Brian D Stemper1,2,3, Alok S Shah2,3, Jason P Mihalik4, Jaroslaw Harezlak5, Steven Rowson6, Stefan Duma6, Larry D Riggen5, Alison Brooks7, Kenneth L Cameron8, Christopher C Giza9, Joshua Goldman9, Megan N Houston8, Jonathan Jackson10, Gerald McGinty10, Steven P Broglio11, Thomas W McAllister12, Michael McCrea2,3. 1. Joint Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, WI. 2. Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI. 3. Neuroscience Research, Zablocki Veterans Affairs Medical Center, Milwaukee, WI. 4. Matthew Gfeller Sport-Related Traumatic Brain Injury Center, University of North Carolina at Chapel Hill, Chapel Hill, NC. 5. Indiana University School of Public Health, Department of Epidemiology and Biostatistics, Bloomington, IN. 6. Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA. 7. Department of Orthopedics, School of Medicine and Public Health, University of Wisconsin, Madision, WI. 8. John A. Feagin Jr. Sports Medicine Fellowship, Keller Army Hospital, United States Military Academy, West Point, NY. 9. Departments of Neurosurgery and Pediatrics, UCLA Steve Tisch BrainSPORT Program, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA. 10. Department of Sports Medicine, United States Air Force Academy, Colorado Springs, CO. 11. Michigan Concussion Center, University of Michigan, Ann Arbor, MI. 12. Department of Psychiatry, Indiana School of Medicine, Indianapolis, IN.
Abstract
INTRODUCTION: Regulatory efforts toward reducing concussion risk have begun to focus on decreasing the number of head impacts (i.e., head impact burden) sustained by athletes in contact sports. To that end, in 2018, the NCAA decreased the number of preseason on-field team activities for Division I teams from 29 to 25. The objective of the current study was to quantify changes in practice schedule and head impact exposure between the 2017 and 2018 football preseasons. METHODS: Athletes from five NCAA Division I football teams (n = 426) were consented and enrolled. RESULTS: On average, athletes participated in 10% fewer contact practices in 2018. However, the effect of this ruling on preseason head impact burden was mixed. Across all athletes, the total preseason head impact burden was essentially the same from 2017 to 2018. However, this study revealed significant team-by-team differences in preseason head impact burden, with one team demonstrating a 35% increase in the average number of recorded head impacts from 2017 to 2018, despite a modest decrease in the number of contact practices. Other teams had similar or decreased head impact burden. CONCLUSIONS: Team-based differences in total preseason head impact burden were attributable to changes in daily practice schedule, with longer practice durations and more intense contact practice sessions contributing to increases in daily head impact exposure that, in turn, led to greater preseason head impact burden. Results of this study have highlighted the difficulty in decreasing contact sport head impact exposure through rule changes targeted at limiting on-field team activities. Future efforts aimed specifically at contact practice duration, daily head impact exposure, or limiting time in specific drills may be more effective at reducing total preseason head impact burden.
INTRODUCTION: Regulatory efforts toward reducing concussion risk have begun to focus on decreasing the number of head impacts (i.e., head impact burden) sustained by athletes in contact sports. To that end, in 2018, the NCAA decreased the number of preseason on-field team activities for Division I teams from 29 to 25. The objective of the current study was to quantify changes in practice schedule and head impact exposure between the 2017 and 2018 football preseasons. METHODS: Athletes from five NCAA Division I football teams (n = 426) were consented and enrolled. RESULTS: On average, athletes participated in 10% fewer contact practices in 2018. However, the effect of this ruling on preseason head impact burden was mixed. Across all athletes, the total preseason head impact burden was essentially the same from 2017 to 2018. However, this study revealed significant team-by-team differences in preseason head impact burden, with one team demonstrating a 35% increase in the average number of recorded head impacts from 2017 to 2018, despite a modest decrease in the number of contact practices. Other teams had similar or decreased head impact burden. CONCLUSIONS: Team-based differences in total preseason head impact burden were attributable to changes in daily practice schedule, with longer practice durations and more intense contact practice sessions contributing to increases in daily head impact exposure that, in turn, led to greater preseason head impact burden. Results of this study have highlighted the difficulty in decreasing contact sport head impact exposure through rule changes targeted at limiting on-field team activities. Future efforts aimed specifically at contact practice duration, daily head impact exposure, or limiting time in specific drills may be more effective at reducing total preseason head impact burden.
Authors: Jason P Mihalik; Avinash Chandran; Jacob R Powell; Patricia R Roby; Kevin M Guskiewicz; Brian D Stemper; Alok S Shah; Steven Rowson; Stefan Duma; Jaroslaw Harezlak; Larry Riggen; Steven P Broglio; Thomas W McAllister; Michael McCrea Journal: Ann Biomed Eng Date: 2020-11-02 Impact factor: 3.934
Authors: Jack Seifert; Alok S Shah; Jaroslaw Harezlak; Steven Rowson; Jason P Mihalik; Larry Riggen; Stefan Duma; Alison Brooks; Kenneth L Cameron; Christopher C Giza; Joshua Goldman; Kevin M Guskiewicz; Megan N Houston; Jonathan C Jackson; Gerald McGinty; Paul Pasquina; Steven P Broglio; Thomas W McAllister; Michael A McCrea; Brian D Stemper Journal: Ann Biomed Eng Date: 2022-08-06 Impact factor: 4.219
Authors: Steve Rowson; Jason Mihalik; Jillian Urban; Julianne Schmidt; Steve Marshall; Jaroslaw Harezlak; Brian D Stemper; Mike McCrea; Jim Funk Journal: Ann Biomed Eng Date: 2022-10-17 Impact factor: 4.219
Authors: Kyle K Obana; John D Mueller; Bryan M Saltzman; Thomas S Bottiglieri; Christopher S Ahmad; Robert L Parisien; David P Trofa Journal: Orthop J Sports Med Date: 2021-10-15
Authors: Brian D Stemper; Alok Shah; Rachel Chiariello; Cassandra McCarthy; Kristin Jessen; Bailey Sarka; Jack Seifert; Matthew D Budde; Kevin Wang; Christopher M Olsen; Michael McCrea Journal: Front Behav Neurosci Date: 2022-03-09 Impact factor: 3.558
Authors: Alyssa Phelps; Michael L Alosco; Zachary Baucom; Kaitlin Hartlage; Joseph N Palmisano; Jennifer Weuve; Jesse Mez; Yorghos Tripodis; Robert A Stern Journal: JAMA Netw Open Date: 2022-04-01
Authors: Melissa S DiFabio; Daniel R Smith; Katherine M Breedlove; Thomas A Buckley; Curtis L Johnson Journal: Brain Behav Date: 2022-05-27 Impact factor: 3.405
Authors: Bradley J Lauck; Aaron M Sinnott; Adam W Kiefer; Darin A Padua; Jacob R Powell; Haley R Sledge; Jason P Mihalik Journal: Ann Biomed Eng Date: 2022-08-16 Impact factor: 4.219