title: A systematic review and meta-analysis of moderate-to-vigorous physical activity levels in elementary school physical education lessons.
abstract: OBJECTIVE
  To examine elementary school students' moderate-to-vigorous physical activity (MVPA) levels during physical education (PE) lessons.
  
  
  METHODS
  A systematic search of nine electronic databases was conducted (PROSPERO2014:CRD42014009649). Studies were eligible if they were in English; published between 2005-April 2014; assessed MVPA levels in PE lessons of elementary school children (aged four-12years); and used an objective MVPA measure. Two reviewers retrieved articles, assessed risk of bias, and performed data extraction. The findings were synthesised using a meta-analysis.
  
  
  RESULTS
  The search yielded 5132 articles. Thirteen studies from nine countries met the inclusion criteria. Eight studies measured MVPA through observational measures, five used accelerometry and one used heart rate monitoring. The percentage of PE lesson time spent in MVPA ranged between 11.4-88.5%. Meta-analysis of seven studies (4 direct observations; 4 accelerometers) found that children spent a mean (95% CI) 44.8 (28.2-61.4)% of PE lesson time in MVPA. When measured using direct observation and accelerometers, children spent 57.6 (47.3-68.2) and 32.6 (5.9-59.3)% of PE lesson time in MVPA, respectively. The review has limitations; the search strategy was restricted to studies in English; theses, dissertations and conference abstracts were excluded; and six studies that provided insufficient data were excluded from the meta-analysis.
  
  
  CONCLUSIONS
  MVPA levels during elementary school PE lessons do not meet the United States Centre for Disease Control and Prevention and the United Kingdom's Association of Physical Education recommendation (50% of lesson time), but is higher than estimated in the previous review (34.2%). Interventions to increase MVPA in PE lessons are needed.
authors.affiliation: Hunter New England Population Health, Locked Bag 10, Wallsend, NSW 2287, Australia; School of Medicine and Public Health, University of Newcastle, Callaghan 2308, Australia. Electronic address: jenna.hollis@abdn.ac.uk.
authors.forename: Jenna L
authors.initials: JL
authors.lastname: Hollis
authors.affiliation: Hunter New England Population Health, Locked Bag 10, Wallsend, NSW 2287, Australia; School of Medicine and Public Health, University of Newcastle, Callaghan 2308, Australia; Hunter Medical Research Institute, Lambton, NSW 2305, Australia. Electronic address: Amanda.J.Williams@hnehealth.nsw.gov.au.
authors.forename: Amanda J
authors.initials: AJ
authors.lastname: Williams
authors.affiliation: Hunter New England Population Health, Locked Bag 10, Wallsend, NSW 2287, Australia; School of Medicine and Public Health, University of Newcastle, Callaghan 2308, Australia; Hunter Medical Research Institute, Lambton, NSW 2305, Australia. Electronic address: Rachel.Sutherland@hnehealth.nsw.gov.au.
authors.forename: Rachel
authors.initials: R
authors.lastname: Sutherland
authors.affiliation: Hunter New England Population Health, Locked Bag 10, Wallsend, NSW 2287, Australia; School of Medicine and Public Health, University of Newcastle, Callaghan 2308, Australia; Hunter Medical Research Institute, Lambton, NSW 2305, Australia. Electronic address: Libby.Campbell@hnehealth.nsw.gov.au.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Campbell
authors.affiliation: Hunter New England Population Health, Locked Bag 10, Wallsend, NSW 2287, Australia; School of Medicine and Public Health, University of Newcastle, Callaghan 2308, Australia; Hunter Medical Research Institute, Lambton, NSW 2305, Australia. Electronic address: Nicole.Nathan@hnehealth.nsw.gov.au.
authors.forename: Nicole
authors.initials: N
authors.lastname: Nathan
authors.affiliation: Hunter New England Population Health, Locked Bag 10, Wallsend, NSW 2287, Australia; School of Medicine and Public Health, University of Newcastle, Callaghan 2308, Australia; Hunter Medical Research Institute, Lambton, NSW 2305, Australia. Electronic address: Luke.Wolfenden@hnehealth.nsw.gov.au.
authors.forename: Luke
authors.initials: L
authors.lastname: Wolfenden
authors.affiliation: Priority Research Centre in Physical Activity and Nutrition, School of Education, University of Newcastle, Callaghan 2308, Australia. Electronic address: philip.morgan@newcastle.edu.au.
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Morgan
authors.affiliation: Priority Research Centre in Physical Activity and Nutrition, School of Education, University of Newcastle, Callaghan 2308, Australia. Electronic address: david.lubans@newcastle.edu.au.
authors.forename: David R
authors.initials: DR
authors.lastname: Lubans
authors.affiliation: Hunter New England Population Health, Locked Bag 10, Wallsend, NSW 2287, Australia; School of Medicine and Public Health, University of Newcastle, Callaghan 2308, Australia; Hunter Medical Research Institute, Lambton, NSW 2305, Australia. Electronic address: John.Wiggers@hnehealth.nsw.gov.au.
authors.forename: John
authors.initials: J
authors.lastname: Wiggers
mesh_terms: D061725:Accelerometry; D002648:Child; D006801:Humans; D010806:Physical Education and Training / Q000706:statistics & numerical data*; D005082:Physical Exertion; D012572:School Health Services; D013997:Time Factors
keywords: Child; Motor activity; Physical education and training; Schools