Athletic Performance CopyNCT07865819
Effects of Hamstring-Specific Training on Athletic Performance in Amateur and Professional Soccer Players
A study testing Hamstring-Specific Exercise Protocol (HSEP) in people with Athletic Performance Copy and Hamstring Muscle Strength Copy, run by Istanbul Gelisim University at 1 site in Turkey (Türkiye).
Trial summary
This randomized controlled trial aimed to investigate the effects of a 12-week hamstring-specific exercise protocol (HSEP) on athletic performance in professional and amateur male soccer players. A total of 144 soccer players participated in the study, including 72 professional and 72 amateur players. Read more about this study
- Who is it for?
- Ages 18 to 40 years, men onlyHealthy volunteers can take part
- Conditions the study is for
- Athletic Performance Copy, Hamstring Muscle Strength Copy
- What is being tested?
- Hamstring-Specific Exercise Protocol (HSEP)
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 144 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 14 May 2025to 6 Aug 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 40 years
- Men only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Male soccer players actively competing at a licensed professional or amateur level.
- Regular participation in soccer training (4-5 sessions per week) during the competitive season.
- No previous participation in a structured hamstring strengthening program. Being free from injury at the time of enrollment. Provision of written informed consent before participation.
Who cannot join
- Presence of an injury at the time of enrollment. Previous participation in a structured hamstring strengthening program. Not meeting the required licensed professional or amateur soccer participation criteria.
- Declining to provide written informed consent.
Trial locations and contacts
1 site in 1 country.
Turkey (Türkiye)1 site
Istanbul Gelisim University
Istanbul, Istanbul, 34710
About this study
Official title: The Chronic Effect of a Hamstring-Specific Exercise Protocol on Athletic Performance Indicators in Amateur and Professional Soccer Players: A Randomized Controlled Trial
This randomized controlled trial aimed to investigate the effects of a 12-week hamstring-specific exercise protocol (HSEP) on athletic performance in professional and amateur male soccer players.
A total of 144 soccer players participated in the study, including 72 professional and 72 amateur players. Participants were randomly assigned to four groups: professional training (n = 36), professional control (n = 36), amateur training (n = 36), and amateur control (n = 36).
Read more
The intervention groups performed a structured hamstring-specific exercise protocol consisting of three bodyweight exercises: the Diver, Glider, and Single-Leg Hip Bridge. The program was implemented twice weekly for 12 weeks alongside regular soccer training. Training volume was progressively increased throughout the intervention period. The control groups continued their usual soccer training without performing the additional hamstring-specific exercise protocol.
Athletic performance was assessed before and after the intervention using vertical jump and countermovement jump tests, the 30-15 Intermittent Fitness Test, one-repetition maximum squat and deadlift tests, eccentric hamstring strength measurements, and maximal sprint velocity assessments.
The primary purpose of this study was to determine whether adding a structured hamstring strengthening program to regular soccer training improves physical performance and whether professional and amateur soccer players respond differently to the intervention.
The findings may help physiotherapists, sports scientists, and strength and conditioning coaches better understand the role of hamstring-specific training in soccer performance.
- Being tested
- Hamstring-Specific Exercise Protocol (HSEP)
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Hamstring-Specific Exercise Protocol (HSEP)Behavioural
The hamstring-specific exercise protocol (HSEP) consisted of three bodyweight exercises: Diver, Glider, and Single-Leg Hip Bridge. The intervention was performed twice weekly for 12 consecutive weeks during the competitive season, in addition to regular soccer training. Each session began with a 10-minute general and dynamic warm-up. Training volume was progressively increased, with 3 sets of 12 repetitions during weeks 1-4, 3 sets of 16 repetitions during weeks 5-8, and 3 sets of 20 repetitions during weeks 9-12. All exercises were supervised by athletic performance coaches, with a supervision ratio of one coach per four players. The control groups continued their regular soccer training without receiving the additional HSEP intervention.
