The Impact of Diaphragmatic Breathing Instructions and Inspiratory Pressures on Diaphragm Contraction in Healthy Adults
- Conditions
- Diaphragm
- Interventions
- Diagnostic Test: Various intensities of inspiratory muscle training
- Registration Number
- NCT06347549
- Lead Sponsor
- Hong Kong Metropolitan University
- Brief Summary
This is a cross-sectional obsessional study.
This study aims (1) to investigate the relationship between sternocleidomastoid muscle recruitment and diaphragm thickness fraction during increasing inspiratory resistance in healthy adults; (2) to compare diaphragmatic and sternocleidomastoid muscle recruitment patterns with and without a standard diaphragmatic breathing instruction with increasing inspiratory resistance in healthy adults.
Participants will be asked to breathe through a pressure threshold inspiratory loading device under different inspiratory resistances with and without a standard diaphragmatic breathing instruction. sternocleidomastoid muscle activity will be measured with surface electromyography, and diaphragm thickness will be assessed with ultrasonography.
- Detailed Description
Upon arrival at the laboratory, eligible participants will first perform a standard spirometry lung function test. The maximum inspiratory pressure (MIP) will be determined with a pressure threshold inspiratory loading device (POWERbreathe, K2). Each participant will then be instructed to use the device to perform, in random order, 10 breaths at an inspiratory intensity of 30%, 40%, 50%, 60%, 70%, and 80% MIP. A rest period of 15 minutes will be allowed between each inspiratory pressure set of 10 breaths. Simultaneous surface electromyographic (sEMG) recording of the right sternocleidomastoid muscle and ultrasound of right diaphragmatic thickness will be conducted during each breath.
The entire recording procedure will be repeated on a separate day. During the repeat measurements, participants will be provided with specific breathing instruction to focus on the use of the diaphragm and to inhale air to the lower part of the chest. Practice trials will be conducted to ensure participant's understanding of diaphragmatic breathing.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 62
- Participants ≥18 years of age with normal health
- Pregnancy.
- Participants with known cardiovascular, pulmonary, musculoskeletal or psychiatric disorders.
- Participants with respiratory symptoms (from flu or other respiratory infection during the 2 weeks prior to measurements.
- Participants can not cooperate the maximal inspiratory pressure measurement.
Study & Design
- Study Type
- OBSERVATIONAL
- Study Design
- Not specified
- Arm && Interventions
Group Intervention Description Healthy adults Various intensities of inspiratory muscle training Participants ≥18 years of age with normal health will be recruited in this study.
- Primary Outcome Measures
Name Time Method Diaphragmatic thickening fraction Through study completion, an average of 1 year Diaphragmatic thickening fraction is determined by "(thickness of the diaphragm at end inspiratory - thickness at end expiratory)/thickness at end expiratory". Diaphragmatic thickness will be measured by ultrasonography.
- Secondary Outcome Measures
Name Time Method Muscle activation of the sternocleidomastoid muscle Through study completion, an average of 1 year Surface electromyography will be used to measure accessory inspiratory muscle (sternocleidomastoid muscles) activity during each inspiratory muscle training intensity.
Perceived Exertion Borg scale Through study completion, an average of 1 year This is a vertical scale quantified from 0 to 10, where 0 represents no symptoms, and 10 represents the maximum symptoms. The Borg score provides an individual measurement of the exercise intensity.
Trial Locations
- Locations (1)
Hong Kong Metropolitan University
🇨🇳Hong Kong, None Selected, China