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NCT Number: NCT07455968

Free Diving Breathing Training in Allergic Rhinitis

The purpose of this study was to investigate the effects of diver-style breathing training on symptoms, pulmonary function, and respiratory muscle, in patients with allergic rhinitis.

Active, Not Recruiting

This study is active but is not currently recruiting participants.

Key information

Age range

18 year–35 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Faculty of Sports Science, Chulalongkorn University

Bangkok, 10330, Thailand

About this study

This study aims to investigate the effects of diver-style breathing training in patients with allergic rhinitis. A total of 30 patients aged 18-35 years were recruited from students and staff of Chulalongkorn University, as well as patients attending the Chulalongkorn University Health Service Center and King Chulalongkorn Memorial Hospital. Participants were randomly assigned into two groups: an experimental group (n = 15) that received diver-style breathing training and a control group (n = 15) that continued their usual daily activities without any exercise intervention.

The independent variable was diver-style breathing training. The dependent variables included rhinitis symptom outcomes (symptom scores, Peak Nasal Inspiratory Flow, nasal blood flow, and Fractional Exhaled Nitric Oxide), pulmonary function parameters (FVC, FEV1, FEV1/FVC, FEF25-75%, MVV, and breath-holding time), and respiratory muscle strength (MIP and MEP).

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Patients diagnosed with persistent allergic rhinitis (allergen of any type), both male and female, presenting with nasal congestion, sneezing, nasal itching, and rhinorrhea occurring more than 4 days per week, with an average symptom score greater than 7. Eligibility was determined using the Rhinitis Symptoms Score (0, 1, 2, and ≥3 scale) assessed over the previous week and on the day of testing. Participants must not have any complications such as sinusitis, Eustachian tube dysfunction, or asthma.
  • No history of other respiratory diseases, including bronchitis, pertussis, pneumonia, pneumonitis, pulmonary aspergilloma, tuberculosis, asthma, lung cancer, emphysema, or other related conditions.
  • No regular exercise training exceeding 20 minutes per session, 3 days per week or more, during the 6 months prior to participation.
  • No regular consumption of vitamin supplements or herbal products at least 3 days per week during the 6 months prior to participation.
  • Ability to discontinue the following medications before and during the study period: Antihistamines for at least 3 days, Oral steroids and nasal steroids for at least 2 weeks, Leukotriene receptor antagonists for at least 1 week
  • Participants were permitted to use decongestants (pseudoephedrine) if necessary. All participants were advised to consult their primary physician before discontinuing any medication and to ensure that their physical condition was appropriate for participation in the breathing training program.
  • Willingness to participate voluntarily and provide written informed consent.

Exclusion criteria

  • Inability to continue participation due to unforeseen circumstances, such as injury or illness.
  • Absence from more than 8 training sessions out of a total of 40 sessions.
  • Withdrawal of consent or unwillingness to continue participation.
  • Inability to discontinue medications according to the specified criteria.
  • Exacerbation of allergic rhinitis symptoms that prevents continued participation, such as persistent rhinorrhea or severe nasal congestion causing difficulty breathing.

Treatment and study plan

Free diving breathing training

Other

The diver-style breathing training program lasts 40 minutes per session. Participants sit upright with proper posture and begin with 5 minutes of normal breathing. They then perform a progressive deep inhalation technique: inhaling through the nose to expand the abdomen, continuing to expand the chest, and finally inhaling further until a sensation of throat tightness is felt. The breath is then held for at least 20 seconds or as long as possible before exhaling through the mouth. Each cycle counts as one round, and participants aim to gradually increase their breath-holding duration over 30 minutes. The session ends with 5 minutes of normal breathing.

Primary outcomes

  1. Rhinitis symptom scores

    Time frame: Change from Baseline Rhinitis symptom scores at 8 weeks.

    Nasal symptoms were assessed using Total Nasal Symptom Score (TNSS) questionnaire. The subjects were asked to score symptoms of persistent allergic rhinitis before and after yoga training protocol. The total nasal symptom scores were computed as the sum of four individual nasal symptom scores; nasal congestion, itching, sneezing, and rhinorrhea. The scores ranged from 0 to 3 scale (0=none, 1=mild, 2=moderate, 3= severe)

  2. Peak nasal inspiratory flow; PNIF

    Time frame: Change from Baseline respiratory muscle strength at 8 weeks.

    Participants were instructed to inhale through the device as quickly and forcefully as possible using a Peak Nasal Inspiratory Flow (PNIF) meter.

  3. Nasal blood flow

    Time frame: Change from Baseline Rhinitis symptom scores at 8 weeks.

    Laser Doppler flowmetry (DRT4, Moor Instruments, UK) was used to measure the NBF. Before the test, each subject rested for 1 hour in a separate room. During the test, the participants were instructed to breathe normally and not to speak, cough, or move. A lateral endoscopic probe with a flexible 1.34-mm-diameter flexible nylon sheath was placed on the front of the nose.

  4. Fractional Exhaled Nitric Oxide Testing; FeNO

    Time frame: Change from Baseline Rhinitis symptom scores at 8 weeks.

    FeNO Monitor (BedFont, UK) was used to measure the FeNO. The participants inhaled deeply for 2 to 3 seconds before exhaling slowly, which normally took 10 seconds.

Secondary outcomes

  1. Forced Vital Capacity; FVC

    Time frame: Change from Baseline respiratory muscle strength at 8 weeks.

    Participants were seated in a chair and wore a nasal clip during the assessment. They first performed three cycles of slow, normal breathing, followed by a demonstration of forced inspiration and expiration, and then returned to normal breathing.

  2. Forced Expiratory Volume in one second; FEV1

    Time frame: Change from Baseline respiratory muscle strength at 8 weeks.

    Participants were seated in a chair and wore a nasal clip during the assessment. They first performed three cycles of slow, normal breathing, followed by a demonstration of forced inspiration and expiration, and then returned to normal breathing.

  3. Forced Expiratory Flow at 25-75% of FVC; FEF25 - 75 %

    Time frame: Change from Baseline respiratory muscle strength at 8 weeks.

    Participants were seated in a chair and wore a nasal clip during the assessment. They first performed three cycles of slow, normal breathing, followed by a demonstration of forced inspiration and expiration, and then returned to normal breathing.

  4. Maximum Voluntary Ventilation; MVV

    Time frame: Change from Baseline respiratory muscle strength at 8 weeks.

    Participants were instructed to breathe in and out as quickly and forcefully as possible for 15 seconds.

  5. Breath Holding Time Test

    Time frame: Change from Baseline respiratory muscle strength at 8 weeks.

    Participants were instructed to inhale as deeply as possible, hold their breath for as long as possible, and then exhale through the mouth.

  6. Maximal Inspiratory Pressure; MIP

    Time frame: Change from Baseline respiratory muscle strength at 8 weeks.

    Participants were instructed to exhale fully to functional residual capacity (FRC), then place the mouthpiece securely and perform a maximal inspiratory effort sustained for 1-2 seconds.

  7. Maximal expiratory pressure; MEP

    Time frame: Change from Baseline respiratory muscle strength at 8 weeks.

    Participants inhaled fully to total lung capacity (TLC), maintained a tight seal on the mouthpiece, and then performed a maximal expiratory effort for 1-2 seconds.

Sponsors and collaborators

Lead sponsor

Chulalongkorn University

Other

Registry information

Official study title

Effects of Free Diving Breathing Training on Symptoms in Patients With Allergic Rhinitis

Important dates

Study start
2025
Primary completion
2026
Study completion
2026
First posted
Mar 6, 2026
Registry last updated
Mar 6, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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