BDNFTOUCH-BDNFNCT07395765
Comparing Touch-Limited and Free-Play 4v4 Small-Sided Games (SSGs)
A study testing SSGf and SSGr in people with BDNF and Small Side Game, run by Aksaray University Training and Research Hospital at 1 site in Turkey (Türkiye).
Trial summary
This study aimed to compare acute serum BDNF and cognitive performance following touch-limited versus free-play 4v4 small-sided games (SSGs) in male soccer players. This randomized crossover controlled trial aimed to examine the acute effects of touch-limited (SSGr) vs free-play (SSGf) 4v4 SSGs on serum brain-derived… Read more about this study
- Who is it for?
- Ages 18 to 25 years, men onlyHealthy volunteers can take part
- Conditions the study is for
- BDNF, Small Side Game, Football Players
- What is being tested?
- SSGf and SSGr
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 32 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 23 Jul 2025to 12 Sep 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 25 years
- Men only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Semi-professional male soccer players with ≥10 years of soccer experience
- Aged between 18 and 25 years
- No known medical condition that prevents participation in exercise
- No recent use of medications or supplements that could enhance anaerobic or aerobic performance
- No recent severe lower-extremity injury (>12 months)
Who cannot join
- Experiencing any discomfort before, during, or after exercise
- History of alcohol or substance addiction
- Any other condition or factor that may prevent full participation in the study protocol
- Being a goalkeeper
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Acute Serum Brain-Derived Neurotrophic Factor (BDNF) and Executive Function Responses to Touch-Limited vs Free-Play 4v4 Small-Sided Games in Male Soccer Players
This study aimed to compare acute serum BDNF and cognitive performance following touch-limited versus free-play 4v4 small-sided games (SSGs) in male soccer players.
This randomized crossover controlled trial aimed to examine the acute effects of touch-limited (SSGr) vs free-play (SSGf) 4v4 SSGs on serum brain-derived neurotrophic factor (BDNF), blood lactate levels and executive function performance in male soccer players. All participants completed the two conditions in a randomized and counterbalanced manner. To ensure balanced exposure, they were assigned to one of two groups (n=16), each following a distinct condition. A seven-day interval separated each session to reduce residual physiological or cognitive effects. The trial protocol was developed in line with Consolidated Standards of Reporting Trials guidelines, including for within-subject designs and non-pharmacological interventions. Participants were blinded to the study hypothesis.
Read more
Teams were formed based on the coach's assessment of the players' technical, tactical, and physical abilities. To minimize differences in player's maximum oxygen consumption (VO2 max) level estimated from the 30-15 Intermittent Fitness Test (30-15 IFT) were also taken into account.
The SSG sessions were conducted at 10.00-12.00 to have similar chronobiological characteristics on a natural grass pitch during the off-season period under the supervision of A-licenced coaches to ensure consistency and adherence to protocol. All players continued their routine off-season training program, which involved three training sessions (strength, aerobic activity, aerobic running) per week. Players were advised to avoid strenuous exercise within 48 h, be prohibited from drinking alcohol or coffee within 24 h, and have at least 7-8 h of sleep before the intervention. During this study, the players were instructed to maintain their dietary habits and general lifestyle.
During the first visit, participants' resting heart rate was recorded. Then body weight and body fat percentage were assessed using bioelectrical impedance analysis. To mitigate potential learning effects, all participants underwent a familiarization session with Stroop Test. Finally, participants performed 30-15 IFT to determine aerobic capacity, and peak heart rate.
During the two subsequent visits, each participant completed both SSGr and SSGf sessions, with one session (SSGr or SSGf) completed during visit 2 and the other during visit 3. The half of the participants completed SSGr first and the other half completed the SSGf first.
Blood samples were collected and cognitive performance tests were conducted before and after each training session. The heart rate was monitored throughout each session. Additionally, following each exercise session, rating scale mental effort scores were used to assess the players' psychophysiological responses. Water intake was permitted during all the recovery periods throughout the training sessions.
