Diaphragm ThicknessNCT07795905
Abdominal Air-Pressure Resistance Versus Abdominal Weight Training for Improving Diaphragm Function in Healthy Young Adults
A study testing Abdominal Air Pressure Resistance Training and Abdominal Weight Training (AWT) in people with Diaphragm Thickness and Dyspnoea, run by University of Sharjah at 1 site in United Arab Emirates.
Trial summary
This study aims to compare the effects of abdominal air pressure resistance training, abdominal weight training, and breathing exercises on diaphragmatic strength, endurance, and physiological responses in young healthy adults. Read more about this study
- Who is it for?
- Ages 18 to 35 yearsHealthy volunteers can take part
- Conditions the study is for
- Diaphragm Thickness, Dyspnoea
- What is being tested?
- Abdominal Air Pressure Resistance Training and Abdominal Weight Training (AWT)
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 42 participants
- Where
- 1 siteUnited Arab Emirates
- Study dates
- 30 Nov 2026to 30 Mar 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 to 35 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- males and females with a body mass index (BMI) between 18.5 and 29.9 kg/m²
- non-smokers
- have not participated in structured respiratory muscle training within the previous six months
- able to understand the study procedures
- provide written informed consent.
Who cannot join
- have a known cardiopulmonary, neuromuscular, or significant metabolic disease
- experience a respiratory infection or respiratory symptoms within the preceding 2-3 weeks
- pregnant
- have undergone major abdominal or thoracic surgery within the previous six months
- have uncontrolled hypertension, significant gastroesophageal reflux disease (GERD), or any other condition that could make abdominal loading unsafe, as determined during the screening process.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United Arab Emirates1 site
University of Sharjah
Sharjah city
Kalyana Reddy, +971503614889, kreddy@sharjah.ac.ae
Khushi patel
About this study
Official title: Abdominal Air-Pressure Resistance Versus Abdominal Weight Training for Improving Diaphragm Function in Healthy Young Adults: A Pilot Randomized Controlled Trial Protocol
This study aims to compare the effects of abdominal air pressure resistance training, abdominal weight training, and breathing exercises on diaphragmatic strength, endurance, and physiological responses in young healthy adults.
Forty-two healthy adults aged 18-35 years will be randomly allocated to one of three groups: abdominal air pressure resistance training, abdominal weight training, or breathing exercises. Participants will complete supervised training sessions three times per week for eight weeks, with standardized breathing cadence, training volume, and therapist contact time across groups.
This trial will provide the first direct comparison of a programmable pneumatic abdominal loading method with traditional abdominal weight loading and standard breathing exercises in healthy young adults. The findings will help determine the relative effectiveness, tolerability, and safety of these interventions for enhancing diaphragmatic function. The results may contribute to the development of evidence-based respiratory muscle training strategies for rehabilitation, health promotion, and performance enhancement.
- Conditions
- Diaphragm Thickness, Dyspnoea
- Being tested
- Abdominal Air Pressure Resistance Training, Abdominal Weight Training (AWT), Breathing Exercise Control (BE)
- Keywords
- Cardiopulmonary rehabilitation, Diaphragm thickness, Respiratory muscle, Dyspnea
- Medical subject headings
- Dyspnea
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Abdominal Air Pressure Resistance TrainingOther
In the AAPR group, resisted diaphragmatic breathing will be performed using a pneumatic abdominal garment or cuff capable of delivering quantifiable air pressure. The abdominal binder was securely fitted around the participant's waist, while the manual sphygmomanometer cuff was positioned vertically over the epigastric region within the abdominal binder. The cuff was inflated to provide external resistance during diaphragmatic breathing. Care was taken to ensure that the cuff and binder did not exert excessive compression over the lower thoracic region or diaphragm, thereby avoiding mechanical restriction of diaphragmatic excursion and allowing participants to maintain their normal, unrestricted diaphragmatic breathing pattern throughout the intervention. Training will begin at a pressure eliciting moderate perceived breathing effort (Borg RPE) or within a predefined range of 5-10 cmH₂O. Pressure will be increased based on Borg exertion level of 5-7.
