Sports-related concussions — media, science and policy

Journal name:
Nature Reviews Neurology
Year published:
Published online


Although growing awareness about the potential long-term deleterious effects of sport-related concussion has led to increased attention to the risks of collision sports, calls to ban these sports, such as American football, might be premature. Collision sports have a relatively high incidence of concussions, but participation in these sports also confers a host of benefits. In addition, the associated risks of participation, including concussion, have not been definitively shown to outweigh the benefits they provide, and the risk–benefit ratio might vary among individuals. The risks of concussion and repetitive concussions associated with collision sports are unknown in the general population and not well characterized even in elite athlete populations. In this article, we discuss current knowledge on sports-related concussion, its neurological consequences, and implications for regulation of the practice of collision sports.

At a glance


  1. From concussion to CTE [mdash] sequence of events and knowledge gaps.
    Figure 1: From concussion to CTE — sequence of events and knowledge gaps.

    Data from clinical case series and animal models suggest that athletes who sustain concussions could develop a form of tauopathy, chronic traumatic encephalopathy (CTE), which leads to the deposition of fibrillary insoluble proteins and progressive deterioration of brain function. A definitive causal link between concussion and CTE has yet to be established, however.

  2. Rates of concussions linked to main collision sports in student athletes.
    Figure 2: Rates of concussions linked to main collision sports in student athletes.

    The rate of concussions (25 sports) and recurrent concussions (17 sports) per 10,000 exposures was measured by the National Collegiate Athletic Association Injury Surveillance Program from 2009–2010 to 2013–2014 in student athletes, during practice and competition. Adapted with permission from SAGE Publications Ltd © Zuckerman, S. L. et al. Am. J. Sports. Med. 43, 26542662 (2015).


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Author information


  1. Rebekah Mannix is in the Division of Emergency Medicine, 300 Longwood Avenue, Boston, Massachusetts 02115, USA.

  2. William P. Meehan is in the Division of Sports Medicine at the Boston Children's Hospital, 300 Longwood Avenue, Boston, Massachusetts 02115, USA.

    • William P. Meehan III
  3. Alvaro Pascual-Leone is in the Division of Cognitive Neurology at the Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, Massachusetts 02115, USA.


All authors researched data for article, discussed its content, and wrote and edited the article before submission.

Competing interests statement

R.M. and W.P.M.'s research is supported by funding from the National Hockey League Alumni Association through the Corey C. Griffin Pro-Am Tournament. The work of W.P.M., A.P.-L. and R.M. is supported by the Football Players Health Study at Harvard University. W.P.M. receives royalties from ABC-Clio publishing for the sale of his book Kids, Sports, and Concussion: A Guide for Coaches and Parents, and royalties from Wolters Kluwer for working as an author for UpToDate. He is under contract with ABC-Clio publishing for a future book entitled Concussions, and with Springer International Publishing for a future book entitled Head and Neck Injuries in Young Athletes. The content of this article is solely the responsibility of the authors and does not necessarily represent the official views of Harvard Catalyst, Harvard University and its affiliated academic health-care centres, the NIH, the Sidney R. Baer, Jr. Foundation, or the National Football League Players Association.

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Author details

  • Rebekah Mannix

    Rebekah Mannix is a staff physician in emergency medicine at Boston Children's Hospital, Massachusetts, USA, where she also serves as Co-Director of the Brain Injury Center. She is an Assistant Professor of Paediatrics and Emergency Medicine at Harvard Medical School in Boston. She conducts both clinical and preclinical traumatic brain injury and pediatric trauma research.

  • William P. Meehan III

    William P. Meehan III is Director of the Micheli Center for Sports Injury Prevention, Director of Research for the Brain Injury Center at Boston Children's Hospital, Massachusetts, USA, and Co-Director of The Football Players Health Study at Harvard University in Boston. He graduated from Harvard Medical School where he is currently an Assistant Professor of Paediatrics and Orthopaedics. He conducts both clinical and scientific research in the area of sports injuries and concussive brain injury.

  • Alvaro Pascual-Leone

    Alvaro Pascual-Leone is Professor of Neurology and an Associate Dean for Clinical and Translational Research at Harvard Medical School, Boston, Massachussetts, USA. He serves as Chief for the Division of Cognitive Neurology and the Director of the Berenson-Allen Center for Noninvasive Brain Stimulation at Beth Israel Deaconess Medical Center in Boston. Pascual-Leone's research aims at understanding the mechanisms that control brain plasticity in order to identify new therapeutic interventions to treat cognitive impairment and dementia.

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