Exercise PhysiologyIWU and 1RMNCT07390149
Acute Effects of Inspiratory Muscle Warm-up on Muscular Performance and Pulmonary Function in Natural Bodybuilders
A study testing IWU in people with Exercise Physiology and Sports Performance, run by Gümüşhane Universıty at 1 site in Turkey (Türkiye).
Trial summary
The present study aims to investigate the acute effects of inspiratory muscle warm-up (IWU) on 1RM performance in professional natural bodybuilders. The hypothesis is that IWU will lead to an increase in the pressure-generating capacity of the inspiratory muscles, thereby resulting in improved 1RM strength… Read more about this study
- Who is it for?
- Ages 18 to 35 years, men onlyHealthy volunteers can take part
- Conditions the study is for
- Exercise Physiology, Sports Performance
- What is being tested?
- IWU
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 27 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 5 Jan 2025to 5 Jan 2026
- Phase
- Interventional
- Are there results?
- None posted in the registry
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
- Men only
- Healthy volunteers accepted
- Adult
Who may be able to join
- They were professional natural bodybuilders with less than three years of experience. ,
- Male professional natural bodybuilders aged 18-35 years
- --Full participation in training and matches during the previous 6 months,
- Ability to perform maximal exercise testing
Who cannot join
- Individuals were deemed ineligible on the basis of a medical history that included any chronic or acute respiratory disease.
- Individuals were considered ineligible if they were taking any prescription medication that could affect their response to exercise.
- In accordance with the stipulated criteria, individuals were deemed to be ineligible for participation in the study if they had a history of current smoking or had smoked within the past year.
- Individuals were considered ineligible for participation in the study if they had participated in similar studies within the previous six months.
- Prior to participation, all individuals were required to sign a formal waiver, thereby affirming their adherence to the World Anti-Doping Agency Code.
Trial locations and contacts
1 site in 1 country.
Turkey (Türkiye)1 site
Gumushane Univetsity
Gümüşhane, Gümüşhane Province, (542) 442-7444
About this study
The present study aims to investigate the acute effects of inspiratory muscle warm-up (IWU) on 1RM performance in professional natural bodybuilders. The hypothesis is that IWU will lead to an increase in the pressure-generating capacity of the inspiratory muscles, thereby resulting in improved 1RM strength performance. The anticipated findings are expected to contribute not only to the enhancement of maximal strength performance but also to the improvement of exercise efficiency through increased respiratory muscle endurance. It is submitted that these outcomes may ultimately provide insights into the long-term sustainability of professional athletes' performance.
Twenty male athletes who had competed in national and international professional natural bodybuilding competitions were recruited for this study. The participants had an average experience in natural bodybuilding of 3.21 years, with a standard deviation of ± 1.44 years, and trained for more than five hours per week. The data collection period commenced in July 2025. The study was designed as a randomized controlled experimental trial. Participants were randomly assigned to two groups by a computerized program at three visits after the trial, based on their first measurement: inspiratory warm-up (IWU) group or control (CON) group.
Read the detailed description
The data collection period occurred between the 1st and 6th of July 2025. Prior to their involvement in the study, all subjects provided both verbal and written informed consent. Participants were invited to visit the laboratory on three separate occasions. During the preliminary visit, the subjects underwent a series of pulmonary function tests (PFTs). These included measurements of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP). The participants were also subjected to 1RM testing and three practice trials of both the inspiratory warm-up and general training warm-up procedures [14]. On the second occasion, the PFT and MIP-MEP tests were conducted without any warm-up protocols, followed by the assessment of 1RM performance. On the third occasion, the participants were divided into two groups: the experimental group (IWU), which performed both inspiratory muscle and general warm-up exercises, and the control group (CON), which performed only the general warm-up. Each group comprised ten professional male natural bodybuilders. PFT and MIP-MEP tests were reassessed, and 1RM performance was measured immediately following the IWU intervention. In order to control for circadian variations, all laboratory visits were conducted at the same time of day (between 09:00 and 12:00). Participants were notified 72 hours in advance of each visit and were instructed to refrain from high-intensity physical activity during that period. It was determined that a recovery period of 72 hours should be observed between each testing session.
- Conditions
- Exercise Physiology, Sports Performance
- Being tested
- IWU, Control
- Keywords
- acute interventions, human physiology, inspiratory muscle warm-up, exercise performance, bodybuilders, 1RM
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
IWUOther
Also called Inspiratory muscle warm-up
The IWU group performed both inspiratory muscle warm-up and standard exercise warm-up.
ControlOther
The CON group performed only the standard warm-up.
| Study group | Role | What they receive |
|---|---|---|
| IWU | Other | The IWU group performed both inspiratory muscle warm-up and standard exercise warm-up. Receives: Other: IWU; Other: Control |
| Control Group | Other | The CON group performed only the standard warm-up. Receives: Other: IWU; Other: Control |
What is being measured
The primary outcome is the main question the study is designed to answer.
