Exploring Risks of Repeated Head Impacts in Youth and Strategies to Minimize Exposure: Proceedings of a Workshop (2026)
Chapter: 1 Introduction
1
Introduction
Key Points Highlighted by Individual Speakers1
- The workshop examined exposure to repeated head impacts in youth under 18, exploring definitions and measurement methods, connections to subsequent health outcomes, interventions to reduce head impact exposures or mitigate risks, and lived experiences with repetitive head impacts and concussions and return-to-activity decision making. It also discussed major open questions and key areas where further research remains needed (Rivara, Yeates).
- Reducing repeated head impacts in youth is a broadly supported health goal. Progress is aided by the development of evidence-based interventions, the translation of knowledge into policy and practice, and collaborative efforts among families, educators, coaches, health care providers, and researchers (Yeates).
- Families navigating the issue of exposure to repetitive head impacts and concussions seek clear, accessible, and practical guidance to recognize concerning symptoms, make informed return-to-play decisions, and adapt participation when needed (Culver, Mays, Riggs).
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1 This list is the rapporteurs’ summary of points made by the individual speakers identified, and the statements have not been endorsed or verified by the National Academies of Sciences, Engineering, and Medicine. They are not intended to reflect a consensus among workshop participants.
- Balancing awareness of repetitive head impact risks with the benefits of sports participation requires individualized decisions, openness to reevaluation, collaborative youth involvement, and honest concussion symptom reporting, supported by coaches, parents, and medical professionals. While risk cannot be eliminated, it can be reduced through proper technique, appropriate protective equipment, policy changes, and adherence to safety protocols (Culver, Master, Riggs, Warren).
- Preventing and managing repeated head impacts requires an approach that accounts for the grey area between head impacts that lead to diagnosed concussion and head impacts that do not lead to diagnosed concussions, ensuring that decisions consider health, developmental, and social consequences and benefits of participation in sports activities (Master).
- Education and communication are essential for mitigating injury risk across contact and noncontact sports. Efforts should focus on teaching athletes, families, coaches, school personnel, and sporting organizations to recognize symptoms, apply safe techniques, use protective equipment correctly, and maintain open dialogue to support prevention, early identification, and management of head impacts and concussions (Keyes, Master, Warren).
- Partnerships between health care providers and schools are needed. Having accessible, digestible information helps school staff support students during recovery from concussion and reduces anxiety about academic effects after concussions (Keyes).
- Implementing protocols to reduce youth exposure to head impacts and identify concussions is feasible even in settings where resources are limited, by using free tools, symptom checklists, and community-based education (Keyes, Master, Warren).
- More research is needed on the effects of potential sources of RHI beyond contact sports, such as chronic violence exposure on youth (Keyes), on noncontact sports with growing rates of inadvertent head impacts (Warren), and through large-scale pediatric studies to close gaps in understanding and inform prevention strategies (Master).
The National Academies of Sciences, Engineering, and Medicine hosted a virtual public workshop April 15–16, 2025, to explore what is currently known and unknown about health outcomes related to youth exposure to repeated head impacts (RHI), examine who is at greatest risk of exposure to such impacts, and consider effective strategies to reduce that risk. This Proceedings of a Workshop highlights key points made by workshop participants during the presentations and panel discussions.2 See Appendixes A and B for the workshop statement of task and agenda and Appendix C for biographies of planning committee members and speakers.
Frederick Rivara, the Seattle Children’s Guild Association Endowed Chair in Pediatric Research, vice-chair and professor of pediatrics, and adjunct professor of epidemiology at the University of Washington and chair of the workshop planning committee, and Keith Yeates, professor of psychology, pediatrics, and neurosciences at the University of Calgary, Alberta, opened the workshop by introducing its focus and the areas it would cover. A concussion is a form of mild traumatic brain injury (TBI) that can follow a head impact and produce clinical signs and symptoms such as headache, nausea, or problems with balance or memory. By contrast, Rivara emphasized that many more youth experience head impacts that do not lead to a diagnosed concussion; these head impacts can occur during sports activities, such as routine collisions in contact sports or heading the ball, and can also arise in nonsport contexts. The workshop was motivated by the need to better understand whether exposure to this type of repeated head impacts in youth under age 18 produces measurable biological changes and results in short- or long-term health consequences. For this reason, Rivara explained that the workshop aimed to focus particularly on the broader phenomenon of repeated, nonconcussive head impacts (e.g., head impacts that do not meet clinical criteria for concussion; some studies also call these subconcussive impacts). A consensus definition for RHI does not yet exist, he noted, and definitions and measurement approaches have varied across studies. To serve the workshop’s purpose, the RHI definition proposed by Arbogast (see Chapter 2) and the focus of epidemiological and clinical evidence discussed during the workshop particularly emphasized the effects of exposure to RHI that did not result in diagnosed concussions.
