Proceedings of a Workshop

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This activity was partially supported by contract 75D30121D11240, Task 75D30124F00045 between the National Academy of Sciences and the Centers for Disease Control and Prevention and support to the Forum on Traumatic Brain injury from the Department of Defense (contract W81XWH22C0033); Department of Veterans Affairs (contract 36C24E22P0005); National Highway Traffic Safety Administration; National Institute on Disability, Independent Living, and Rehabilitation Research (contract 140D0423C0099 through the Department of the Interior); AARP; Abbott Laboratories; American Academy of Neurology; American Academy of Physical Medicine and Rehabilitation; American Association of Neurological Surgeons; American College of Surgeons; American Occupational Therapy Association; American Physical Therapy Association; Brain Injury Association of America; Cohen Veterans Bioscience; Concussion Legacy Foundation; Emergency Nurses Association; National Association of Emergency Medical Technicians; National Association of State Head Injury Administrators; National Collegiate Athletic Association; National Neurotrauma Society; and Toyota Motor North America. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.

International Standard Book Number-13: 978-0-309-99568-9
Digital Object Identifier: https://doi.org/10.17226/29227

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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2026. Exploring risks of repeated head impacts in youth and strategies to minimize exposure: Proceedings of a workshop. Washington, DC: The National Academies Press. https://doi.org/10.17226/29227.

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WORKSHOP PLANNING COMMITTEE¹

FREDERICK P. RIVARA (Chair), University of Washington

MICHAEL ALOSCO, Boston University

KRISTY ARBOGAST, Children’s Hospital of Philadelphia

JEFFREY J. BAZARIAN, University of Rochester Medical Center

JACLYN CACCESE, The Ohio State University

AVINASH CHANDRAN, Datalys Center

GERARD GIOIA, Children’s National Hospital

CHRISTOPHER GIZA, University of California, Los Angeles

TAMERAH HUNT, Georgia Southern University

REBEKAH MANNIX, Boston Children’s Hospital

LUCA MARINELLI, GE HealthCare Technology & Innovation Center

CHRISTINA MASTER, University of Pennsylvania Perelman School of Medicine and Children’s Hospital of Philadelphia

KEITH YEATES, University of Calgary, Alberta

Staff

CHANEL MATNEY, Workshop Director and Program Officer (until March 2025)

KATHERINE BOWMAN, Director, Forum on Traumatic Brain Injury

REBEKAH HUTTON, Senior Program Officer, Board on Children, Youth, and Families

EMILY PACKARD DAWSON, Program Officer (from August 2025)

ASHLEY BOLOGNA, Research Assistant (from June 2025)

GAYATRI SOMAIYA, Senior Program Assistant (until June 2025)

CLARE STROUD, Senior Director, Board on Health Sciences Policy

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¹ The National Academies of Sciences, Engineering, and Medicine’s planning committees are solely responsible for organizing the workshop, identifying topics, and choosing speakers. The responsibility for the published Proceedings of a Workshop rests with the workshop rapporteurs and the institution.

FORUM ON TRAUMATIC BRAIN INJURY¹

DONALD BERWICK (Cochair), Institute for Healthcare Improvement

CORINNE PEEK-ASA (Cochair), University of California, San Diego

JOE BONNER, Eunice Kennedy Shriver National Institute of Child Health and Human Development

JOE BRENNAN, Avalon Action Alliance

JAVIER CÁRDENAS, West Virginia University and American Academy of Neurology

JOHN CORRIGAN, The Ohio State University and Brain Injury Association of America

RAMON DIAZ-ARRASTIA, University of Pennsylvania Perelman School of Medicine

LAGWYN DURDEN, National Collegiate Athletic Association

COURTNEY EDWARDS, Parkland Health and Emergency Nurses Association

E. WESLEY ELY, Vanderbilt University Medical Center

BRUCE EVANS, Upper Pine River Fire Protection District and National Association of Emergency Medical Technicians

STEVEN FLANAGAN, New York University Grossman School of Medicine and American Academy of Physical Medicine and Rehabilitation

DAVID GOLDSTEIN, George Washington University

GENE GURKOFF, University of California, Davis, and National Neurotrauma Society

ODETTE HARRIS, Stanford University School of Medicine and VA Palo Alto Health Care System

MAGALI HAAS, Cohen Veterans Bioscience

STUART HOFFMAN, Department of Veterans Affairs

RICHARD HODES, National Institute on Aging

FREDERICK KORLEY, University of Michigan

WALTER KOROSHETZ, National Institute of Neurological Disorders and Stroke

RACHEL LAZARUS, AARP

KATHY LEE, Department of War

JULIE MALLOY, American Occupational Therapy Association

TARA JO MANAL, American Physical Therapy Association

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¹ The National Academies of Sciences, Engineering, and Medicine’s forums and roundtables do not issue, review, or approve individual documents. The responsibility for the published Proceedings of a Workshop rests with the workshop rapporteurs and the institution.