| Study group | Role | What they receive |
|---|---|---|
| Professional Training Group | Experimental | Professional male soccer players (n = 36) performed a 12-week hamstring-specific exercise protocol (HSEP) twice weekly in addition to their regular soccer training. The intervention consisted of three bodyweight exercises: Diver, Glider, and Single-Leg Hip Bridge. Training volume was progressively increased throughout the intervention period. Receives: Behavioral: Hamstring-Specific Exercise Protocol (HSEP) |
| Professional Control Group | No intervention | Professional male soccer players (n = 36) continued their regular soccer training and competitive match participation for 12 weeks without receiving the additional hamstring-specific exercise protocol. |
| Amateur Training Group | Experimental | Amateur male soccer players (n = 36) performed a 12-week hamstring-specific exercise protocol (HSEP) twice weekly in addition to their regular soccer training. The intervention consisted of three bodyweight exercises: Diver, Glider, and Single-Leg Hip Bridge. Training volume was progressively increased throughout the intervention period. Receives: Behavioral: Hamstring-Specific Exercise Protocol (HSEP) |
| Amateur Control Group | No intervention | Amateur male soccer players (n = 36) continued their regular soccer training and competitive match participation for 12 weeks without receiving the additional hamstring-specific exercise protocol. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Maximal Sprint Velocity
Maximal linear sprint velocity was assessed during a 60-meter maximal sprint test using a 10 Hz GPS device (Catapult Vector S7, Catapult Sports, Australia). Each participant completed two trials, and the highest recorded velocity (km/h) was used for analysis. Changes in maximal sprint velocity were determined by comparing baseline and post-intervention measurements.
Measured: Baseline and Week 12 (Post-intervention)
Secondary outcomes (9)
Change in Countermovement Jump Height
Countermovement jump (CMJ) performance was assessed using the Witty Microgate system. Participants performed maximal vertical jumps with their hands positioned on their hips throughout the movement. Two trials were performed, and mean jump height was recorded in centimeters (cm). Changes from baseline to post-intervention were analyzed.
Measured: Baseline and Week 12 (Post-intervention)
Change in Vertical Jump Height
Vertical jump (VJ) performance was measured using the Witty Microgate system. Participants performed maximal jumps from a half-squat position with approximately 90 degrees of knee flexion and free arm movement. The mean of the two best trials was recorded in centimeters (cm). Changes from baseline to post-intervention were assessed.
Measured: Baseline and Week 12 (Post-intervention)
Change in Estimated Maximal Oxygen Uptake (VO2max)
Maximal oxygen uptake (VO2max) was estimated using the 30-15 Intermittent Fitness Test (30-15 IFT). Estimated VO2max was calculated from final running velocity, age, sex, and body mass using the Buchheit equation. Results were expressed in mL/kg/min. VO2max was estimated rather than directly measured.
Measured: Baseline and Week 12 (Post-intervention)
Change in Final Velocity During the 30-15 Intermittent Fitness Test
Final running velocity (VIFT) was determined using the 30-15 Intermittent Fitness Test. The test consisted of 30-second shuttle runs interspersed with 15-second passive recovery periods. Running speed started at 8 km/h and increased by 0.5 km/h at each stage. The speed achieved during the last successfully completed stage was recorded in km/h.
Measured: Baseline and Week 12 (Post-intervention)
Change in Total Distance Covered During the 30-15 Intermittent Fitness Test
Intermittent running capacity was assessed using the 30-15 Intermittent Fitness Test. Participants performed progressively faster shuttle runs over a 40-meter course until they could no longer maintain the required running speed. Total distance covered during the test was recorded in meters (m).
Measured: Baseline and Week 12 (Post-intervention)
Change in Squat One-Repetition Maximum Strength
Maximum lower-body strength was evaluated using the squat one-repetition maximum (1RM) test. Participants performed progressively heavier squat attempts following a standardized warm-up. The heaviest load successfully lifted with the required technique was recorded in kilograms (kg).