Rivara emphasized that the workshop sought to ground presentations and discussions in available scientific evidence and that the workshop’s varied range of speakers and perspectives was intended to ensure a rich dialogue, noting the significance of understanding RHI for families, educators, medical providers, and researchers, as well as the importance of accurate information to guide decision making. The workshop sought to focus on
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2 ChatGPT was used to assist in drafting content summarizing speakers’ recorded presentations and remarks in this proceedings, drawing only from the workshop transcript. All material generated by an AI platform used in this document was fact checked to ensure accuracy of the presented information.
what is known about exposures that take place during youth and not on head impacts experienced by collegiate or professional athletes, Rivara continued. Recognizing, however, that a greater number of studies have been carried out in older adolescents and adults in various civilian and military occupations, speakers were encouraged to be clear about the extent and limitations of available evidence in those under age 18 and where extrapolations were being drawn from other studied populations.
Yeates emphasized that disentangling the effects of repeated, nonconcussive head impacts from those of repeated concussions is challenging but will be essential for clear communication and policy. In practice, many families engage with the care system after their child has experienced a diagnosed injury such as a concussion, and make return-to-learning and return-to-activity decisions in that context. Because of this fact, some workshop discussions incorporate concussion-related research and insights when focusing on family experiences and shared decisions, for example around whether to start or continue activities with higher RHI exposure after a youth athlete has already experienced a diagnosed injury.
Yeates also highlighted the ongoing scientific and public debate about links between repeated concussions and other types of repeated head impacts and development of chronic traumatic encephalopathy (CTE),3 with publications sometimes reaching differing conclusions (Fortington et al., 2025; Nowinski et al., 2022). Scientific and popular discourse in this area is often polarized, he said (Anderson et al., 2023; Associated Press, 2019; Barr, 2020; Hoge, 2018; Randolph, 2018), and he argued that a balanced, evidence-based approach is needed. The workshop, he said, offered an opportunity to step back and clarify what is known, what remains unknown, and what policies and practices are needed to protect youth worldwide.
The workshop thus sought to advance several goals, Rivara and Yeates outlined: to clarify the state of knowledge regarding RHI in youth; to identify critical research gaps; and to provide actionable information to parents, teachers, coaches, and others to reduce risk while preserving the benefits of physical activity. The 2-day agenda included nine sessions. Sessions on the first day addressed the definition and measurement of RHI, including moving beyond imprecise proxy measures toward more accurate tools, as well
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3 “CTE is a brain disease that affects how the brain works. It is linked to a build-up of abnormal proteins that damage brain tissue and cause brain cells to undergo cell death. Research suggests CTE is associated with long-term exposure to repeated hits to the head (head impacts). There is no strong evidence that shows that getting one or more concussions (or other mild traumatic brain injuries) or occasional hits to the head leads to CTE…. Scientists are not certain what symptoms are directly linked to CTE…. Currently, the only way doctors can confirm a CTE diagnosis is by checking the brain of a person after they die.” See https://www.cdc.gov/traumatic-brain-injury/about/repeated-head-impacts.html (accessed September 4, 2025).
as identifying the populations exposed to RHI and which youth are most at risk. Subsequent sessions explored short-term (weeks to months) and long-term (6–12 months or more) health consequences from RHI and examined biological and social factors that may modify the experienced health effects.
Sessions during the second day explored strategies to minimize youth exposure to RHI or mitigate its negative consequences, from policy and rule changes—such as restrictions on body checking to reduce impacts—to modifications in equipment, playing techniques, or training regimens. Discussions also explored frameworks guiding how families, health care providers, sports organizations, and schools can collaborate in responding to a concussion or in weighing the implications of future RHI exposure after an injury. The final sessions turned to research priorities, including refining measurement methods, exploring understudied health outcomes, and applying insights from other public health challenges. Yeates underscored that while much remains to be learned, the collective commitment to youth health and safety provides a strong foundation for advancing research, policy, and practice in this field. Reducing repeated head impacts in youth is an important and achievable public health goal with broad agreement, he concluded (Cantu et al., 2025).