GEOFFREY MANLEY, University of California, San Francisco, and Zuckerberg San Francisco General Hospital

LUCA MARINELLI, GE HealthCare Technology & Innovation Center

CHRISTINA L. MASTER, University of Pennsylvania Perelman School of Medicine and Children’s Hospital of Philadelphia

BETH MCQUISTON, Abbott Laboratories

CATE MILLER, National Institute on Disability, Independent Living, and Rehabilitation Research

CANDICE NASH, Toyota Motor North America

CHRIS NOWINSKI, Concussion Legacy Foundation

TESSIE OCTOBER, Eunice Kennedy Shriver National Institute of Child Health and Human Development

DAVID OKONKWO, University of Pittsburgh School of Medicine

TOLULOPE O. OYESANYA, Duke University School of Nursing

MAYUR B. PATEL, Vanderbilt University Medical Center and American College of Surgeons Committee on Trauma

LESLIE PRICHEP, BrainScope Company, Inc.

TERRY RAUCH, Department of War

JOEL SCHOLTEN, Department of Veterans Affairs

SHELLY TIMMONS, Medical College of Wisconsin and American Association of Neurological Surgeons

GAMUNU WIJETUNGE, National Highway Traffic Safety Administration

REBECCAH WOLFKIEL, National Association of State Head Injury Administrators

KRISTINE YAFFE, University of California, San Francisco

Forum Staff

KATHERINE BOWMAN, Forum Director

ASHLEY BOLOGNA, Research Assistant

CHRISTIE BELL, Finance Business Partner

CLARE STROUD, Senior Program Director, Biomedical and Health Sciences

James C. Puffer, M.D./American Board of Family Medicine Fellowship

ANITA RAVI, PurpLE Health Foundation

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Reviewers

This Proceedings of a Workshop was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published proceedings as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the charge. The review comments and draft manuscript remain confidential to protect the integrity of the process.

We thank the following individuals for their review of this proceedings:

Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the content of the proceedings nor did they see the final draft before its release. The review of this proceedings was overseen by JAMES PERRIN, Harvard Medical School. He was responsible for making certain that an independent examination of this proceedings was carried out in accordance with standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the rapporteurs and the National Academies.

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Contents

Overview

1 Introduction

Family and Community Perspectives Around Youth Activities and Repetitive Head Impact Risks

References

2 Characterizing Repeated Head Impacts in Youth

Defining and Measuring RHI Exposure in Youth

Describing RHI Exposure in Youth

References

3 Exploring the Evidence on Health Outcomes of Youth Exposure to Repetitive Head Impacts

Assessing Short-Term Outcomes of RHI Exposure in Youth

Assessing Long-Term Outcomes of RHI Exposure in Youth

Discussing Factors that May Influence Outcomes After RHI

References

4 Examining Strategies to Address Repeated Head Impact Exposure in Youth

Exploring Interventions to Minimize Exposure to RHI

Engaging Communities and Families to Reduce RHI Exposure

References

5 Reflecting on Research Gaps and Opportunities for Youth Exposure to Repetitive Head Impacts

Reflections on Research Gaps and Opportunities

Final Remarks

References

Appendixes

A Statement of Task

B Workshop Agenda

C Planning Committee and Speaker Biographies

Boxes, Figures, and Table

BOXES

1-1 Family Perspectives on Navigating Youth Sports Decision Making: A Conversation with Khalilah Mays

1-2 Family Perspectives on Navigating Youth Sports Decision Making: A Conversation with Katie Culver

1-3 Family Perspectives on Navigating Youth Sports Decision Making: A Conversation with Amy Jo Riggs, Xavier Deckard, and Olyana Deckard

FIGURES

2-1 Reported concussion thresholds across studies

2-2 Context on differential exposure to repeated head impacts

2-3 Percentage of male and female participants by sports categories in studies included in a systematic review of sensor acceleration event monitoring research for youth sports

4-1 Outline of steps to codesign the COACH program and implementation plan to reduce head impacts in youth football

4-2 Schematic of Valued Action, a web-based shared decision-making intervention tailored to postconcussion return-to-sport decisions for youth athletes

5-1 Historical contrasts between radiation and head impact exposures

TABLE

3-1 Select One-Season Studies of Youth Repetitive Head Impact Exposure and Outcomes