Abdominal Weight Training (AWT)Other
In the AWT group, diaphragmatic breathing will be performed with an external load applied to the anterior abdominal wall using a standardized sandbag or weight pack, with participants positioned in supine crook-lying. Load prescription will be implemented using a pre-specified method, which included either a fixed initial load of 2-5 kg with weekly increments of 0.5-1 kg as tolerated, an initial load corresponding to 3-5% of body mass with weekly progression, or load titration based on perceived exertion targeting a Borg RPE of 4-5 during training sets. Training volume, set duration, and rest intervals will be matched to those of the AAPR group. For each session, the load applied, perceived exertion, and symptom responses will be documented.
Breathing Exercise Control (BE)Other
In the BE control group, standardized diaphragmatic breathing combined with paced slow deep breathing will be performed without the application of external resistance. Training duration, breathing cadence, number of sets, and rest intervals will be matched to those used in the loaded intervention groups. Perceived exertion and symptom responses will be documented during each session.
| Study group | Role | What they receive |
|---|---|---|
| Abdominal Air Pressure Resistance Training (AAPR) | Experimental | In the AAPR group, resisted diaphragmatic breathing will be performed using a pneumatic abdominal garment or cuff capable of delivering quantifiable air pressure. The abdominal binder was securely fitted around the participant's waist, while the manual sphygmomanometer cuff was positioned vertically over the epigastric region within the abdominal binder. The cuff was inflated to provide external resistance during diaphragmatic breathing. Care was taken to ensure that the cuff and binder did not exert excessive compression over the lower thoracic region or diaphragm, thereby avoiding mechanical restriction of diaphragmatic excursion and allowing participants to maintain their normal, unrestricted diaphragmatic breathing pattern throughout the intervention. Training will begin at a pressure eliciting moderate perceived breathing effort (Borg RPE) or within a predefined range of 5-10 cmH₂O. Pressure will be increased based on Borg exertion level of 5-7, provided symptom and tolerance cri Receives: Other: Abdominal Air Pressure Resistance Training |
| Abdominal Weight Training (AWT) | Active comparator | The AWT group will perform resisted diaphragmatic breathing with a 3-5 kg sandbag positioned over the abdomen while lying in the supine position. Participants will be instructed to perform diaphragmatic breathing, allowing the abdomen to rise during inspiration and fall during expiration while minimizing chest movement. The sandbag load will be individually adjusted for each participant according to a perceived exertion level of 11-13 on the Rating of Perceived Exertion (RPE) scale. Training duration, number of sets and rest periods will be matched with AAPR group to have uniformity across the group. Receives: Other: Abdominal Weight Training (AWT) |
| Breathing Exercise Control (BE) | Active comparator | In the BE control group, standardized diaphragmatic breathing combined with paced slow deep breathing will be performed without the application of external resistance. Training duration, breathing cadence, number of sets, and rest intervals will be matched to those used in the loaded intervention groups. Perceived exertion and symptom responses will be documented during each session Receives: Other: Breathing Exercise Control (BE) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Diaphragm thickening fraction
Diaphragm thickness will be assessed using a portable ultrasound device (VERSANA PREMIER) operating in B-mode with a 10-MHz linear transducer. Standardized imaging settings, including gain, depth, and focus, were maintained throughout all examinations. Ultrasound measurements were conducted by a trained assessor who was blinded to participants' group assignments. With participants positioned supine, the transducer was placed over the right hemidiaphragm at the zone of apposition, located between the anterior and mid-axillary lines at the eighth to ninth intercostal space. Care was taken to apply minimal pressure with the probe to prevent compression of underlying tissues. Diaphragm thickness measurements were obtained at end-expiration, corresponding to residual volume (RV), and at end-inspiration, corresponding to total lung capacity (TLC). Each measurement was repeated three times with a minimum rest period of 30 seconds between trials, and the mean value was used for analysis.
Measured: baseline and at 8 weeks
Secondary outcomes (1)
Maximal inspiratory pressure
MIP will be measured using a calibrated respiratory pressure manometer in the supported sitting position. Participants will exhale to residual volume and perform maximal inspiration against an occluded airway. At least three maneuvers will be performed with ≥30 seconds rest, and the highest reproducible value will be recorded in cmH₂O.