FAMILY AND COMMUNITY PERSPECTIVES AROUND YOUTH ACTIVITIES AND REPETITIVE HEAD IMPACT RISKS
To help ground the workshop in real-world relevance, recorded conversations and a panel discussion explored the lived experiences of several families navigating issues related to youth head impact exposure and the decision-making processes that occur in partnership with health care providers, coaches, and schools. The objectives were threefold: to share perspectives from families, to explore questions that arise when managing care and determining readiness to return to learning or sports in the context of youth injuries, and to examine how different families have approached the relative risks and benefits of recreational activities that may expose youth to RHI. Although by no means the only circumstance in which families encounter RHI, participation in youth sports activities is a common situation around which many families engage with this decision making. Three such families’ experiences with sports and head impact exposures are shared in Boxes 1-1, 1-2, and 1-3.
Panel: Community Awareness, Approaches to Decision Making, and Research Needs
A moderated discussion drew from these insights and explored how families can effectively partner with professionals and institutions to address
BOX 1-1
Family Perspectives on Navigating Youth Sports Decision Making: A Conversation with Khalilah Mays
Christina Master, a pediatric/adolescent sports medicine physician at the Children’s Hospital of Philadelphia and professor of pediatrics and orthopedic surgery at the University of Pennsylvania Perlman School of Medicine, welcomed a conversation with parent Khalilah Mays that explored her family’s experience with sports and decisions surrounding repetitive head impacts. Mays shared that her 12-year-old son, Aaron, enjoys playing football, appreciating its structure and camaraderie. However, midway through his second season playing, he sustained a concussion. Master asked about the family’s approach to returning to sport after the injury and their decision making about the potential for head impacts associated with contact/collision sports. Mays explained that Master’s guidance about delaying tackle football until after age 14 helped facilitate a constructive conversation with Aaron, allowing him to feel ownership over a decision to switch to flag football until high school. This approach made the transition feel collaborative rather than imposed, Mays said, and opened space for reevaluation in the future based on Aaron’s health. Aaron is currently thriving, Mays continued, recently finishing basketball season and now taking part in baseball season.
Master praised Aaron’s thoughtfulness and maturity, and invited Mays to share what questions she hopes future research on sports and head impacts might answer. Mays voiced concern about the long-term implications of her son sustaining a concussion at a young age and emphasized the uncertainty she faces as a parent trying to monitor his well-being. She finds herself asking how he feels after practices or games, wondering whether he may have bumped his head. What she wants research to enable creating, she explained, is a practical, expert-informed checklist of symptoms or warning signs, including those not necessarily tied to a concussion, that can help parents determine when to consult a health care provider for further evaluation. This is especially important in community leagues, Mays continued, where medical personnel may be limited and coaching is typically volunteer based, leaving parents with less structured support than in formal school athletic programs. Mays emphasized that having clear, accessible guidance would ease the burden on families and reduce the feeling of having to “wing it” when it comes to protecting their children’s health.
BOX 1-2
Family Perspectives on Navigating Youth Sports Decision Making: A Conversation with Katie Culver
Christina Master opened a conversation by welcoming Katie Culver, a learning specialist with the School District of Philadelphia and a parent of multisport youth athletes, and asked about her children’s sports involvement. Culver described her three children’s participation in soccer, basketball, and lacrosse—along with past involvement in volleyball and swimming—and noted that athletics are deeply rooted in her family, as both she and her husband are former college athletes. Drawing on her graduate school research on barriers to sports participation for low-income girls, Culver emphasized the benefits of sports for all children while noting that research on concussion prevalence had informed her thinking on concerns related to contact and collision sports. She explained that although football was a family tradition on her husband’s side, both parents agreed that their children would not play the sport competitively. She also reflected on her concerns about head impacts in soccer, especially from heading the ball, and in lacrosse, where rules and equipment vary by gender.