1RM
One-Repetition maximum (1RM) bench press performance
Measured: Day 1
maximal inspiratory pressures (MIP )
maximal inspiratory pressures (MIP )
Measured: Day 1
Secondary outcomes (5)
maximal expiratory pressures (MEP)
maximal expiratory pressures (MEP)
Measured: Day 1
Forced vital capacity (FVC)
Pulmonary function parameter, including forced vital capacity (FVC), the total volume of air exhaled forcefully after a maximal deep inhalation, were measured using a MGF Diagnostics CPFS/D USB spirometer
Measured: Day 1
forced expiratory volume in one second (FEV1)
Pulmonary function parameter, including forced vital capacity (FEV1), the total volume of air exhaled forcefully after a maximal deep inhalation, were measured using a MGF Diagnostics CPFS/D USB spirometer
Measured: Day 1
FEV1/FVC ratio (Tiffeneau index)
Pulmonary function parameter, including forced vital capacity (FEV1/FVC), the total volume of air exhaled forcefully after a maximal deep inhalation, were measured using a MGF Diagnostics CPFS/D USB spirometer
Measured: Day 1
peak expiratory flow (PEF)
Pulmonary function parameter, including forced vital capacity (FVC), the total volume of air exhaled forcefully after a maximal deep inhalation, were measured using a MGF Diagnostics CPFS/D USB spirometer
Measured: Day 1
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Feb 2026
- Study start5 Jan 2025
- Primary completion15 Apr 2025
- Study completion5 Jan 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Exercise PhysiologyStudies 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
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- This study used a randomized, parallel-group design. Participants were randomly allocated to either the inspiratory warm-up (IWU) group or the control (CON) group. All participants completed baseline assessments prior to randomization and remained in their assigned group throughout the study. No crossover between conditions was implemented. Outcome measures were assessed across multiple visits to evaluate pre- and post-intervention responses within each group.
- Masking
- None (open label)
- Enrolment
- 27 participants (actual)
Sponsor and investigators
- Lead sponsor
- Gümüşhane Universıty
- Sponsor type
- University, hospital or other
- Collaborators
- Çankırı Karatekin University
- Responsible party
- Principal investigator, Coşkun YILMAZ, Gümüşhane Universıty
- Investigators
- Coşkun YILMAZ, associate professor, Study chair, Gümüşhane Üniversity
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07390149
- Sponsor's protocol ID
- 2025/0014
- Acronym
- IWU and 1RM
- Status last verified
- May 2026
- First submitted
- 18 Jan 2026
- Last updated
- 7 May 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data (IPD) will not be shared because the dataset consists of a small sample of elite athletes, and sharing de-identified data could still pose a risk of participant re-identification. In addition, no data-sharing agreement or participant consent for IPD sharing was established at the time of study design. Aggregate data supporting the findings are reported within the published article.
Publications
Ceylan T, Ceylan L, Yilmaz C, Badau A, Kucuk H. Acute effects of inspiratory muscle warm-up on muscular performance and pulmonary function in natural male bodybuilders. BMC Sports Sci Med Rehabil. 2026 Jun 30. doi: 10.1186/s13102-026-01816-4. Online ahead of print.
PubMed 42380951
Study at a glance
From the registry record, last updated by the sponsor on 7 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Acute Effects of Inspiratory Muscle Warm-up on Muscular Performance and Pulmonary Function in Natural Bodybuilders
- ClinicalTrials.gov ID
- NCT07390149
- Acronym / sponsor ID
- IWU and 1RM / 2025/0014
- Conditions
- Exercise Physiology, Sports Performance
- Keywords
- acute interventions, human physiology, inspiratory muscle warm-up, exercise performance, bodybuilders, 1RM
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 27 participants (actual)
- Lead sponsor
- Gümüşhane UniversıtyUniversity, hospital or other
- Collaborators
- Çankırı Karatekin University
- Study start
- 5 Jan 2025 (actual)
- Primary completion
- 15 Apr 2025 (actual)
- Study completion
- 5 Jan 2026 (actual)
- First posted
- 5 Feb 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.
The present study aims to investigate the acute effects of inspiratory muscle warm-up (IWU) on 1RM performance in professional natural bodybuilders. The hypothesis is that IWU will lead to an increase in the pressure-generating capacity of the inspiratory muscles, thereby resulting in improved 1RM strength performance. The anticipated findings are expected to contribute not only to the enhancement of maximal strength performance but also to the improvement of exercise efficiency through increased respiratory muscle endurance. It is submitted that these outcomes may ultimately provide insights into the long-term sustainability of professional athletes' performance.
Twenty male athletes who had competed in national and international professional natural bodybuilding competitions were recruited for this study. The participants had an average experience in natural bodybuilding of 3.21 years, with a standard deviation of ± 1.44 years, and trained for more than five hours per week. The data collection period commenced in July 2025. The study was designed as a randomized controlled experimental trial. Participants were randomly assigned to two groups by a computerized program at three visits after the trial, based on their first measurement: inspiratory warm-up (IWU) group or control (CON) group.
