DiaphragmNCT07007923
Recruitment of the Diaphragm and Sternocleidomastoid Muscle During Loaded Inspiration on Varying Sitting Support in Healthy Adults
An observational study of Diaphragm, run by Hong Kong Metropolitan University at 1 site in Hong Kong.
Trial summary
This is a cross-sectional obsessional study. This study explores how different sitting conditions affect two important muscles-the diaphragm and the sternocleidomastoid (SCM)-work during breathing exercises. The diaphragm is the main muscle for breathing, while the SCM helps when taking deeper breaths. Read more about this study
- Who is it for?
- Ages 18 to 35 yearsHealthy volunteers can take part
- Conditions the study is for
- Diaphragm
- How many people
- 45 participants
- Where
- 1 siteHong Kong
- Study dates
- 19 Jun 2025to 20 Apr 2026
- Phase
- Observational
- 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 to 35 years
- All sexes
- Healthy volunteers accepted
- Adult
Study population: aged 18-35 healthy young adults
Who may be able to join
- aged 18-35 years - No recent thoracic surgery in the past 6 months
- Absence in history of chronic respiratory illness
- Able to breathe spontaneously
- Conscious, able to follow instructions on the use of IMT device
Who cannot join
- with known cardiovascular, pulmonary or musculoskeletal disorders that would limit their functional capacity (E.g. Asthma, COPD)
- presence with respiratory symptoms over past 2 weeks
- pregnancy
- malignancy
- presence of neurological disorders (e.g. ALS, stroke)
- PCS/ MCS in SF-12 scores below 50
- Findings in spirometry suggesting presence of obstructive or restrictive disorders
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Hong Kong1 site
Hong Kong Metropolitan University Jockey Club Institute of Healthcare
Hong Kong
William Wai Nam Tsang, wntsang@hkmu.edu.hk
About this study
This is a cross-sectional obsessional study.
This study explores how different sitting conditions affect two important muscles-the diaphragm and the sternocleidomastoid (SCM)-work during breathing exercises. The diaphragm is the main muscle for breathing, while the SCM helps when taking deeper breaths. Understanding how these muscles interact while sitting under various conditions can help improve breathing training techniques.
Read more
The study's objectives are (1) to investigate the relationship between diaphragm thickness fraction with 4 different sitting conditions during loaded inspiration among healthy adults and (2) To investigate the relationship between SCM activity with 4 different sitting conditions during loaded inspiration among healthy adults.
This research will conduct healthy adults, who will be instructed to breathe against resistance provided by the IMT while sitting on four different conditions: a regular chair, a soft pad with feet on the ground, a soft pad with feet on two additional soft pads, and a single soft pad with both feet on one pad. By using ultrasound to measure how thick the diaphragm gets and surface electromyography (sEMG) to track SCM activity, the data will be gathered on how these muscles function under different conditions.
The goal is to find out if sitting on unstable surfaces, like soft pads, can enhance diaphragm use compared to a stable chair. These surfaces may change how effectively the diaphragm and SCM work together. This research could lead to better recommendations for inspiratory muscle training (IMT), which helps strengthen these muscles, especially for people with breathing difficulties.
By identifying how posture influences muscle recruitment during breathing exercises, hoping to contribute valuable insights that can improve rehabilitation programs for individuals with respiratory conditions.
Read the detailed description
Participant information sheets and consent form will be given and explained to participants prior to experiment. To ensure measurement consistency, one standardized assessor will be employed. Demographic data, including age, sex, exercise habit, and smoking history will be recorded. Health-related quality of life will be quantified by SF-12. Participants who score below 50 in PCS or MCS will be excluded from our study.
All eligible participants will undertake a standard spirometry test to obtain forced vital capacity (FVC), forced expiratory volume in one second (FEV1). Spirometry test will be performed 3 times, in accordance with guidelines recommended by the American Thoracic Society. Participants with findings of obstructive or restrictive disorders will be excluded. MIP will be obtained by a threshold device (S1breathe K5) under standard instruction. Before measuring MIP, specific instructions guiding participants to focus on diaphragm breathing will be instructed (one hand positioned on the subcostal region and allow air to go to the lower part of the chest where your hand is placed) to allow participants aware of the use of diaphragm during trials, therefore they can subconsciously deploy the technique in the subsequent trials. Participants will be allowed to perform 3 times (with nose-clip applied), with the best MIP will be recorded. The thickness of right diaphragm and SCM activity at maximum inspiration, maximum expiration, end-tidal inspiration, end-tidal expiration, and MIP were measured by ultrasonography and sEMG respectively.