Master noted that Culver’s children attend a school partnered with the Minds Matter Concussion Program at the Children’s Hospital of Philadelphia in research on repetitive head impacts, including an upcoming study in lacrosse, and asked what questions she hoped researchers would address. Culver said she is interested in how to advance prevention, including the role of helmet technology, the differing helmet requirements for boys’ and girls’ sports, and the potential for other strategies—such as exercises—that could reduce head injury risk, especially in sports without helmets. She shared that two of her children had experienced diagnosed concussions—one in basketball and one in soccer—and expressed interest in the role of sex hormones in head impact risk and recovery. While recognizing the importance of safety, Culver also emphasized the value of allowing children to enjoy a variety of sports, noting that parents cannot prevent every risk. She highlighted the importance of coaches who are supportive of players and families, avoid pressuring children to play when they should not, and encourage young athletes to be informed and listen to their bodies. She also underscored the need for guidance and resources that help support thoughtful, appropriate decision making about participation. She added that seeing a specialist after her daughter’s injury provided clear evidence and guidance that deepened her understanding and enabled her to be more supportive in recovery through appropriate rest, heightened awareness of re-injury risk, and attentive monitoring.
BOX 1-3
Family Perspectives on Navigating Youth Sports Decision Making: A Conversation with Amy Jo Riggs, Xavier Deckard, and Olyana Deckard
Tamerah Hunt, an associate professor at Georgia Southern University, invited Amy Jo Riggs, a professor of health sciences and kinesiology and a mom, to reflect on her family’s decision-making process around sports participation by her children, Xavier and Olyana Deckard. Riggs recalled being surprised when Xavier, entering ninth grade, wanted to play tackle football. They were initially hesitant owing to safety concerns, and Xavier Deckard described how he persuaded his parents to consider letting him play by creating a presentation to show he had carefully thought through the decision. He explained that his parents’ primary concern was protecting him from the long-term effects of concussions, especially given his academic goals and plans for college. Xavier compared managing football risks to safe driving—acknowledging that while risk cannot be eliminated, it can be reduced through consistent safety measures such as wearing proper equipment, using correct tackling techniques, and following best practices to protect his head. Xavier added that awareness of potential head impacts makes him more attentive to safety practices and to his coaches’ guidance.
Hunt invited Olyana Deckard to share her experiences, and she spoke about moving from gymnastics to soccer in eighth grade, quickly developing a passion for the sport. She also took up volleyball and continued her long-standing love of dance. During soccer, Olyana sustained two concussions within 6 weeks, ending her season. The family decided not to make a permanent decision about the sport without allowing her time to recover and gain more experience in her role as a goalkeeper. Riggs said her discussion with the athletic director about safety measures and position-specific coaching for the next season eased some of her stress, though uncertainty after her daughter’s concussions caused anxiety. Both Amy Jo Riggs and Olyana Deckard emphasized taking the recovery process from concussions seriously, avoiding rushing back, and reporting symptoms openly—echoing advice from the team’s athletic trainer on the importance of players’ willingness to share their symptoms and not withhold them out of a desire to keep playing.
Reflecting on broader lessons, Riggs noted that whether to allow a child to play a sport with potential head injury risks is highly personal, and her foremost concern as a parent is the potential for injury that could sideline her child. Still, she believes that sports provide important benefits, citing the confidence, teamwork, time management, and drive they foster, and noting that her children’s strong academic performance is partly fueled by their commitment to their teams. While being aware of the risk of head impact exposure, she felt the family had been able to make informed decisions. However, she noted that if her children were to experience more severe symptoms—such as loss of consciousness, neurological impairment, or additional concussions—it could prompt the family to reconsider and potentially end their participation in that activity.
information about RHI, return-to-play and return-to-learn decisions after concussions, and practice or policy changes that protect youth health. Tamerah Hunt, Georgia Southern University, led a panel conversation featuring Christina Master, professor of pediatrics and orthopedic surgery at the University of Pennsylvania Perelman School of Medicine and pediatric/adolescent primary care sports medicine specialist at the Children’s Hospital of Philadelphia and codirector of the Minds Matter Concussion Program; Karlita Warren, athletic trainer and founder of The Kizo Effect, LLC, who collaborates with Washington, DC, schools on sports-related health issues; and Laura Keyes, social worker with the Minds Matter Concussion Program at the Children’s Hospital of Philadelphia.