Each exercise session began with a standardized 10-minute warm-up, including light jogging, dynamic stretching, and soccer-specific movement preparation drills with and without the ball. All exercise sessions lasted 40 minutes in total, consisting of a 10-minute standardized warm-up, 24 minutes of exercise, and a 5-minute recovery period.
In this study, we conducted 4v4 SSG to foster environments recommended by studies suggesting that game formats with fewer players may offer a more cognitively demanding structure, including creativity, exploratory behaviors, and decision-making challenges for players. The SSGs with mini-goals were played on a 30 × 24 m pitch (720 m²), with dimensions set to provide a comparable relative area per player (90 m²). The duration of the SSG was carefully standardized, consisting of four 4 min bouts with 3 min passive recovery intervals between bouts. During recovery, players went to the sideline for ad libitum rehydration and returned to their positions in walking speed. These movements were excluded from analysis as they are not representative of match play. Across all experimental conditions, participants were encouraged to maximize the number of goals scored to foster a competitive environment and sustain a high level of effort. Players were instructed to exert maximal effort during gameplay and received verbal encouragement, which excluded feedback on their technical and tactical performance. To ensure uninterrupted play and maximize effective playing time, multiple balls were placed along the sidelines, and two coaches stationed around the field promptly provided replacement balls when required. The SSGf was free-flowing without imposed constraints, such as touch limitations, mandatory passing, or predefined scoring conditions. In the SSGr, the only difference from the free-play condition was limiting the number of ball touches. Accordingly, each time players received the ball, they were required to release it by the second touch at the latest.
- Conditions
- BDNF, Small Side Game, Football Players
- Being tested
- SSGf, SSGr
- Keywords
- BDNF, Lactate, Cognitive Performance, SSG
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
SSGfBehavioural
Also called Small Sided Games Free
The SSGf was free-flowing without imposed constraints, such as touch limitations, mandatory passing, or predefined scoring conditions.
SSGrBehavioural
Also called Small Sided Games Rules
The only difference from the free-play condition was limiting the number of ball touches. Accordingly, each time players received the ball, they were required to release it by the second touch at the latest (e.g., via a pass or shot). In the event of a violation of this two-touch rule (i.e., >2 touches), possession was immediately awarded to the opposing team to preserve the continuity of play.
| Study group | Role | What they receive |
|---|---|---|
| SSGf | Experimental | Not described Receives: Behavioral: SSGf |
| SSGr | Experimental | Not described Receives: Behavioral: SSGr |
What is being measured
The primary outcome is the main question the study is designed to answer.
BDNF
BDNF levels were measured using a Sunred Brand Enzyme-Linked İmmunosorbent Assay (ELISA) kit from blood samples taken baseline and after exercise, and the results were reported in ng/mL units.
Measured: • Baseline, Immediately After Exercise (Day 1)
Lactate
Lactate levels were measured in millimoles per liter (mmol/L) from capillary/venous blood samples taken before and after exercise using a lactate analyzer.
Measured: • Baseline, Immediately After Exercise (Day 1)
Stroop Test
The Stroop Test is a widely used neuropsychological assessment tool to evaluate selective attention, inhibitory control, processing speed, and executive function under cognitive interference.
The Congruent condition measures baseline color-naming speed by requiring participants to respond to stimuli in which the color word matches the ink color. Completion time (or reaction time) and errors were recorded.
The Incongruent condition measures inhibitory control and interference resolution by requiring participants to name the ink color while ignoring a conflicting color word. Completion time (or reaction time) and errors were recorded.
