Interval Effects for Concussion Prevention

Overseen By Blair Johnson, PhD

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: Indiana University

Disqualifiers: Recent head injury, Eye diseases, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 24

Duration: 4 weeks

102 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial examines how different time intervals between head impacts affect brain health in soccer players. It compares short and long intervals between sessions of heading a soccer ball to determine which better prevents concussion-related issues. Ideal participants are current soccer players with at least five years of heading experience and no recent head injuries. As an unphased trial, this study provides participants the chance to contribute to important research that could enhance safety guidelines in soccer.

Do I need to stop my current medications for the trial?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial team or your doctor.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that heading a soccer ball can be done safely with certain precautions. Using lightweight soccer balls reduces risks during practice, making it safer for players. One study found that limiting headers in youth soccer led to fewer concussions, dropping to just 6% over a few years.

Research has examined how heading affects learning and brain function over short periods. Some studies suggest there might be short-term effects, but these vary. Training and proper technique are important in reducing risks.

Overall, the safety of heading depends on factors like the type of ball and the frequency of heading. These studies suggest that with the right precautions, heading can be a safe activity. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it explores new ways to prevent concussions in soccer players by varying the timing of impacts. Unlike standard care, which often focuses on protective gear or rest after injury, this trial investigates whether changing the interval between heading sessions might reduce concussion risk. By comparing short and long intervals between soccer headings, researchers hope to uncover insights into how the timing of repeated impacts affects brain health. This could lead to new guidelines for safer sports practices, potentially benefiting athletes worldwide.

What evidence suggests that this trial's treatments could be effective for concussion prevention?

This trial compares the effects of different intervals between soccer headings on brain health. Participants in the "Long Interval" group will perform headings with 72 hours between sessions, while those in the "Short Interval" group will have 24 hours between sessions. Studies have shown mixed results about the effects of heading a soccer ball on brain health. For the "Long Interval" group, one study found that heading the ball does not harm brain function, and another found fewer soccer-related concussions when headers were limited. However, for the "Short Interval" group, research shows worse brain performance with frequent heading. Both approaches aim to understand how the time between head impacts might affect the brain, with some evidence suggesting potential risks with short intervals. More research is needed to fully understand the effects. ^{2 3 6 7 8}

Who Is on the Research Team?

Keisuke Kawata, PhD

Principal Investigator

Indiana University Bloomington Department of Kineseology

Are You a Good Fit for This Trial?

This trial is for current soccer players with at least 5 years of experience in heading the ball. They must be able to consent without a representative. Those who've had recent head injuries or eye conditions like glaucoma that could affect study results can't participate.

Inclusion Criteria

Current soccer player (intercollegiate, club, intramural, recreational)

At least 5 years of soccer heading experience

Ability to provide informed consent without a legally authorized representative (LAR)

Exclusion Criteria

Any head, neck, or face injury within the 6 months prior to enrollment, including concussions, that precludes participation in contact sports

Determination that the participant is unsuitable for study entry or potentially unable to complete all aspects of the study based on the judgement of the Investigator

I have an eye condition affecting my eye's blood vessels.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo repetitive head impacts with varying intervals (24 hours or 72 hours) over 4 weeks

4 weeks

Twice per week

Follow-up

Participants are monitored for changes in blood biomarkers, retinal and ocular-motor health, and EEG signals

2 weeks

Baseline, 24 hours after final session, 14 days after final session

What Are the Treatments Tested in This Trial?

Interventions

• Long Interval
• Short Interval

Trial Overview The study aims to understand how different time intervals between repetitive subconcussive head impacts influence brain health in military service members, using short and long intervals as variables.

How Is the Trial Designed?

Group I: Short Interval - heading Experimental Treatment 1 Intervention

Participants in the heading group will undergo 16 soccer headings, twice per week, with 24 hours in between each session.

Group II: Long Interval - heading Experimental Treatment 1 Intervention

Participants in the heading group will undergo 16 soccer headings, twice per week, with 72 hours in between each session.

Group III: Short Interval - kicking Placebo Group 1 Intervention

Participants in the kicking-control group will undergo 16 soccer kicking, twice per week, with 24 hours in between each session.

Group IV: Long Interval - kicking Placebo Group 1 Intervention

Participants in the kicking-control group will undergo 16 soccer kicking, twice per week, with 72 hours in between each session.

Who Is Running the Clinical Trial?

Indiana University

Lead Sponsor

Trials

1,063

Recruited

1,182,000+

United States Department of Defense

Collaborator

Trials

940

Recruited

339,000+

University of Rochester

Collaborator

Trials

883

Recruited

555,000+

University at Buffalo

Collaborator

Trials

139

Recruited

105,000+

Boston Children's Hospital

Collaborator

Trials

801

Recruited

5,584,000+

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC11678946/

Youth Soccer Heading Exposure and Its Effects on Clinical ... The results from the current study point to there being no detrimental relationship between heading exposure and neurocognitive functioning. This finding is ...

2. nature.com nature.com/articles/s41598-024-52163-8

Individualized monitoring of longitudinal heading exposure ... Here we conducted a comprehensive heading exposure analysis across all players on a university women's soccer team for over two calendar years.

3. aaos.org aaos.org/aaosnow/2025/june/research/research08/

Policy Restricting Headers in Youth Soccer Shows ... The research team identified a 25.6 percent relative risk reduction in soccer-related concussions as a percentage of all soccer-related injuries ...

4. sciencedirect.com sciencedirect.com/science/article/pii/S0887617702001518

Soccer heading frequency predicts neuropsychological ... This study investigated the presence of neuropsychological deficits associated with hitting the ball with one's head (heading) during soccer play.

5. aaos-annualmeeting-presskit.org aaos-annualmeeting-presskit.org/2025/research-news/header-restriction-policy-in-youth-soccer-shows-promising-impact-on-concussion-rates/

Header Restriction Policy in Youth Soccer Shows Promising ... The research team identified a 25.6% relative risk reduction in soccer-related concussions as a percentage of all soccer-related injuries ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10499164/

Quantitative Analysis of Ball-Head Impact Exposure in ... The Get aHEAD Safely in Soccer program recommends using lightweight soccer balls for practicing heading so that players can train in a lower-risk setting; ...

7. journals.plos.org journals.plos.org/plosone/article?id=10.1371/journal.pone.0329329

Effects of repetitive head impacts from a single season on the ... Repetitive head impact exposure by position was associated with significant decreases in absolute error (p < 0.001), increases in peak velocity (p < 0.001), and ...

8. chop.edu chop.edu/news/chop-researchers-comprehensively-assess-safety-using-your-head-youth-soccer

CHOP Researchers Comprehensively Assess the Safety ... This lab-based study simulated these limits conducting 10 repeated soccer headers within a single session with experienced teenage players.