Detailed description
The data collection period occurred between the 1st and 6th of July 2025. Prior to their involvement in the study, all subjects provided both verbal and written informed consent. Participants were invited to visit the laboratory on three separate occasions. During the preliminary visit, the subjects underwent a series of pulmonary function tests (PFTs). These included measurements of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP). The participants were also subjected to 1RM testing and three practice trials of both the inspiratory warm-up and general training warm-up procedures [14]. On the second occasion, the PFT and MIP-MEP tests were conducted without any warm-up protocols, followed by the assessment of 1RM performance. On the third occasion, the participants were divided into two groups: the experimental group (IWU), which performed both inspiratory muscle and general warm-up exercises, and the control group (CON), which performed only the general warm-up. Each group comprised ten professional male natural bodybuilders. PFT and MIP-MEP tests were reassessed, and 1RM performance was measured immediately following the IWU intervention. In order to control for circadian variations, all laboratory visits were conducted at the same time of day (between 09:00 and 12:00). Participants were notified 72 hours in advance of each visit and were instructed to refrain from high-intensity physical activity during that period. It was determined that a recovery period of 72 hours should be observed between each testing session.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- This study used a randomized, parallel-group design. Participants were randomly allocated to either the inspiratory warm-up (IWU) group or the control (CON) group. All participants completed baseline assessments prior to randomization and remained in their assigned group throughout the study. No crossover between conditions was implemented. Outcome measures were assessed across multiple visits to evaluate pre- and post-intervention responses within each group.
| Arm | Type | Receives |
|---|---|---|
| IWU | Other | Other: IWU, Other: ControlThe IWU group performed both inspiratory muscle warm-up and standard exercise warm-up. |
| Control Group | Other | Other: IWU, Other: ControlThe CON group performed only the standard warm-up. |
Who may qualify
- Ages
- 18 to 35 years
- Sex
- Male only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (4 listed)
- They were professional natural bodybuilders with less than three years of experience. ,
- Male professional natural bodybuilders aged 18-35 years
- --Full participation in training and matches during the previous 6 months,
- Ability to perform maximal exercise testing
Key exclusion criteria (5 listed)
- Individuals were deemed ineligible on the basis of a medical history that included any chronic or acute respiratory disease.
- Individuals were considered ineligible if they were taking any prescription medication that could affect their response to exercise.
- In accordance with the stipulated criteria, individuals were deemed to be ineligible for participation in the study if they had a history of current smoking or had smoked within the past year.
- Individuals were considered ineligible for participation in the study if they had participated in similar studies within the previous six months.
- Prior to participation, all individuals were required to sign a formal waiver, thereby affirming their adherence to the World Anti-Doping Agency Code.
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 |
|---|---|---|
| IWUAlso: Inspiratory muscle warm-upThe IWU group performed both inspiratory muscle warm-up and standard exercise warm-up. | Other | Control Group, IWU |
| ControlThe CON group performed only the standard warm-up. | Other | Control Group, IWU |
Primary outcome
1RM
Time frame: Day 1
One-Repetition maximum (1RM) bench press performance
maximal inspiratory pressures (MIP )
Time frame: Day 1
maximal inspiratory pressures (MIP )
5 secondary outcomes
maximal expiratory pressures (MEP)
Time frame: Day 1
Forced vital capacity (FVC)
Time frame: Day 1
forced expiratory volume in one second (FEV1)
Time frame: Day 1
FEV1/FVC ratio (Tiffeneau index)
Time frame: Day 1
peak expiratory flow (PEF)
Time frame: Day 1
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 7 May 2026.
- Derived from this study: PubMed 42380951Ceylan T, Ceylan L, Yilmaz C, Badau A, Kucuk H. Acute effects of inspiratory muscle warm-up on muscular performance and pulmonary function in natural male bodybuilders. BMC Sports Sci Med Rehabil. 2026 Jun 30. doi: 10.1186/s13102-026-01816-4. Online ahead of print.
- Individual participant dataSharing planned: No. Individual participant data (IPD) will not be shared because the dataset consists of a small sample of elite athletes, and sharing de-identified data could still pose a risk of participant re-identification. In addition, no data-sharing agreement or participant consent for IPD sharing was established at the time of study design. Aggregate data supporting the findings are reported within the published article.
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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. This study is not recruiting at the moment.
Coşkun YILMAZ, associate professor study chair
Gümüşhane Üniversity
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing IWU in people with Exercise Physiology and Sports Performance, run by Gümüşhane Universıty at 1 site in Turkey (Türkiye).
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 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: finished, as of the sponsor's last update on 7 May 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 Turkey (Türkiye). 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?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
1RM (time frame: Day 1). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07390149, which also lists 1 linked publication.
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 7 May 2026.