title: Active video games: the mediating effect of aerobic fitness on body composition.
abstract: BACKGROUND
  Increased understanding of why and how physical activity impacts on health outcomes is needed to increase the effectiveness of physical activity interventions. A recent randomized controlled trial of an active video game (PlayStation EyeToy™) intervention showed a statistically significant treatment effect on the primary outcome, change from baseline in body mass index (BMI), which favored the intervention group at 24 weeks. In this short paper we evaluate the mediating effects of the secondary outcomes.
  
  
  OBJECTIVE
  To identify mediators of the effect of an active video games intervention on body composition.
  
  
  METHODS
  Data from a two-arm parallel randomized controlled trial of an active video game intervention (n = 322) were analyzed. The primary outcome was change from baseline in BMI. A priori secondary outcomes were considered as potential mediators of the intervention on BMI, including aerobic fitness (VO2Max), time spent in moderate-to-vigorous physical activity (MVPA), and food snacking at 24 weeks.
  
  
  RESULTS
  Only aerobic fitness at 24 weeks met the conditions for mediation, and was a significant mediator of BMI.
  
  
  CONCLUSIONS
  Playing active video games can have a positive effect on body composition in overweight or obese children and this effect is most likely mediated through improved aerobic fitness. Future trials should examine other potential mediators related to this type of intervention.
  
  
  BACKGROUND
  Australian New Zealand Clinical Trials Registry Website: http://www.anzctr.org.au. Study ID number: ACTRN12607000632493.
authors.affiliation: Clinical Trials Research Unit, University of Auckland, Auckland, New Zealand. r.maddison@ctru.auckland.ac.nz
authors.forename: Ralph
authors.initials: R
authors.lastname: Maddison
authors.forename: Cliona Ni
authors.initials: CN
authors.lastname: Mhurchu
authors.forename: Andrew
authors.initials: A
authors.lastname: Jull
authors.forename: Harry
authors.initials: H
authors.lastname: Prapavessis
authors.forename: Louise S
authors.initials: LS
authors.lastname: Foley
authors.forename: Yannan
authors.initials: Y
authors.lastname: Jiang
mesh_terms: D000293:Adolescent; D001823:Body Composition; D015992:Body Mass Index; D002648:Child; D006801:Humans; D009043:Motor Activity; D009520:New Zealand; D009765:Obesity / Q000503:physiopathology / Q000628:therapy; D050177:Overweight / Q000503:physiopathology / Q000628:therapy; D062410:Snacks; D018910:Video Games