Balancing Risks and Benefits Through a Nuanced Approach
Master urged a nuanced approach—using a “scalpel” rather than a “sledgehammer”—when weighing the potential risks and benefits of activities that involve exposure to head impacts. She described a continuum of head impacts from minor impacts to diagnosed concussions and the challenges in measurement and classification. For example, multiple smaller impacts may collectively lead to symptoms, and some head or body impacts may cause brief symptoms without meeting the criteria for concussion. Sharing a patient story, she raised questions about how to classify brief or mild symptom episodes after impacts, which may not rise to the diagnosis of concussion, and how to weigh risks when definitions are still evolving.
Master refers to these cases as potentially “neurologically notable events” when speaking with families, underscoring the challenge in defining what counts as clinically significant. Until better diagnostic tools exist, she advised that decisions consider both uncertainties as well as the physical, social, and developmental benefits of sports. Keyes agreed, highlighting that families need safe spaces to discuss concerns openly. Warren added that in some communities, athletic trainers may be the only health care providers youth see, making open discussion, awareness, and risk mitigation critical.
Building an Aware Community
Everyone involved, including athletes, parents, coaches, schools, and organizations, needs to know how to spot possible concussions, play safely, and talk openly about any hits to the head, the panelists said. Warren emphasized education on risks, safe playing techniques, proper and consistent equipment use, and to teach youth athletes to recognize symptoms indicative of a potential concussion and to report even subtle symptoms related to head impacts, to prepare them to seek help if symptoms appear later. She works with coaches to reduce unnecessary contact and holds preseason
information sessions on injury prevention and healthy lifestyle habits that can support recovery. Keyes emphasized educating school administrators and educators to improve return-to-learn and return-to-activity processes, and Master added that youth themselves must be empowered to notice and report concussion symptoms. She illustrated this with an anecdote in which she asked her own son whether he had headaches after hockey practice, underscoring that children may not realize certain symptoms are not “normal” and should be shared. A “concussion aware” community, the panelists agreed, shares responsibility for early recognition and timely care addressing exposures and possible concussions, to ensure that symptoms are addressed early, speed recovery, and reduce the potential for cumulative health and social effects.
Best Practices in the Context of Available Resources
Responding to an audience question about how practices vary from school to school (e.g., baseline testing, information meetings, protocols for taking students out of games), Master emphasized that high-quality practices can be more easily implemented in settings with greater resources, but are needed and can be implemented across all settings, including those with fewer resources. She referenced recent research that suggests using normative measures may be more effective than preinjury baselines for diagnosing and managing concussion (Crane et al., 2023). Athletic trainers and coaches can use free tools such as the Sport Concussion Assessment Tool 6 (SCAT6, 2023) or symptom checklists to guide evaluation in the absence of computerized systems, Warren noted. Keyes underscored the importance of clear, accessible education materials for families and staff that can be applied to their settings in real time without specialized training. The panelists agreed that education, simple assessment tools, and adherence to best practices can improve recognition and management in all resource settings.
Supporting Schools in the Return-to-Learn Process
Keyes discussed her work with schools and educators to help students recover academically after experiencing concussions. She explained that while schools want to “do no harm,” this sometimes leads to anxiety and overly cautious approaches that may delay a student’s reintegration into learning. She emphasized flexible, collaborative approaches that combine clinical insight with educators’ knowledge of the student. Master added that families sometimes seek advice on whether RHI exposure explains a change in academic performance. She explained that multiple factors, including mental health, learning differences, and attention issues, can intersect with
RHI exposure and recommended addressing any existing symptoms regardless of their cause, to ensure effective support.
Grounding Conversations and Research Needs
Master encouraged framing clinical discussions with families in both realism and optimism to validate challenges while emphasizing available treatments for a young person’s symptoms such as anxiety, depression, attention-deficit/hyperactivity disorder, or visual or vestibular problems. The goal is informed decision making without excessive fear and to focus on actionable steps that support recovery from concussion and safe participation in activities going forward, she said. Warren called for greater research on head impacts in noncontact sports where inadvertent impacts are becoming more common, as well as strategies to reduce long-term effects from RHI exposure. Keyes highlighted the need to study another source of RHI in youth—exposure to chronic violence. Master emphasized the need for greater research on children across TBI research broadly, noting the lack of large-scale, multicenter studies focusing specifically on long-term pediatric outcomes. Despite current measurement challenges and knowledge gaps, all three speakers emphasized that protecting young athletes requires targeted education, consistent communication, and building informed, engaged communities.
The experiences and insights shared by the families and panelists helped provide a foundation for exploring the existing evidence base and research opportunities related to RHI described in subsequent chapters.
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