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NCT Number: NCT06627283

Effects of Respiratory Muscle Training on Tongue Muscle Function

This study aims to investigate the effects of respiratory muscle training on tongue muscle function in healthy subjects. We hypothesize that respiratory muscle training can improve strength and endurance of the tongue muscles.

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Key information

Conditions

Healthy

Age range

18 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

KULeuven, Leuven, Belgium

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About this study

In patient with obstructive sleep apnea, studies have shown that respiratory muscle training improved sleep-related outcomes in patients with obstructive sleep apnea (OSA). On the other hand, a recent study showed that expiratory muscle training improved tongue motor strength in patients with OSA. We hypothesize that respiratory muscle training (either Inspiratory Muscle Training (IMT) or Expiratory Muscle Training (EMT)) may elicit sleep-related improvement in patient with OSA through enhancement on tongue muscle function.

To investigate our hypothesis, we will first address this question in a population of healthy subjects. This study will therefore investigate the effects of respiratory muscle training on tongue muscle function in healthy subjects. The primary hypothesis is that the IMT program with lead to an increase in tongue strength compared to the control group. Other hypothesizes are that EMT, but not sham, will also lead to an increase in tongue strength, compared to the control group.

Who can participate

Healthy volunteers accepted: Yes

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

Inclusion criteria

Community ambulant adults between 18 to 65 years old as of testing day; able to understand French or Dutch (depending on the study's site of inclusion); BMI ≥ 18 and ≤ 30 kg/m².

Exclusion criteria

Any diagnosed neuromuscular or cardiorespiratory disease; diagnosed psychiatric or psychological disorders which could affect adherence to or comprehension of instructions; diagnosed eating disorders; previous or ongoing head and neck cancer; diagnosed OSA; presenting a high-risk of sleep-disordered breathing indicated by a NoSAS score of 8 or higher 32 or a STOP-Bang score of 3 or higher 33,34; resting heart rate (HR) > 100 beats per minute (bpm) or < 50 bpm; resting systolic blood pressure (SBP) > 140 or < 90 mmHg, diastolic blood pressure (DBP) > 90 or < 50 mmHg; oxygen saturation (SpO2) < 94% at rest on room air. Individuals with abnormal lung function, i.e., forced expiratory volume in 1 second (FEV1) ≤ 80%, forced vital capacity (FVC) ≤ 80%, and FEV1/FVC ≤ 70%, will also be excluded.

Treatment and study plan

IMT

Device

Description: A pressure threshold loading device will be used: the POWERbreathe Medic (load range 10-90 cmH2O). Participants will be instructed to exhale passively during normal tidal breathing through the training device (until functional residual capacity) and to perform deep inspirations against the external load. The first week, the resistance will be fixed at 30% of the baseline measured maximal inspiratory pressure (MIP). Participants will be instructed to increase the resistance by 10% of the baseline set resistance each week.

EMT

Device

A pressure threshold loading device will be used: the POWERbreathe Ex1 EMT Medic (load range 10-90 cmH2O) or POWERbreathe Ex1 EMT MR (load range 35-175 cmH2O) depending on their baseline MEP measurement. Participants will be instructed to inhale quietly during normal tidal breathing through the training device and to perform rapid and deep exhalation against the external load. The first week, the resistance will be fixed at 30% of the baseline measured MEP. Participants will be instructed to increase the resistance by 10% of the baseline set resistance each week.

SHAM

Device

A pressure threshold loading device will be used: the POWERbreathe Ex1 EMT Medic or MR, but with the resistance mechanism inside removed and replaced by a plastic ball. The same instructions will be given as for the EMT group, except that there will be no or minimal resistance (less than 6 cmH2O). There will be no change in resistance over the weeks.

Primary outcomes

  1. Tongue elevation strength

    Time frame: Measured two times: at baseline and after 8 weeks

    Tongue elevation strength (peak pressure) will be measured via the Iowa Oral Performance Instrument (IOPI).

Secondary outcomes

  1. Tongue protrustion strength

    Time frame: Measured two times: at baseline and after 8 weeks

    Tongue protrusion strength (peak pressure) will be measured via the Iowa Oral Performance Instrument (IOPI).

  2. Tongue elevation endurance

    Time frame: Measured two times: at baseline and after 8 weeks

    Tongue elevation endurance (50% of peak pressure) will be measured via the Iowa Oral Performance Instrument (IOPI).

  3. Tongue protrusion endurance

    Time frame: Measured two times: at baseline and after 8 weeks

    Tongue protrusion endurance (50% of peak pressure) will be measured via the Iowa Oral Performance Instrument (IOPI).

  4. Maximal inspiratory pressure

    Time frame: Measured two times: at baseline and after 8 weeks

    Maximal inspiratory pressure will be measured at functional residual capacity (FRC)

  5. Maximal expiratory pressure

    Time frame: Measured two times: at baseline and after 8 weeks

    Maximal expiratory pressure will be measured at total lung capacity (TLC)

  6. Snoring intensity

    Time frame: Measured two times: at baseline and after 8 weeks

    The participants' bed partners (if applicable) will be asked to rate their partner´s snoring using a Visual Analog Scale (VAS), which ranked the impact of snoring from 0 (no snoring) to 10 (intolerable).

  7. Tongue base thickness

    Time frame: Measured two times: at baseline and after 8 weeks

    This measurement will be performed with a portable ultrasound machine

  8. Total sagittal thickness

    Time frame: Measured two times: at baseline and after 8 weeks

    This measurement will be performed with a portable ultrasound machine

  9. Lateral pharyngeal wall thickness

    Time frame: Measured two times: at baseline and after 8 weeks

    This measurement will be performed with a portable ultrasound machine

  10. Snoring duration

    Time frame: Measured two times: at baseline and after 8 weeks

    This recording will be conducted using the standard microphone application installed on the participant's personal phone and through the use of the free, already validated in studies, SnoreLab application.

Study contacts

Contact information is provided by the study sponsor or research team.

William Poncin

CONTACT

[email protected]

+3227642316

Sponsors and collaborators

Lead sponsor

Université Catholique de Louvain

Other

Registry information

Official study title

Effects of Respiratory Muscle Training on Tongue Muscle Function in Healthy Subjects, a Randomized Controlled Trial.

Important dates

Study start
2024
Primary completion
2026
Study completion
2026
First posted
Oct 4, 2024
Registry last updated
Apr 29, 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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