title: Head Impact Biomechanics in Women's College Soccer.
abstract: There are limited nonlaboratory soccer head impact biomechanics data. This is surprising given soccer's global popularity. Epidemiological data suggest that female college soccer players are at a greater concussion injury risk than their male counterparts. Therefore, the purposes of our study were to quantify head impact frequency and magnitude during women's soccer practices and games in the National Collegiate Athletic Association and to characterize these data across event type, playing position, year on the team, and segment of game (first and second halves).
  
  
  
  Head impact biomechanics were collected from female college soccer players (n = 22; mean ± SD age = 19.1 ± 0.1 yr, height = 168.0 ± 3.5 cm, mass = 63.7 ± 6.0 kg). We employed a helmetless head impact measurement device (X2 Biosystems xPatch) before each competition and practice across a single season. Peak linear and rotational accelerations were categorized based on impact magnitude and subsequently analyzed using appropriate nonparametric analyses.
  
  
  
  Overall, women's college soccer players experience approximately seven impacts per 90 min of game play. The overwhelming majority (~90%) of all head impacts were categorized into our mildest linear acceleration impact classification (10g-20g). Interestingly, a higher percentage of practice impacts in the 20g-40g range compared with games (11% vs 7%) was observed.
  
  
  
  Head impact biomechanics studies have provided valuable insights into understanding collision sports and for informing evidence-based rule and policy changes. These have included changing the football kickoff, ice hockey body checking ages, and head-to-head hits in both sports. Given soccer's global popularity, and the growing public concern for the potential long-term neurological implications of collision and contact sports, studying soccer has the potential to impact many athletes and the sports medicine professionals caring for them.
authors.affiliation: 1Matthew Gfeller Sport-Related Traumatic Brain Injury Research Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, Chapel Hill, NC; 2Human Movement Science Curriculum, Department of Allied Health Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, NC; 3Department of Kinesiology, Towson University, Towson, MD; and 4Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, Chapel Hill, NC.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Lynall
authors.forename: Michael D
authors.initials: MD
authors.lastname: Clark
authors.forename: Erin E
authors.initials: EE
authors.lastname: Grand
authors.forename: Jaclyn C
authors.initials: JC
authors.lastname: Stucker
authors.forename: Ashley C
authors.initials: AC
authors.lastname: Littleton
authors.forename: Alain J
authors.initials: AJ
authors.lastname: Aguilar
authors.forename: Meredith A
authors.initials: MA
authors.lastname: Petschauer
authors.forename: Elizabeth F
authors.initials: EF
authors.lastname: Teel
authors.forename: Jason P
authors.initials: JP
authors.lastname: Mihalik
mesh_terms: D000054:Acceleration; D056352:Athletes; D001265:Athletic Injuries / Q000503:physiopathology*; D001696:Biomechanical Phenomena; D001924:Brain Concussion / Q000503:physiopathology*; D005260:Female; D006257:Head / Q000503:physiopathology; D006801:Humans; D011446:Prospective Studies; D012916:Soccer / Q000293:injuries*; D014495:Universities; D055815:Young Adult