assessment:

  • Immediate measurement of dependent variables (detailed below)
  • 8 min. of rest
  • HRV recording 5 min.

Safety Monitoring: Continuous observation by trained evaluators; clear stopping criteria.

Being tested
Slow Breathing with Visual Pacer, Slow Breathing without Visual Pacer, Spontaneous Breathing (Active Control)
Keywords
Slow Breathing, Diaphragmatic Breathing, Heart Rate Variability, Resistance Exercise, Fear-Avoidance Model, Central Sensitivity Syndrome, Exercise Performance, Pain Catastrophizing, Kinesiophobia
Medical subject headings
Fibromyalgia, Hypoventilation, Kinesiophobia

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Slow Breathing with Visual PacerBehavioural

    Participants receive brief training using a visual pacer displayed on computer screen showing a line that rises during inhalation and falls during exhalation. The pacing is set to 6 respiratory cycles per minute (4 seconds inhalation, 6 seconds exhalation). Participants place one hand below chest and abdomen to monitor diaphragmatic movement. After training, participants continue slow breathing with the visual pacer continuously displayed, maintaining the prescribed respiratory rate.

  • Slow Breathing without Visual PacerBehavioural

    Participants receive identical brief training using the visual pacer to learn the slow breathing pattern (6 cycles per minute: 4 seconds inhalation, 6 seconds exhalation). Hand placement below chest and abdomen to monitor diaphragmatic movement. After training, the visual pacer is removed and participants attempt to maintain the slow breathing pattern independently without external guidance.

  • Spontaneous Breathing (Active Control)Behavioural

    Participants spend equivalent time breathing at their natural, spontaneous rate. They receive similar attention from evaluators but no specific breathing instructions. Participants are instructed to breathe normally at their usual pace and rhythm.

Study groups in NCT07404384
Study groupRoleWhat they receive
Slow Breathing with Visual PacerExperimentalParticipants perform 8 minutes of paced slow breathing (6 breaths/min) with continuous visual guidance before resistance exercise test.
Receives: Behavioral: Slow Breathing with Visual Pacer
Slow Breathing without Visual PacerExperimentalParticipants perform 8 minutes of self-paced slow breathing (6 breaths/min target) after brief training, without continuous visual guidance, before resistance exercise test.
Receives: Behavioral: Slow Breathing without Visual Pacer
Spontaneous BreathingExperimentalParticipants breathe naturally at their spontaneous rate for equivalent duration before resistance exercise test.
Receives: Behavioral: Spontaneous Breathing (Active Control)

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Heart Rate Variability (HRV) - Change from Baseline

    Root mean square of successive differences (RMSSD) in milliseconds

    Measured: Measured: 5 min baseline, 8 min during breathing intervention, and 5 min post-exercise recovery.

  2. Number of Biceps Curl Repetitions

    Number of properly executed biceps curl repetitions at 50% estimated 1-RM performed to voluntary exhaustion with proper form maintained.

    Measured: Immediately during the resistance exercise test (single session).

Secondary outcomes (6)
  1. Exercise-Related Self-Efficacy

    Single-item 0-10 numeric rating scale.

    Measured: Immediately post-exercise.

  2. Fatigue

    Borg Rating Of Perceived Exertion. Rating of perceived exertion is an outcome measure scale used to gauge one's exercise intensity without the need to rely on physiological parameters. The scale rates exertion from a scale of 6 (no exertion) to 20 (maximum effort).

    Measured: Immediately post-exercise

  3. Change in Current Pain Intensity

    Numeric Rating Scale (NRS) 0-10

    Measured: Immediately post-exercise

  4. Change in Anxiety

    Numeric Rating Scale (NRS) 0-10

    Measured: Immediately post-exercise.

  5. Perceived effort required to do the biceps exercise

    Numeric Rating Scale (NRS) 0-10.

    Measured: Immediately post-exercise

  6. Breathing Difficulty

    Numeric Rating Scale (NRS) 0-10

    Measured: Immediately after breathing intervention.

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted11 Feb 2026
  2. Study startFeb 2026 (estimated)
  3. Primary completionApr 2026 (estimated)
  4. Study completionMay 2027 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Basic science
Allocation
Randomised
Intervention model
Parallel groups
Model description
Three-arm parallel group design with 1:1:1 randomization to slow breathing with pacer, slow breathing without pacer, or spontaneous breathing control
Masking
Single blind
Who is masked
Participant
Enrolment
159 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT07404384
Sponsor's protocol ID
UW-UMA_177-2025-H
Acronym
Breath-fibro
Status last verified
Feb 2026
First submitted
4 Feb 2026
Last updated
11 Feb 2026
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
Yes: We will share the joint database through a web link for public access.

Publications

  • Yunus MB. Central sensitivity syndromes: a new paradigm and group nosology for fibromyalgia and overlapping conditions, and the related issue of disease versus illness. Semin Arthritis Rheum. 2008 Jun;37(6):339-52. doi: 10.1016/j.semarthrit.2007.09.003. Epub 2008 Jan 14.

    PubMed 18191990
  • Rogers AH, Farris SG. A meta-analysis of the associations of elements of the fear-avoidance model of chronic pain with negative affect, depression, anxiety, pain-related disability and pain intensity. Eur J Pain. 2022 Sep;26(8):1611-1635. doi: 10.1002/ejp.1994. Epub 2022 Jul 7.

    PubMed 35727200
  • Bamert M, Inauen J. Physiological stress reactivity and recovery: Some laboratory results transfer to daily life. Front Psychol. 2022 Aug 15;13:943065. doi: 10.3389/fpsyg.2022.943065. eCollection 2022.

    PubMed 36046406
  • da Silva JM, de Barros BS, Almeida GJ, O'Neil J, Imoto AM. Dosage of resistance exercises in fibromyalgia: evidence synthesis for a systematic literature review up-date and meta-analysis. Rheumatol Int. 2022 Mar;42(3):413-429. doi: 10.1007/s00296-021-05025-9. Epub 2021 Oct 15.

    PubMed 34652480
  • Goheen J, Anderson JAE, Zhang J, Northoff G. From Lung to Brain: Respiration Modulates Neural and Mental Activity. Neurosci Bull. 2023 Oct;39(10):1577-1590. doi: 10.1007/s12264-023-01070-5. Epub 2023 Jun 7.

    PubMed 37285017
  • Andrade A, de Azevedo Klumb Steffens R, Sieczkowska SM, Peyre Tartaruga LA, Torres Vilarino G. A systematic review of the effects of strength training in patients with fibromyalgia: clinical outcomes and design considerations. Adv Rheumatol. 2018 Oct 22;58(1):36. doi: 10.1186/s42358-018-0033-9.

    PubMed 30657077

Questions about this trial

What is this clinical trial studying?

A study testing Slow Breathing with Visual Pacer and Slow Breathing without Visual Pacer in people with Fibromyalgia and Fibromyalgia Syndrome, run by University of Malaga at 2 sites in Spain.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 5 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: enrolling by invitation, as of the sponsor's last update on 11 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 2 sites in Spain. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Heart Rate Variability (HRV) - Change from Baseline (time frame: Measured: 5 min baseline, 8 min during breathing intervention, and 5 min post-exercise recovery.). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT07404384, which also lists 6 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 11 Feb 2026.

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