Change in Maximal Oxygen Uptake (VO₂Max)NCT07193108
The 30-15 Intermittent Fitness Test Provides Superior Sport-Specific Sensitivity to Treadmill Testing in Elite Female Footballers
A study testing 30-15 Intermittent Fitness Test in people with Change in Maximal Oxygen Uptake (VO₂Max), run by Gümüşhane Universıty at 1 site in Turkey (Türkiye).
Trial summary
This study compares the acute aerobic, metabolic, and threshold-related physiological responses elicited by the 30-15 Intermittent Fitness Test (30-15IFT) and a treadmill-based incremental running test in elite female football players. Read more about this study
- Who is it for?
- Ages 18 to 30 years, women onlyHealthy volunteers can take part
- Conditions the study is for
- Change in Maximal Oxygen Uptake (VO₂Max)
- What is being tested?
- 30-15 Intermittent Fitness Test
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 20 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 5 Mar 2025to 20 May 2025
- 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 30 years
- Women only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Female football players aged 18-35 years
- Competing in the Turkish Women's Super League
- Minimum of 3 years of professional football experience,
- Full participation in training and matches during the previous 6 months,
- Ability to perform maximal exercise testing
Who cannot join
- Musculoskeletal injury affecting performance within the last 3 months,
- Diagnosed cardiovascular, metabolic, or respiratory disease,
- Any condition limiting maximal physical effort
Trial locations and contacts
1 site in 1 country.
About this study
This study compares the acute aerobic, metabolic, and threshold-related physiological responses elicited by the 30-15 Intermittent Fitness Test (30-15IFT) and a treadmill-based incremental running test in elite female football players. Using a randomized crossover design, all participants completed both testing protocols with a 48-hour recovery period. Outcomes included maximal oxygen uptake, maximal running speed, heart rate responses, lactate-derived thresholds, metabolic tolerance indices, and recovery markers.
Read the detailed description
Laboratory-based treadmill tests are commonly used to assess aerobic capacity in football players; however, they lack sport-specific characteristics such as intermittent running, accelerations, and changes of direction. The 30-15 Intermittent Fitness Test (30-15IFT) has been proposed as a more ecologically valid field-based alternative.
Twenty-seven elite female football players competing in the Turkish Women's Super League completed both the 30-15IFT and a standardized treadmill incremental protocol in a randomized crossover design. Tests were separated by 48 hours and performed under controlled environmental conditions. Physiological variables including VO₂max, maximal running speed, maximal heart rate, respiratory exchange ratio, lactate-derived thresholds (OBLA), metabolic load-dependent tolerance, and post-exercise recovery markers were assessed using breath-by-breath gas analysis, heart rate monitoring, and capillary blood lactate sampling.
The study aims to determine whether the 30-15IFT elicits more sensitive and sport-specific physiological responses compared with treadmill testing, thereby supporting its use in performance monitoring and individualized training prescription in elite women's football.
- Conditions
- Change in Maximal Oxygen Uptake (VO₂Max)
- Being tested
- 30-15 Intermittent Fitness Test, Control
- Keywords
- aerobic capacity, intermittent fitness assessment, women's football, metabolic response
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
30-15 Intermittent Fitness TestOther
Participants performed the 30-15 Intermittent Fitness Test consisting of 30-second running bouts interspersed with 15-second passive recovery periods, with progressive increases in running speed until volitional exhaustion.
ControlOther
Inspiratory Muscle Warm-Up Non-treated group, Control
| Study group | Role | What they receive |
|---|---|---|
| 30-15 Intermittent Fitness Test (30-15IFT) | Experimental | Participants performed the 30-15 Intermittent Fitness Test consisting of 30-second running bouts interspersed with 15-second passive recovery periods, with progressive increases in running speed until volitional exhaustion. Receives: Other: 30-15 Intermittent Fitness Test; Other: Control |
| CONTROL | No intervention | Inspiratory Muscle Warm-Up Non-treated group, Control |
What is being measured
The primary outcome is the main question the study is designed to answer.
Maximal Running Speed (MRS)
Highest running speed achieved during each protocol.
Measured: DAY 1
Maximal Oxygen Uptake (VO₂max)
Maximal oxygen uptake measured via breath-by-breath gas analysis.
Measured: Day 1
Secondary outcomes (3)
body composition
Body composition (BMI)
Measured: 1 Day
Maximal Heart Rate (HRmax)
Peak heart rate achieved during each test.
Measured: 1 Day
Maximal Oxygen Uptake (VO₂max)
Maximal oxygen uptake measured via breath-by-breath gas analysis.
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 posted25 Sep 2025
- Study start5 Mar 2025
- Primary completion15 Mar 2025
- Study completion20 May 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Change in Maximal Oxygen Uptake (VO₂Max)Studies 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
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- This study used a randomized crossover design in which all participants completed both the 30-15 Intermittent Fitness Test and a treadmill-based incremental running test. The order of the test protocols was randomized, and a 48-hour recovery period was implemented between sessions to minimize carryover effects. Physiological responses were compared within participants across the two testing conditions.
