title: Kinetic asymmetries during running in male youth.
abstract: OBJECTIVE
  A possible injury risk factor is limb asymmetry, which may differ across maturation given the adult growth spurt. The aim of this study is to quantify the magnitude of asymmetry in a number of kinetic variables during a running task in male youth of different maturity status.
  
  
  METHODS
  Quantitative observational laboratory study.
  
  
  METHODS
  Sports performance laboratory.
  
  
  METHODS
  Non-injured youth athletes in pre-, mid-, and post-pubescent status.
  
  
  METHODS
  Inter-limb leg asymmetries whilst sprinting on a non-motorized treadmill. Percent asymmetry was defined as: (Left leg - right leg)/right leg*100 = %asymmetry.
  
  
  RESULTS
  Horizontal force presented limb asymmetries of 15.4, 14.8 and 14.7% for the pre-, mid- and post-PHV group respectively. Values for vertical force were higher (18.1, 20.2 and 20.8% respectively). Power asymmetries were 14.9, 15.8, and 15.5% respectively and work asymmetries were significant higher in pre-PHV participants (26.4%) compared to mid- (14.7%) and post-PHV (17.3%) participants.
  
  
  CONCLUSIONS
  As the population in this study was characterized as non-injured, asymmetries of 15-20% appeared typical during a running task in developmental athletes.
authors.affiliation: Sport Performance Research Institute New Zealand, AUT University, 90 Akoranga Drive North Shore, Auckland, New Zealand; New Zealand Football, Lion Foundation House, Albany, Auckland, New Zealand. Electronic address: rumpf.michael@web.de.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Rumpf
authors.affiliation: Sport Performance Research Institute New Zealand, AUT University, 90 Akoranga Drive North Shore, Auckland, New Zealand; School of Exercise, Biomedical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, Western Australia 6027, Australia. Electronic address: jcronin@aut.ac.nz.
authors.forename: John B
authors.initials: JB
authors.lastname: Cronin
authors.affiliation: Sultan Idris Education University, 35900 Tanjong Malim, Pera Perak, Malaysia. Electronic address: nurmupsi@gmail.com.
authors.forename: Ikhwan N
authors.initials: IN
authors.lastname: Mohamad
authors.affiliation: National Sport Institute Malaysia, Bukit Jalil, Kuala Lumpur 50714, Malaysia. Electronic address: sharilmohd@gmail.com.
authors.forename: Sharil
authors.initials: S
authors.lastname: Mohamad
authors.affiliation: Cardiff School of Sport, Western Avenue, Cardiff Metropolitan University, Cardiff, Wales, UK. Electronic address: joliver@cardiffmet.ac.uk.
authors.forename: Jon L
authors.initials: JL
authors.lastname: Oliver
authors.affiliation: Cardiff School of Sport, Western Avenue, Cardiff Metropolitan University, Cardiff, Wales, UK. Electronic address: mghughes@cardiffmet.ac.uk.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Hughes
mesh_terms: D000293:Adolescent; D001696:Biomechanical Phenomena; D002648:Child; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D007866:Leg / Q000502:physiology*; D008297:Male; D012420:Running / Q000502:physiology*
keywords: Biomechanics; Imbalance; Injury prevention; Kinetics