Measured: Baseline and Week 12 (Post-intervention)
Change in Deadlift One-Repetition Maximum Strength
Maximum lower-body strength was assessed using the conventional deadlift one-repetition maximum (1RM) test. Following standardized warm-up sets, participants performed progressively heavier single-repetition attempts. The highest successfully completed load was recorded in kilograms (kg).
Measured: Baseline and Week 12 (Post-intervention)
Change in Right-Leg Maximal Eccentric Hamstring Force
Maximal eccentric knee flexor force of the right leg was measured using the NordBord system (VALD Performance, Australia) during a Nordic hamstring strength assessment. Force was recorded using integrated load cells at a sampling frequency of 50 Hz and expressed in newtons (N). Changes between baseline and post-intervention were analyzed.
Measured: Baseline and Week 12 (Post-intervention)
Change in Left-Leg Maximal Eccentric Hamstring Force
Maximal eccentric knee flexor force of the left leg was assessed using the NordBord system (VALD Performance, Australia). Participants completed a Nordic hamstring strength assessment, and maximal eccentric force was recorded in newtons (N) using integrated load cells operating at a sampling frequency of 50 Hz.
Measured: Baseline and Week 12 (Post-intervention)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Oct 2026
- Study start14 May 2025
- Primary completion6 Aug 2025
- Study completion6 Aug 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Athletic Performance CopyStudies 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
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 144 participants (actual)
Sponsor and investigators
- Lead sponsor
- Istanbul Gelisim University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Görkem Açar, Istanbul Gelisim University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07865819
- Sponsor's protocol ID
- TUTAR-HSEP-2025-01
- Status last verified
- Oct 2026
- First submitted
- 3 Oct 2026
- Last updated
- 8 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 8 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Chronic Effect of a Hamstring-Specific Exercise Protocol on Athletic Performance Indicators in Amateur and Professional Soccer Players: A Randomized Controlled Trial
- ClinicalTrials.gov ID
- NCT07865819
- Acronym / sponsor ID
- TUTAR-HSEP-2025-01
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 144 participants (actual)
- Lead sponsor
- Istanbul Gelisim UniversityUniversity, hospital or other
- Study start
- 14 May 2025 (actual)
- Primary completion
- 6 Aug 2025 (actual)
- Study completion
- 6 Aug 2025 (actual)
- First posted
- 8 Oct 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 randomized controlled trial aimed to investigate the effects of a 12-week hamstring-specific exercise protocol (HSEP) on athletic performance in professional and amateur male soccer players.
A total of 144 soccer players participated in the study, including 72 professional and 72 amateur players. Participants were randomly assigned to four groups: professional training (n = 36), professional control (n = 36), amateur training (n = 36), and amateur control (n = 36).
The intervention groups performed a structured hamstring-specific exercise protocol consisting of three bodyweight exercises: the Diver, Glider, and Single-Leg Hip Bridge. The program was implemented twice weekly for 12 weeks alongside regular soccer training. Training volume was progressively increased throughout the intervention period. The control groups continued their usual soccer training without performing the additional hamstring-specific exercise protocol.
Athletic performance was assessed before and after the intervention using vertical jump and countermovement jump tests, the 30-15 Intermittent Fitness Test, one-repetition maximum squat and deadlift tests, eccentric hamstring strength measurements, and maximal sprint velocity assessments.
The primary purpose of this study was to determine whether adding a structured hamstring strengthening program to regular soccer training improves physical performance and whether professional and amateur soccer players respond differently to the intervention.
