title: Physical collisions and injury in professional rugby league match-play.
abstract: OBJECTIVE
  To document the frequency of physical collisions and incidence of contact injury in professional rugby league match-play.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  Video recordings of 77 National Rugby League (NRL) matches were coded for the number and type of physical collisions in which players were involved. Each match was analysed and coded for defensive (i.e. tackles, missed tackles, and ineffective tackles) and attacking collisions (i.e. tackled in possession, broken tackles, offloads, support runs, and decoy runs). Injuries that occurred as a result of a physical collision were also recorded.
  
  
  RESULTS
  The total number of physical collisions performed per game was greatest in the wide running forwards (47 [95% CI, 42-52]), and was significantly greater (P<0.05) than the hit-up forwards (36 [95% CI, 32-40]), adjustables (29 [95% CI, 26-32]), and outside backs (24 [95% CI, 22-27]) positional groups. A total of 48 collision injuries were sustained, resulting in an overall injury incidence of 10.6 (95% CI, 7.6-13.6) per 10,000 collisions. Injuries resulting from attacking collisions were consistently higher than injuries sustained in defensive collisions. Wide running forwards had the lowest incidence of injury, and the adjustables and outside backs had the highest incidence of injury.
  
  
  CONCLUSIONS
  These results highlight the physical demands associated with collisions and tackles in professional rugby league. Furthermore, the results of this study suggest that playing position and the type of collision sustained have a greater influence over contact injury risk in rugby league than the number of physical collisions performed.
authors.affiliation: School of Exercise Science, Australian Catholic University, Australia. tim gabbett@yahoo.com.au
authors.forename: Tim J
authors.initials: TJ
authors.lastname: Gabbett
authors.forename: David G
authors.initials: DG
authors.lastname: Jenkins
authors.forename: Bruce
authors.initials: B
authors.lastname: Abernethy
mesh_terms: D000059:Accidents / Q000706:statistics & numerical data*; D000293:Adolescent; D000328:Adult; D001265:Athletic Injuries / Q000453:epidemiology / Q000209:etiology*; D005538:Football / Q000293:injuries* / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D008297:Male; D011446:Prospective Studies; D014741:Video Recording; D055815:Young Adult