Measured: baseline and at 8 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted31 Aug 2026
- Study start30 Nov 2026 (estimated)
- Primary completion30 Mar 2027 (estimated)
- Study completion30 Mar 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Diaphragm ThicknessStudies 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
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 42 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Sharjah
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Khushi Patel, University of Sharjah
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07795905
- Sponsor's protocol ID
- REC-26-01-21-03-PG
- Status last verified
- Oct 2026
- First submitted
- 26 Aug 2026
- Last updated
- 3 Nov 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 3 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Abdominal Air-Pressure Resistance Versus Abdominal Weight Training for Improving Diaphragm Function in Healthy Young Adults: A Pilot Randomized Controlled Trial Protocol
- ClinicalTrials.gov ID
- NCT07795905
- Acronym / sponsor ID
- REC-26-01-21-03-PG
- Conditions
- Diaphragm Thickness, Dyspnoea
- Keywords
- Cardiopulmonary rehabilitation, Diaphragm thickness, Respiratory muscle, Dyspnea
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 42 participants (estimated)
- Lead sponsor
- University of SharjahUniversity, hospital or other
- Study start
- 30 Nov 2026 (estimated)
- Primary completion
- 30 Mar 2027 (estimated)
- Study completion
- 30 Mar 2027 (estimated)
- First posted
- 31 Aug 2026 (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 study aims to compare the effects of abdominal air pressure resistance training, abdominal weight training, and breathing exercises on diaphragmatic strength, endurance, and physiological responses in young healthy adults.
Forty-two healthy adults aged 18-35 years will be randomly allocated to one of three groups: abdominal air pressure resistance training, abdominal weight training, or breathing exercises. Participants will complete supervised training sessions three times per week for eight weeks, with standardized breathing cadence, training volume, and therapist contact time across groups.
This trial will provide the first direct comparison of a programmable pneumatic abdominal loading method with traditional abdominal weight loading and standard breathing exercises in healthy young adults. The findings will help determine the relative effectiveness, tolerability, and safety of these interventions for enhancing diaphragmatic function. The results may contribute to the development of evidence-based respiratory muscle training strategies for rehabilitation, health promotion, and performance enhancement.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Abdominal Air Pressure Resistance Training (AAPR) | Experimental | Other: Abdominal Air Pressure Resistance TrainingIn the AAPR group, resisted diaphragmatic breathing will be performed using a pneumatic abdominal garment or cuff capable of delivering quantifiable air pressure. The abdominal binder was securely fitted around the participant's waist, while the manual sphygmomanometer cuff was positioned vertically over the epigastric region within the abdominal binder. The cuff was inflated to provide external resistance during diaphragmatic breathing. Care was taken to ensure that the cuff and binder did not exert excessive compression over the lower thoracic region or diaphragm, thereby avoiding mechanical restriction of diaphragmatic excursion and allowing participants to maintain their normal, unrestricted diaphragmatic breathing pattern throughout the intervention. Training will begin at a pressure eliciting moderate perceived breathing effort (Borg RPE) or within a predefined range of 5-10 cmH₂O. Pressure will be increased based on Borg exertion level of 5-7, provided symptom and tolerance cri |
| Abdominal Weight Training (AWT) | Active comparator | Other: Abdominal Weight Training (AWT)The AWT group will perform resisted diaphragmatic breathing with a 3-5 kg sandbag positioned over the abdomen while lying in the supine position. Participants will be instructed to perform diaphragmatic breathing, allowing the abdomen to rise during inspiration and fall during expiration while minimizing chest movement. The sandbag load will be individually adjusted for each participant according to a perceived exertion level of 11-13 on the Rating of Perceived Exertion (RPE) scale. Training duration, number of sets and rest periods will be matched with AAPR group to have uniformity across the group. |
| Breathing Exercise Control (BE) | Active comparator | Other: Breathing Exercise Control (BE)In the BE control group, standardized diaphragmatic breathing combined with paced slow deep breathing will be performed without the application of external resistance. Training duration, breathing cadence, number of sets, and rest intervals will be matched to those used in the loaded intervention groups. Perceived exertion and symptom responses will be documented during each session |
Who may qualify
- Ages
- 18 to 35 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- males and females with a body mass index (BMI) between 18.5 and 29.9 kg/m²
- non-smokers
- have not participated in structured respiratory muscle training within the previous six months
- able to understand the study procedures
- provide written informed consent.