The findings may help physiotherapists, sports scientists, and strength and conditioning coaches better understand the role of hamstring-specific training in soccer performance.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| Professional Training Group | Experimental | Behavioral: Hamstring-Specific Exercise Protocol (HSEP)Professional male soccer players (n = 36) performed a 12-week hamstring-specific exercise protocol (HSEP) twice weekly in addition to their regular soccer training. The intervention consisted of three bodyweight exercises: Diver, Glider, and Single-Leg Hip Bridge. Training volume was progressively increased throughout the intervention period. |
| Professional Control Group | No intervention | –Professional male soccer players (n = 36) continued their regular soccer training and competitive match participation for 12 weeks without receiving the additional hamstring-specific exercise protocol. |
| Amateur Training Group | Experimental | Behavioral: Hamstring-Specific Exercise Protocol (HSEP)Amateur male soccer players (n = 36) performed a 12-week hamstring-specific exercise protocol (HSEP) twice weekly in addition to their regular soccer training. The intervention consisted of three bodyweight exercises: Diver, Glider, and Single-Leg Hip Bridge. Training volume was progressively increased throughout the intervention period. |
| Amateur Control Group | No intervention | –Amateur male soccer players (n = 36) continued their regular soccer training and competitive match participation for 12 weeks without receiving the additional hamstring-specific exercise protocol. |
Who may qualify
- Ages
- 18 to 40 years
- Sex
- Male only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- Male soccer players actively competing at a licensed professional or amateur level.
- Regular participation in soccer training (4-5 sessions per week) during the competitive season.
- No previous participation in a structured hamstring strengthening program. Being free from injury at the time of enrollment. Provision of written informed consent before participation.
Key exclusion criteria (2 listed)
- Presence of an injury at the time of enrollment. Previous participation in a structured hamstring strengthening program. Not meeting the required licensed professional or amateur soccer participation criteria.
- Declining to provide written informed consent.
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 |
|---|---|---|
| Hamstring-Specific Exercise Protocol (HSEP)The hamstring-specific exercise protocol (HSEP) consisted of three bodyweight exercises: Diver, Glider, and Single-Leg Hip Bridge. The intervention was performed twice weekly for 12 consecutive weeks during the competitive season, in addition to regular soccer training. Each session began with a 10-minute general and dynamic warm-up. Training volume was progressively increased, with 3 sets of 12 repetitions during weeks 1-4, 3 sets of 16 repetitions during weeks 5-8, and 3 sets of 20 repetitions during weeks 9-12. All exercises were supervised by athletic performance coaches, with a supervision ratio of one coach per four players. The control groups continued their regular soccer training without receiving the additional HSEP intervention. | Behavioural | Amateur Training Group, Professional Training Group |
Primary outcome
Change in Maximal Sprint Velocity
Time frame: Baseline and Week 12 (Post-intervention)
Maximal linear sprint velocity was assessed during a 60-meter maximal sprint test using a 10 Hz GPS device (Catapult Vector S7, Catapult Sports, Australia). Each participant completed two trials, and the highest recorded velocity (km/h) was used for analysis. Changes in maximal sprint velocity were determined by comparing baseline and post-intervention measurements.
9 secondary outcomes
Change in Countermovement Jump Height
Time frame: Baseline and Week 12 (Post-intervention)
Change in Vertical Jump Height
Time frame: Baseline and Week 12 (Post-intervention)
Change in Estimated Maximal Oxygen Uptake (VO2max)
Time frame: Baseline and Week 12 (Post-intervention)
Change in Final Velocity During the 30-15 Intermittent Fitness Test
Time frame: Baseline and Week 12 (Post-intervention)
Change in Total Distance Covered During the 30-15 Intermittent Fitness Test
Time frame: Baseline and Week 12 (Post-intervention)
Change in Squat One-Repetition Maximum Strength
Time frame: Baseline and Week 12 (Post-intervention)
Change in Deadlift One-Repetition Maximum Strength
Time frame: Baseline and Week 12 (Post-intervention)
Change in Right-Leg Maximal Eccentric Hamstring Force
Time frame: Baseline and Week 12 (Post-intervention)
Change in Left-Leg Maximal Eccentric Hamstring Force
Time frame: Baseline and Week 12 (Post-intervention)
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 8 Oct 2026.
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.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Hamstring-Specific Exercise Protocol (HSEP) in people with Athletic Performance Copy and Hamstring Muscle Strength Copy, run by Istanbul Gelisim University 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 3 inclusion and 2 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 8 Oct 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?
Change in Maximal Sprint Velocity (time frame: Baseline and Week 12 (Post-intervention)). 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 8 Oct 2026.