Participants will then be instructed to perform IMT in different conditions in a randomized order, completing 4 sets 15 breaths, with a rest period of 5 mins between sets. 50% MIP will be calibrated at the POWERbreathe device with respect to each participant prior IMT. During each inspiratory pressure-targeted breath, simultaneous sEMG recording on the right SCM and ultrasonography of right hemi-diaphragm will be conducted. Participants's subjective exertion level will be recorded by Borg's Rate of Perceived Exertion Scale at the end of each set of recordings.
The POWERbreathe device requires 5 breaths to meet the targeted load. Following the manufacturer's instructions, participants will be instructed to perform with a sharp inspiration lasting 1-2s at each breath for reaching the required load. Each participant will be requested to complete 15 breaths, but only the data from 6th to 15th breaths will be included for analysis. The whole duration will take around 90 minutes. Password code will be used to guarantee anonymity and confidentiality for the data obtained.
- Conditions
- Diaphragm
- Keywords
- Diaphragmatic thickening fraction, Sternocleidomastoid muscles, inspiratory pressure
What is being measured
The primary outcome is the main question the study is designed to answer.
Diaphragmatic thickening fraction
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.
Measured: Through study completion, an average of 1 year
Secondary outcomes (2)
Muscle activation of the sternocleidomastoid muscle
Surface electromyography will be used to measure accessory inspiratory muscle (sternocleidomastoid muscles) activity during each inspiratory muscle training intensity.
Measured: Through study completion, an average of 1 year
Borg's scale
The Borg scale is widely used for measuring perceived exertion during physical activity. It can gauge how hard individuals are exerting while taking into account the individual's heart rate, breathing effort, and fatigue level. Participant's subjective experience would also gauge the score of the scale. The Borg RPE scale would be used to measure exertion during exercise as it has a high correlation with physiological measurements. It is quantified from 0 to 10, where 0 represents no symptoms, and 10 represents the maximum symptoms.
Measured: Through study completion, an average of 1 year
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Jun 2025
- Study start19 Jun 2025 (estimated)
- Primary completion31 Jul 2025 (estimated)
- Study completion20 Apr 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for DiaphragmStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case crossover
- Time perspective
- Cross-sectional
- Enrolment
- 45 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Hong Kong Metropolitan University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, LIU FANG, Hong Kong Metropolitan University
- Investigators
- William Tsang, Study director, Hong Kong Metropolitan University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07007923
- Sponsor's protocol ID
- No.HE-OT2023/13
- Status last verified
- May 2025
- First submitted
- 10 May 2025
- Last updated
- 6 Jun 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 6 Jun 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Recruitment of the Diaphragm and Sternocleidomastoid Muscle During Loaded Inspiration on Varying Sitting Support in Healthy Adults
- ClinicalTrials.gov ID
- NCT07007923
- Acronym / sponsor ID
- No.HE-OT2023/13
- Conditions
- Diaphragm
- Keywords
- Diaphragmatic thickening fraction, Sternocleidomastoid muscles, inspiratory pressure
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 45 participants (estimated)
- Lead sponsor
- Hong Kong Metropolitan UniversityUniversity, hospital or other
- Study start
- 19 Jun 2025 (estimated)
- Primary completion
- 31 Jul 2025 (estimated)
- Study completion
- 20 Apr 2026 (estimated)
- First posted
- 6 Jun 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a cross-sectional obsessional study.
This study explores how different sitting conditions affect two important muscles-the diaphragm and the sternocleidomastoid (SCM)-work during breathing exercises. The diaphragm is the main muscle for breathing, while the SCM helps when taking deeper breaths. Understanding how these muscles interact while sitting under various conditions can help improve breathing training techniques.
The study's objectives are (1) to investigate the relationship between diaphragm thickness fraction with 4 different sitting conditions during loaded inspiration among healthy adults and (2) To investigate the relationship between SCM activity with 4 different sitting conditions during loaded inspiration among healthy adults.
This research will conduct healthy adults, who will be instructed to breathe against resistance provided by the IMT while sitting on four different conditions: a regular chair, a soft pad with feet on the ground, a soft pad with feet on two additional soft pads, and a single soft pad with both feet on one pad. By using ultrasound to measure how thick the diaphragm gets and surface electromyography (sEMG) to track SCM activity, the data will be gathered on how these muscles function under different conditions.
The goal is to find out if sitting on unstable surfaces, like soft pads, can enhance diaphragm use compared to a stable chair. These surfaces may change how effectively the diaphragm and SCM work together. This research could lead to better recommendations for inspiratory muscle training (IMT), which helps strengthen these muscles, especially for people with breathing difficulties.
By identifying how posture influences muscle recruitment during breathing exercises, hoping to contribute valuable insights that can improve rehabilitation programs for individuals with respiratory conditions.