Performance was evaluated using (i) condition-specific completion/reaction times and error counts and (ii) the Stroop interference score, calculated as the difference between conditions (Incongruent - Congruent) for time (and/or errors). Lower interference values reflect better inhibitory control and interference resolution, whereas higher va
Measured: • Baseline, immediately after exercise (Day 1)
Rating Scale Mental Effort
RSME (Rating Scale Mental Effort) is a single-item measure scored on a 0-150 continuum. Immediately after each session, participants indicate their perceived mental effort by marking a 150-mm visual analogue line anchored with verbal descriptors; the distance from the origin is measured in millimeters and recorded as the RSME score (0-150). Higher scores reflect greater perceived mental effort (i.e., a higher cognitive/mental demand imposed by the session).
Measured: • Immediately After Exercise (Day 1)
Feeling Scale
The Feeling Scale (FS) is a single-item measure used to assess affective valence during exercise and is scored on an 11-point scale ranging from -5 to +5. Participants select the value that best reflects how they feel at a given time point (e.g., during or immediately after exercise), where -5 indicates "very bad," 0 represents a neutral feeling, and +5 indicates "very good." Higher scores denote more positive affective responses, whereas lower scores reflect more negative affective states.
Measured: • Baseline, Immediately After Exercise (Day 1),
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Feb 2026
- Study start23 Jul 2025
- Primary completion28 Aug 2025
- Study completion12 Sep 2025
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 BDNFStudies 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
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 32 participants (actual)
Sponsor and investigators
- Lead sponsor
- Aksaray University Training and Research Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, serkan pancar, Aksaray University Training and Research Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07395765
- Sponsor's protocol ID
- 21.13
- Acronym
- TOUCH-BDNF
- Status last verified
- Feb 2026
- First submitted
- 1 Feb 2026
- Last updated
- 10 Feb 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data will not be shared due to confidentiality concerns arising from the small sample size and the collection of sensitive biomarker and performance-related measures. The combination of these variables increases the risk of participant re-identification through data triangulation, even after anonymization. To protect participant privacy and ensure compliance with ethical approval and data protection regulations, individual-level data will therefore not be made publicly available. Only aggregated results are reported.
Publications
Birinci YZ, Pancar S, Soylu Y, Sarandol E, Simsek H, Sahin S, Rumpf MC. Touch Restriction Versus Free-Play Small-Sided Games in Soccer: Acute Effects on Serum BDNF, Executive Function, and Technical Actions. Eur J Sport Sci. 2026 Sep;26(9):e70242. doi: 10.1002/ejsc.70242.
PubMed 42632905
Study at a glance
From the registry record, last updated by the sponsor on 10 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Acute Serum Brain-Derived Neurotrophic Factor (BDNF) and Executive Function Responses to Touch-Limited vs Free-Play 4v4 Small-Sided Games in Male Soccer Players
- ClinicalTrials.gov ID
- NCT07395765
- Acronym / sponsor ID
- TOUCH-BDNF / 21.13
- Conditions
- BDNF, Small Side Game, Football Players
- Keywords
- BDNF, Lactate, Cognitive Performance, SSG
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 32 participants (actual)
- Lead sponsor
- Aksaray University Training and Research HospitalUniversity, hospital or other
- Study start
- 23 Jul 2025 (actual)
- Primary completion
- 28 Aug 2025 (actual)
- Study completion
- 12 Sep 2025 (actual)
- First posted
- 9 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.
This study aimed to compare acute serum BDNF and cognitive performance following touch-limited versus free-play 4v4 small-sided games (SSGs) in male soccer players.
This randomized crossover controlled trial aimed to examine the acute effects of touch-limited (SSGr) vs free-play (SSGf) 4v4 SSGs on serum brain-derived neurotrophic factor (BDNF), blood lactate levels and executive function performance in male soccer players. All participants completed the two conditions in a randomized and counterbalanced manner. To ensure balanced exposure, they were assigned to one of two groups (n=16), each following a distinct condition. A seven-day interval separated each session to reduce residual physiological or cognitive effects. The trial protocol was developed in line with Consolidated Standards of Reporting Trials guidelines, including for within-subject designs and non-pharmacological interventions. Participants were blinded to the study hypothesis.