Key exclusion criteria (5 listed)
- have a known cardiopulmonary, neuromuscular, or significant metabolic disease
- experience a respiratory infection or respiratory symptoms within the preceding 2-3 weeks
- pregnant
- have undergone major abdominal or thoracic surgery within the previous six months
- have uncontrolled hypertension, significant gastroesophageal reflux disease (GERD), or any other condition that could make abdominal loading unsafe, as determined during the screening process.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Abdominal Air Pressure Resistance TrainingIn the AAPR group, resisted diaphragmatic breathing will be performed using a pneumatic abdominal garment or cuff capable of delivering quantifiable air pressure. The abdominal binder was securely fitted around the participant's waist, while the manual sphygmomanometer cuff was positioned vertically over the epigastric region within the abdominal binder. The cuff was inflated to provide external resistance during diaphragmatic breathing. Care was taken to ensure that the cuff and binder did not exert excessive compression over the lower thoracic region or diaphragm, thereby avoiding mechanical restriction of diaphragmatic excursion and allowing participants to maintain their normal, unrestricted diaphragmatic breathing pattern throughout the intervention. Training will begin at a pressure eliciting moderate perceived breathing effort (Borg RPE) or within a predefined range of 5-10 cmH₂O. Pressure will be increased based on Borg exertion level of 5-7. | Other | Abdominal Air Pressure Resistance Training (AAPR) |
| Abdominal Weight Training (AWT)In the AWT group, diaphragmatic breathing will be performed with an external load applied to the anterior abdominal wall using a standardized sandbag or weight pack, with participants positioned in supine crook-lying. Load prescription will be implemented using a pre-specified method, which included either a fixed initial load of 2-5 kg with weekly increments of 0.5-1 kg as tolerated, an initial load corresponding to 3-5% of body mass with weekly progression, or load titration based on perceived exertion targeting a Borg RPE of 4-5 during training sets. Training volume, set duration, and rest intervals will be matched to those of the AAPR group. For each session, the load applied, perceived exertion, and symptom responses will be documented. | Other | Abdominal Weight Training (AWT) |
| Breathing Exercise Control (BE)In the BE control group, standardized diaphragmatic breathing combined with paced slow deep breathing will be performed without the application of external resistance. Training duration, breathing cadence, number of sets, and rest intervals will be matched to those used in the loaded intervention groups. Perceived exertion and symptom responses will be documented during each session. | Other | Breathing Exercise Control (BE) |
Primary outcome
Diaphragm thickening fraction
Time frame: baseline and at 8 weeks
Diaphragm thickness will be assessed using a portable ultrasound device (VERSANA PREMIER) operating in B-mode with a 10-MHz linear transducer. Standardized imaging settings, including gain, depth, and focus, were maintained throughout all examinations. Ultrasound measurements were conducted by a trained assessor who was blinded to participants' group assignments. With participants positioned supine, the transducer was placed over the right hemidiaphragm at the zone of apposition, located between the anterior and mid-axillary lines at the eighth to ninth intercostal space. Care was taken to apply minimal pressure with the probe to prevent compression of underlying tissues. Diaphragm thickness measurements were obtained at end-expiration, corresponding to residual volume (RV), and at end-inspiration, corresponding to total lung capacity (TLC). Each measurement was repeated three times with a minimum rest period of 30 seconds between trials, and the mean value was used for analysis.
1 secondary outcome
Maximal inspiratory pressure
Time frame: baseline and at 8 weeks
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 3 Nov 2026.
- Individual participant dataSharing planned: No
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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.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Abdominal Air Pressure Resistance Training and Abdominal Weight Training (AWT) in people with Diaphragm Thickness and Dyspnoea, run by University of Sharjah at 1 site in United Arab Emirates.
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: opening soon, as of the sponsor's last update on 3 Nov 2026. 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 United Arab Emirates. 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 Kalyana Reddy (+971503614889, kreddy@sharjah.ac.ae), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Diaphragm thickening fraction (time frame: baseline and at 8 weeks). 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 3 Nov 2026.