Detailed description
Participant information sheets and consent form will be given and explained to participants prior to experiment. To ensure measurement consistency, one standardized assessor will be employed. Demographic data, including age, sex, exercise habit, and smoking history will be recorded. Health-related quality of life will be quantified by SF-12. Participants who score below 50 in PCS or MCS will be excluded from our study.
All eligible participants will undertake a standard spirometry test to obtain forced vital capacity (FVC), forced expiratory volume in one second (FEV1). Spirometry test will be performed 3 times, in accordance with guidelines recommended by the American Thoracic Society. Participants with findings of obstructive or restrictive disorders will be excluded. MIP will be obtained by a threshold device (S1breathe K5) under standard instruction. Before measuring MIP, specific instructions guiding participants to focus on diaphragm breathing will be instructed (one hand positioned on the subcostal region and allow air to go to the lower part of the chest where your hand is placed) to allow participants aware of the use of diaphragm during trials, therefore they can subconsciously deploy the technique in the subsequent trials. Participants will be allowed to perform 3 times (with nose-clip applied), with the best MIP will be recorded. The thickness of right diaphragm and SCM activity at maximum inspiration, maximum expiration, end-tidal inspiration, end-tidal expiration, and MIP were measured by ultrasonography and sEMG respectively.
Participants will then be instructed to perform IMT in different conditions in a randomized order, completing 4 sets 15 breaths, with a rest period of 5 mins between sets. 50% MIP will be calibrated at the POWERbreathe device with respect to each participant prior IMT. During each inspiratory pressure-targeted breath, simultaneous sEMG recording on the right SCM and ultrasonography of right hemi-diaphragm will be conducted. Participants's subjective exertion level will be recorded by Borg's Rate of Perceived Exertion Scale at the end of each set of recordings.
The POWERbreathe device requires 5 breaths to meet the targeted load. Following the manufacturer's instructions, participants will be instructed to perform with a sharp inspiration lasting 1-2s at each breath for reaching the required load. Each participant will be requested to complete 15 breaths, but only the data from 6th to 15th breaths will be included for analysis. The whole duration will take around 90 minutes. Password code will be used to guarantee anonymity and confidentiality for the data obtained.
Study design
- Observational model
- Case crossover
- Time perspective
- Cross-sectional
Who may qualify
- Ages
- 18 to 35 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
- Study population
- aged 18-35 healthy young adults
Key inclusion criteria (4 listed)
- aged 18-35 years - No recent thoracic surgery in the past 6 months
- Absence in history of chronic respiratory illness
- Able to breathe spontaneously
- Conscious, able to follow instructions on the use of IMT device
Key exclusion criteria (7 listed)
- with known cardiovascular, pulmonary or musculoskeletal disorders that would limit their functional capacity (E.g. Asthma, COPD)
- presence with respiratory symptoms over past 2 weeks
- pregnancy
- malignancy
- presence of neurological disorders (e.g. ALS, stroke)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Diaphragmatic thickening fraction
Time frame: 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.
2 secondary outcomes
Muscle activation of the sternocleidomastoid muscle
Time frame: Through study completion, an average of 1 year
Borg's scale
Time frame: Through study completion, an average of 1 year
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Jun 2025.
- Individual participant dataSharing planned: Undecided
Related trials for Diaphragm
Active, not recruiting
Diaphragm Mobilization in Adolescent Idiopathic Scoliosis
Adolescent Idiopathic Scoliosis
Enrolling by invitationObservational study
North American Fetal Therapy Network Prospective Registry for Long-term Outcome Following Fetoscopic Endoluminal Tracheal Occlusion in Severe Left and Right Congenital Diaphragmatic Hernia
Congenital Diaphragmatic Hernia
Active, not recruitingObservational study
DIAPHRAGM STRENGTH AND LUNG VOLUMES
Mechanical Ventilation
Not yet recruiting
Magnesium Sulphate as an Adjuvant in Combined Costoclavicular Block and Suprascapular Block Versus Interscalene Block for Ambulatory Shoulder Arthroscopy
Postoperative Pain, Shoulder Arthroscopy
Recruiting
Familial Form of Carotid Web: a Doppler Ultrasound Study
Carotid Web
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
William Tsang study director
Hong Kong Metropolitan University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Diaphragm, run by Hong Kong Metropolitan University at 1 site in Hong Kong.
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 4 inclusion and 7 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: opening soon, as of the sponsor's last update on 6 Jun 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Hong Kong. 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?
Contact Yi On Mak, Bachelor of Physiotherapy (+85292328865, s1314212@live.hkmu.edu.hk), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Diaphragmatic thickening fraction (time frame: Through study completion, an average of 1 year). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 6 Jun 2025.