Teams were formed based on the coach's assessment of the players' technical, tactical, and physical abilities. To minimize differences in player's maximum oxygen consumption (VO2 max) level estimated from the 30-15 Intermittent Fitness Test (30-15 IFT) were also taken into account.
The SSG sessions were conducted at 10.00-12.00 to have similar chronobiological characteristics on a natural grass pitch during the off-season period under the supervision of A-licenced coaches to ensure consistency and adherence to protocol. All players continued their routine off-season training program, which involved three training sessions (strength, aerobic activity, aerobic running) per week. Players were advised to avoid strenuous exercise within 48 h, be prohibited from drinking alcohol or coffee within 24 h, and have at least 7-8 h of sleep before the intervention. During this study, the players were instructed to maintain their dietary habits and general lifestyle.
During the first visit, participants' resting heart rate was recorded. Then body weight and body fat percentage were assessed using bioelectrical impedance analysis. To mitigate potential learning effects, all participants underwent a familiarization session with Stroop Test. Finally, participants performed 30-15 IFT to determine aerobic capacity, and peak heart rate.
During the two subsequent visits, each participant completed both SSGr and SSGf sessions, with one session (SSGr or SSGf) completed during visit 2 and the other during visit 3. The half of the participants completed SSGr first and the other half completed the SSGf first.
Blood samples were collected and cognitive performance tests were conducted before and after each training session. The heart rate was monitored throughout each session. Additionally, following each exercise session, rating scale mental effort scores were used to assess the players' psychophysiological responses. Water intake was permitted during all the recovery periods throughout the training sessions.
Each exercise session began with a standardized 10-minute warm-up, including light jogging, dynamic stretching, and soccer-specific movement preparation drills with and without the ball. All exercise sessions lasted 40 minutes in total, consisting of a 10-minute standardized warm-up, 24 minutes of exercise, and a 5-minute recovery period.
In this study, we conducted 4v4 SSG to foster environments recommended by studies suggesting that game formats with fewer players may offer a more cognitively demanding structure, including creativity, exploratory behaviors, and decision-making challenges for players. The SSGs with mini-goals were played on a 30 × 24 m pitch (720 m²), with dimensions set to provide a comparable relative area per player (90 m²). The duration of the SSG was carefully standardized, consisting of four 4 min bouts with 3 min passive recovery intervals between bouts. During recovery, players went to the sideline for ad libitum rehydration and returned to their positions in walking speed. These movements were excluded from analysis as they are not representative of match play. Across all experimental conditions, participants were encouraged to maximize the number of goals scored to foster a competitive environment and sustain a high level of effort. Players were instructed to exert maximal effort during gameplay and received verbal encouragement, which excluded feedback on their technical and tactical performance. To ensure uninterrupted play and maximize effective playing time, multiple balls were placed along the sidelines, and two coaches stationed around the field promptly provided replacement balls when required. The SSGf was free-flowing without imposed constraints, such as touch limitations, mandatory passing, or predefined scoring conditions. In the SSGr, the only difference from the free-play condition was limiting the number of ball touches. Accordingly, each time players received the ball, they were required to release it by the second touch at the latest.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| SSGf | Experimental | Behavioral: SSGf |
| SSGr | Experimental | Behavioral: SSGr |
Who may qualify
- Ages
- 18 to 25 years
- Sex
- Male only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Semi-professional male soccer players with ≥10 years of soccer experience
- Aged between 18 and 25 years
- No known medical condition that prevents participation in exercise
- No recent use of medications or supplements that could enhance anaerobic or aerobic performance
- No recent severe lower-extremity injury (>12 months)
Key exclusion criteria (4 listed)
- Experiencing any discomfort before, during, or after exercise
- History of alcohol or substance addiction
- Any other condition or factor that may prevent full participation in the study protocol
- Being a goalkeeper
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 |
|---|---|---|
| SSGfAlso: Small Sided Games FreeThe SSGf was free-flowing without imposed constraints, such as touch limitations, mandatory passing, or predefined scoring conditions. | Behavioural | SSGf |
| SSGrAlso: Small Sided Games RulesThe only difference from the free-play condition was limiting the number of ball touches. Accordingly, each time players received the ball, they were required to release it by the second touch at the latest (e.g., via a pass or shot). In the event of a violation of this two-touch rule (i.e., >2 touches), possession was immediately awarded to the opposing team to preserve the continuity of play. | Behavioural | SSGr |
Primary outcome
BDNF
Time frame: • Baseline, Immediately After Exercise (Day 1)
BDNF levels were measured using a Sunred Brand Enzyme-Linked İmmunosorbent Assay (ELISA) kit from blood samples taken baseline and after exercise, and the results were reported in ng/mL units.
