title: Effects of a 'school-based' physical activity intervention on adiposity in adolescents from economically disadvantaged communities: secondary outcomes of the 'Physical Activity 4 Everyone' RCT.
abstract: Obesity prevention during adolescence is a health priority. The 'Physical Activity 4 Everyone' (PA4E1) study tested a multi-component physical activity intervention in 10 secondary schools from socio-economically disadvantaged communities. This paper aimed to report the secondary outcomes of the study; to determine whether the intervention impacted on adiposity outcomes (weight, body mass index (BMI), BMI z-score), and whether any effect was moderated by sex, baseline BMI and baseline physical activity level, at 12 and 24 months.
  
  
  
  A cluster randomised controlled trial was conducted in New South Wales, Australia. The school-based intervention included seven physical activity strategies targeting the following: curriculum (strategies to maximise physical activity in physical education, student physical activity plans, an enhanced school sport programme); school environment (physical activity during school breaks, modification of school policy); and parents and the community (parent engagement, links with community physical activity providers). Students' weight (kg), BMI and BMI z-score, were collected at baseline (Grade 7), 12 and 24 months. Linear Mixed Models were used to assess between-group mean difference from baseline to 12 and 24 months. Exploratory sub-analyses were undertaken according to three moderators of energy balance.
  
  
  
  A total of 1150 students (mean age=12 years) provided outcome data at baseline, 1051 (91%) at 12 months and 985 (86%) at 24 months. At 12 months, there were group-by-time effects for weight (mean difference=-0.90 kg (95% confidence interval (CI)=-1.50, -0.30), P<0.01) and BMI (-0.28 kg m-2(-0.50, -0.06), P=0.01) in favour of the intervention group, but not for BMI z-score (-0.05 (-0.11; 0.01), P=0.13). These findings were consistent for weight (-0.62 kg (-1.21, 0.03), P=0.01) and BMI (-0.28 kg m-2(-0.49, -0.06), P=0.01) at 24 months, with group-by-time effects also found for BMI z-score (-0.08 (-0.14; -0.02), P=0.02) favouring the intervention group.
  
  
  
  The PA4E1 school-based intervention achieved moderate reductions in adiposity among adolescents from socio-economically disadvantaged communities. Multi-component interventions that increase adolescents' engagement in moderate-to-vigorous physical activity (MVPA) may assist in preventing unhealthy weight gain.
authors.affiliation: Hunter New England Population Health, The University of Newcastle, Wallsend, New South Wales, Australia.|School of Medicine and Public Health, University of Newcastle, Callaghan, New South Wales, Australia.
authors.forename: J L
authors.initials: JL
authors.lastname: Hollis
authors.affiliation: Hunter New England Population Health, The University of Newcastle, Wallsend, New South Wales, Australia.|School of Medicine and Public Health, University of Newcastle, Callaghan, New South Wales, Australia.|Hunter Medical Research Institute, Lambton, New South Wales, Australia.
authors.forename: R
authors.initials: R
authors.lastname: Sutherland
authors.affiliation: Hunter New England Population Health, The University of Newcastle, Wallsend, New South Wales, Australia.|School of Medicine and Public Health, University of Newcastle, Callaghan, New South Wales, Australia.|Hunter Medical Research Institute, Lambton, New South Wales, Australia.
authors.forename: L
authors.initials: L
authors.lastname: Campbell
authors.affiliation: Priority Research Centre in Physical Activity and Nutrition, School of Education, University of Newcastle, Callaghan, New South Wales, Australia.
authors.forename: P J
authors.initials: PJ
authors.lastname: Morgan
authors.affiliation: Priority Research Centre in Physical Activity and Nutrition, School of Education, University of Newcastle, Callaghan, New South Wales, Australia.
authors.forename: D R
authors.initials: DR
authors.lastname: Lubans
authors.affiliation: Hunter New England Population Health, The University of Newcastle, Wallsend, New South Wales, Australia.|School of Medicine and Public Health, University of Newcastle, Callaghan, New South Wales, Australia.|Hunter Medical Research Institute, Lambton, New South Wales, Australia.
authors.forename: N
authors.initials: N
authors.lastname: Nathan
authors.affiliation: Hunter New England Population Health, The University of Newcastle, Wallsend, New South Wales, Australia.|School of Medicine and Public Health, University of Newcastle, Callaghan, New South Wales, Australia.|Hunter Medical Research Institute, Lambton, New South Wales, Australia.
authors.forename: L
authors.initials: L
authors.lastname: Wolfenden
authors.affiliation: Early Start Research Institute, Faculty of Social Sciences, University of Wollongong, Wollongong, New South Wales, Australia.|Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, New South Wales, Australia.
authors.forename: A D
authors.initials: AD
authors.lastname: Okely
authors.affiliation: Hunter New England Population Health, The University of Newcastle, Wallsend, New South Wales, Australia.|Hunter Medical Research Institute, Lambton, New South Wales, Australia.
authors.forename: L
authors.initials: L
authors.lastname: Davies
authors.affiliation: Hunter New England Population Health, The University of Newcastle, Wallsend, New South Wales, Australia.|School of Medicine and Public Health, University of Newcastle, Callaghan, New South Wales, Australia.
authors.forename: A
authors.initials: A
authors.lastname: Williams
authors.affiliation: Priority Research Centre in Physical Activity and Nutrition, School of Education, University of Newcastle, Callaghan, New South Wales, Australia.
authors.forename: K E
authors.initials: KE
authors.lastname: Cohen
authors.affiliation: School of Medicine and Public Health, University of Newcastle, Callaghan, New South Wales, Australia.|Hunter Medical Research Institute, Lambton, New South Wales, Australia.
authors.forename: C
authors.initials: C
authors.lastname: Oldmeadow
authors.affiliation: Hunter New England Population Health, The University of Newcastle, Wallsend, New South Wales, Australia.|Hunter Medical Research Institute, Lambton, New South Wales, Australia.
authors.forename: K
authors.initials: K
authors.lastname: Gillham
authors.affiliation: Hunter New England Population Health, The University of Newcastle, Wallsend, New South Wales, Australia.|School of Medicine and Public Health, University of Newcastle, Callaghan, New South Wales, Australia.|Hunter Medical Research Institute, Lambton, New South Wales, Australia.
authors.forename: J
authors.initials: J
authors.lastname: Wiggers
mesh_terms: D050154:Adiposity; D000293:Adolescent; D001315:Australia / Q000453:epidemiology; D002648:Child; D003362:Cost-Benefit Analysis; D015444:Exercise / Q000502:physiology* / Q000523:psychology; D005260:Female; D015438:Health Behavior; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D063766:Pediatric Obesity / Q000453:epidemiology / Q000517:prevention & control* / Q000523:psychology; D015397:Program Evaluation; D012572:School Health Services; D012959:Socioeconomic Factors; D013334:Students / Q000523:psychology