football concussion

Head Impact Exposure Common in Youth Football Practice Interview with:

Mireille E. Kelley Ph.D. Staff Consultant for Engineering Systems Inc.

Dr. Kelley

Mireille E. Kelley Ph.D.
Staff Consultant for Engineering Systems Inc. What is the background for this study?

Response: Youth and high school football players can sustain hundreds of head impacts in a season and while most of these impacts do not result in any signs or symptoms of concussion, there is concern that these repetitive subconcussive impacts may have a negative effect on the brain.

The results of this study are part of an NIH-funded study to understand the effects of subconcussive head impact exposure on imaging data collected at pre- and post-season time points. The present study leveraged the longitudinal data that was collected in the parent study to understand how head impact exposure changes among athletes from season to season and how that relates to changes measured from imaging. What are the main findings?

Response: The main findings for this study include that while there are general trends of increasing head impact exposure (HIE) with age and level of play in football, head impact exposure (HIE) varies among individual athletes from season to season and there are likely not consistent increases in HIE from one year to the next among youth football players. For example, some youth football players experienced greater number of head impacts in their second year of play than in their first, while other youth players experienced fewer number of head impacts their second year of play compared to their first.

Additionally, the results from this study demonstrated that there were both increases and decreases in brain imaging metrics derived from diffusion tensor imaging (DTI) from the first season to the second season and those changes were significantly positively correlated with several head impact exposure metrics. In particular, DTI changes were associated with changes in the number of practice impacts over the entire season and the median number of impacts per practice session. What should readers take away from your report?

Response: The results from this study support continued efforts to reduce the number and frequency of head impacts in football, especially during practice sessions. What recommendations do you have for future research as a result of this work?

Response: Future investigations should continue to evaluate the long-term relationship between head impact exposure and neuroimaging findings to improve our understanding of how HIE may affect the brain over many seasons of participation in contact sports. Additionally, future efforts should seek to develop evidence-based strategies and practical solutions to reduce HIE in football.


Head Impact Exposure in Youth Football: Comparing Age- and Weight-Based Levels of Play

Mireille E. Kelley, Jillian E. Urban, Logan E. Miller, Derek A. Jones, Mark A. Espeland, Elizabeth M. Davenport, Christopher T. Whitlow, Joseph A. Maldjian, and Joel D. Stitzel

Journal of Neurotrauma 2017 34:11, 1939-1947 is not a forum for the exchange of personal medical information, advice or the promotion of self-destructive behavior (e.g., eating disorders, suicide). While you may freely discuss your troubles, you should not look to the Website for information or advice on such topics. Instead, we recommend that you talk in person with a trusted medical professional.

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Last Updated on July 1, 2021 by Marie Benz MD FAAD