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 20 participants (actual)
Sponsor and investigators
- Lead sponsor
- Gümüşhane Universıty
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Coşkun YILMAZ, Gümüşhane Universıty
- Investigators
- coşkun yılmaz, associate professor, Principal investigator, Gümüşhane Universıty
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07193108
- Sponsor's protocol ID
- 2025-0451
- Status last verified
- Feb 2026
- First submitted
- 12 Sep 2025
- Last updated
- 6 Feb 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 6 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The 30-15 Intermittent Fitness Test Provides Superior Sport-Specific Sensitivity to Treadmill Testing in Elite Female Footballers
- ClinicalTrials.gov ID
- NCT07193108
- Acronym / sponsor ID
- 2025-0451
- Conditions
- Change in Maximal Oxygen Uptake (VO₂Max)
- Keywords
- aerobic capacity, intermittent fitness assessment, women's football, metabolic response
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 20 participants (actual)
- Lead sponsor
- Gümüşhane UniversıtyUniversity, hospital or other
- Study start
- 5 Mar 2025 (actual)
- Primary completion
- 15 Mar 2025 (actual)
- Study completion
- 20 May 2025 (actual)
- First posted
- 25 Sep 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 study compares the acute aerobic, metabolic, and threshold-related physiological responses elicited by the 30-15 Intermittent Fitness Test (30-15IFT) and a treadmill-based incremental running test in elite female football players. Using a randomized crossover design, all participants completed both testing protocols with a 48-hour recovery period. Outcomes included maximal oxygen uptake, maximal running speed, heart rate responses, lactate-derived thresholds, metabolic tolerance indices, and recovery markers.
Detailed description
Laboratory-based treadmill tests are commonly used to assess aerobic capacity in football players; however, they lack sport-specific characteristics such as intermittent running, accelerations, and changes of direction. The 30-15 Intermittent Fitness Test (30-15IFT) has been proposed as a more ecologically valid field-based alternative.
Twenty-seven elite female football players competing in the Turkish Women's Super League completed both the 30-15IFT and a standardized treadmill incremental protocol in a randomized crossover design. Tests were separated by 48 hours and performed under controlled environmental conditions. Physiological variables including VO₂max, maximal running speed, maximal heart rate, respiratory exchange ratio, lactate-derived thresholds (OBLA), metabolic load-dependent tolerance, and post-exercise recovery markers were assessed using breath-by-breath gas analysis, heart rate monitoring, and capillary blood lactate sampling.
The study aims to determine whether the 30-15IFT elicits more sensitive and sport-specific physiological responses compared with treadmill testing, thereby supporting its use in performance monitoring and individualized training prescription in elite women's football.
Study design
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (participant)
- Number of arms
- 2
- Model description
- This study used a randomized crossover design in which all participants completed both the 30-15 Intermittent Fitness Test and a treadmill-based incremental running test. The order of the test protocols was randomized, and a 48-hour recovery period was implemented between sessions to minimize carryover effects. Physiological responses were compared within participants across the two testing conditions.
| Arm | Type | Receives |
|---|---|---|
| 30-15 Intermittent Fitness Test (30-15IFT) | Experimental | Other: 30-15 Intermittent Fitness Test, Other: ControlParticipants performed the 30-15 Intermittent Fitness Test consisting of 30-second running bouts interspersed with 15-second passive recovery periods, with progressive increases in running speed until volitional exhaustion. |
| CONTROL | No intervention | –Inspiratory Muscle Warm-Up Non-treated group, Control |
Who may qualify
- Ages
- 18 to 30 years
- Sex
- Female only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Female football players aged 18-35 years
- Competing in the Turkish Women's Super League
- Minimum of 3 years of professional football experience,
- Full participation in training and matches during the previous 6 months,
- Ability to perform maximal exercise testing
Key exclusion criteria (3 listed)
- Musculoskeletal injury affecting performance within the last 3 months,
- Diagnosed cardiovascular, metabolic, or respiratory disease,
- Any condition limiting maximal physical effort
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 |
|---|---|---|
| 30-15 Intermittent Fitness TestParticipants performed the 30-15 Intermittent Fitness Test consisting of 30-second running bouts interspersed with 15-second passive recovery periods, with progressive increases in running speed until volitional exhaustion. | Other | 30-15 Intermittent Fitness Test (30-15IFT) |
| ControlInspiratory Muscle Warm-Up Non-treated group, Control | Other | 30-15 Intermittent Fitness Test (30-15IFT) |
Primary outcome
Maximal Running Speed (MRS)
Time frame: DAY 1
Highest running speed achieved during each protocol.
Maximal Oxygen Uptake (VO₂max)
Time frame: Day 1
Maximal oxygen uptake measured via breath-by-breath gas analysis.
3 secondary outcomes
body composition
Time frame: 1 Day
Maximal Heart Rate (HRmax)
Time frame: 1 Day
Maximal Oxygen Uptake (VO₂max)
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 6 Feb 2026.
- Individual participant dataSharing planned: Yes
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 yılmaz, associate professor principal investigator
Gümüşhane Universıty
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing 30-15 Intermittent Fitness Test in people with Change in Maximal Oxygen Uptake (VO₂Max), 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 5 inclusion and 3 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 6 Feb 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?
Maximal Running Speed (MRS) (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?
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 Feb 2026.