title: Changes in knee joint biomechanics following balance and technique training and a season of Australian football.
abstract: OBJECTIVE
  Determine if balance and technique training (BTT) implemented adjunct to normal Australian football (AF) training reduces external knee loading during sidestepping. Additionally, the authors determined if an athlete's knee joint kinematics and kinetics change over a season of AF.
  
  
  METHODS
  Eight amateur-level AF clubs (n=1,001 males) volunteered to participate in either 28 weeks of BTT or a 'sham' training (ST) adjunct to their normal preseason and regular training. A subset of 34 athletes (BTT, n=20; ST, n=14) were recruited for biomechanical testing in weeks 1-7 and 18-25 of the 28-week training intervention. During biomechanical testing, participants completed a series running, preplanned (PpSS) and unplanned sidestepping (UnSS) tasks. A linear mixed model (α=0.05) was used to determine if knee kinematics and peak moments during PpSS and UnSS were influenced by BTT and/or a season of AF.
  
  
  RESULTS
  Both training groups significantly (p=0.025) decreased their peak internal-rotation knee moments during PpSS, and significantly (p=0.022) increased their peak valgus knee moments during UnSS following their respective training interventions.
  
  
  CONCLUSIONS
  BTT was not effective in changing an athlete's knee joint biomechanics during sidestepping when conducted in 'real-world' training environments. Following normal AF training, the players had different changes to their knee joint biomechanics during both preplanned and unplanned sidestepping. When performing an unplanned sidestepping task in the latter half of a playing season, athletes are at an increased risk of ACL injury. The authors therefore recommend both sidestepping tasks are performed during biomechanical testing when assessing the effectiveness of prophylactic training protocols.
authors.affiliation: The University of Western Australia, School of Sport Science, Exercise and Health, 35 Stirling Highway, Perth, Western Australia 6009, Australia. cyril.donnelly@uwa.edu.au
authors.forename: Cyril J
authors.initials: CJ
authors.lastname: Donnelly
authors.forename: Bruce C
authors.initials: BC
authors.lastname: Elliott
authors.forename: Tim L A
authors.initials: TL
authors.lastname: Doyle
authors.forename: Caroline F
authors.initials: CF
authors.lastname: Finch
authors.forename: Alasdair R
authors.initials: AR
authors.lastname: Dempsey
authors.forename: David G
authors.initials: DG
authors.lastname: Lloyd
mesh_terms: D000704:Analysis of Variance; D001696:Biomechanical Phenomena / Q000502:physiology; D005538:Football / Q000502:physiology*; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D008297:Male; D004856:Postural Balance / Q000502:physiology; D016059:Range of Motion, Articular / Q000502:physiology; D012399:Rotation; D012420:Running / Q000502:physiology; D014904:Western Australia; D055815:Young Adult