Lactate
Time frame: • Baseline, Immediately After Exercise (Day 1)
Lactate levels were measured in millimoles per liter (mmol/L) from capillary/venous blood samples taken before and after exercise using a lactate analyzer.
Stroop Test
Time frame: • Baseline, immediately after exercise (Day 1)
The Stroop Test is a widely used neuropsychological assessment tool to evaluate selective attention, inhibitory control, processing speed, and executive function under cognitive interference. The Congruent condition measures baseline color-naming speed by requiring participants to respond to stimuli in which the color word matches the ink color. Completion time (or reaction time) and errors were recorded. The Incongruent condition measures inhibitory control and interference resolution by requiring participants to name the ink color while ignoring a conflicting color word. Completion time (or reaction time) and errors were recorded. Performance was evaluated using (i) condition-specific completion/reaction times and error counts and (ii) the Stroop interference score, calculated as the difference between conditions (Incongruent - Congruent) for time (and/or errors). Lower interference values reflect better inhibitory control and interference resolution, whereas higher va
Rating Scale Mental Effort
Time frame: • Immediately After Exercise (Day 1)
RSME (Rating Scale Mental Effort) is a single-item measure scored on a 0-150 continuum. Immediately after each session, participants indicate their perceived mental effort by marking a 150-mm visual analogue line anchored with verbal descriptors; the distance from the origin is measured in millimeters and recorded as the RSME score (0-150). Higher scores reflect greater perceived mental effort (i.e., a higher cognitive/mental demand imposed by the session).
Feeling Scale
Time frame: • Baseline, Immediately After Exercise (Day 1),
The Feeling Scale (FS) is a single-item measure used to assess affective valence during exercise and is scored on an 11-point scale ranging from -5 to +5. Participants select the value that best reflects how they feel at a given time point (e.g., during or immediately after exercise), where -5 indicates "very bad," 0 represents a neutral feeling, and +5 indicates "very good." Higher scores denote more positive affective responses, whereas lower scores reflect more negative affective states.
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 10 Feb 2026.
- Derived from this study: PubMed 42632905Birinci YZ, Pancar S, Soylu Y, Sarandol E, Simsek H, Sahin S, Rumpf MC. Touch Restriction Versus Free-Play Small-Sided Games in Soccer: Acute Effects on Serum BDNF, Executive Function, and Technical Actions. Eur J Sport Sci. 2026 Sep;26(9):e70242. doi: 10.1002/ejsc.70242.
- Individual participant dataSharing planned: No. Individual participant data will not be shared due to confidentiality concerns arising from the small sample size and the collection of sensitive biomarker and performance-related measures. The combination of these variables increases the risk of participant re-identification through data triangulation, even after anonymization. To protect participant privacy and ensure compliance with ethical approval and data protection regulations, individual-level data will therefore not be made publicly available. Only aggregated results are reported.
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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.
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 SSGf and SSGr in people with BDNF and Small Side Game, run by Aksaray University Training and Research Hospital 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 4 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 10 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?
BDNF (time frame: • Baseline, Immediately After Exercise (Day 1)). The study lists 5 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 NCT07395765, 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 10 Feb 2026.