title: Disparities in moderate-to-vigorous physical activity among girls and overweight and obese schoolchildren during school- and out-of-school time.
abstract: BACKGROUND
  Increasing physical activity (PA) during the school day and out-of-school time are critical strategies for preventing childhood obesity and improving overall health. The purpose of the present investigation was to examine schoolchildren's volume and type of PA during school-time and out-of-school, compared to national recommendations and differences by sex and weight status.
  
  
  METHODS
  This cross-sectional analysis included 517 3(rd)-5(th) grade schoolchildren from 13 New England elementary schools (October 2013-January 2014). Demographics were collected by parent questionnaire. Measured height and weight were used to categorize child weight status. Accelerometer data were collected over 7 days. PA was coded as total activity counts and minutes of sedentary, light, and moderate-to-vigorous physical activity (SED, LPA, MVPA) during 1) school, 2) weekday out-of-school, 3) weekend, and 4) total daily time. Multivariable mixed models were used to examine associations between sex and weight status and total counts, SED, LPA, and MVPA, controlling for demographics, wear-time, and clustering within schools.
  
  
  RESULTS
  453 participants (60.5% girls; mean age 9.1 years; 30.5% overweight/obese) had valid accelerometer wear time (≥3 days, ≥ 10 h/day). Few children achieved 60 min total daily (15.0%) or school-time (8.0 %) MVPA recommendations. For all time-of-day categories, girls achieved fewer MVPA minutes than boys (p < .0001), and overweight/obese participants achieved fewer MVPA minutes than normal/underweight participants (p = 0.05). Minutes of LPA declined by grade-level (p < .05) and were lower in girls than boys during school-time only (p < .05).
  
  
  CONCLUSIONS
  Disparities in MVPA by sex and weight status across school and out-of-school time highlight the need for programs with equitable reach.
authors.affiliation: Tufts University School of Medicine, Public Health and Community Medicine, 145 Harrison Avenue, Boston, MA, 02111, USA. Kristie.hubbard@tufts.edu.
authors.forename: Kristie
authors.initials: K
authors.lastname: Hubbard
authors.affiliation: ChildObesity180, Friedman School of Nutrition Science and Policy, Tufts University, 150 Harrison Avenue, Boston, MA, 02111, USA.
authors.forename: Christina D
authors.initials: CD
authors.lastname: Economos
authors.affiliation: ChildObesity180, Friedman School of Nutrition Science and Policy, Tufts University, 150 Harrison Avenue, Boston, MA, 02111, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Bakun
authors.affiliation: University of New England, School of Community and Population Health, 11 Hills Beach Rd, Biddeford, ME, 04005, USA.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Boulos
authors.affiliation: Tufts University School of Medicine, Public Health and Community Medicine, 145 Harrison Avenue, Boston, MA, 02111, USA.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Chui
authors.affiliation: Friedman School of Nutrition Science and Policy, Tufts University, 150 Harrison Avenue, Boston, MA, 02111, USA.
authors.forename: Megan P
authors.initials: MP
authors.lastname: Mueller
authors.affiliation: ChildObesity180, Friedman School of Nutrition Science and Policy, Tufts University, 150 Harrison Avenue, Boston, MA, 02111, USA.
authors.forename: Katie
authors.initials: K
authors.lastname: Smith
authors.affiliation: Friedman School of Nutrition Science and Policy, Tufts University, 150 Harrison Avenue, Boston, MA, 02111, USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Sacheck
mesh_terms: D001835:Body Weight; D002648:Child; D003430:Cross-Sectional Studies; D015444:Exercise; D005260:Female; D006801:Humans; D007899:Leisure Activities; D008297:Male; D009043:Motor Activity; D009511:New England; D050177:Overweight; D063766:Pediatric Obesity / Q000517:prevention & control; D005082:Physical Exertion; D012574:Schools; D012737:Sex Factors; D013851:Thinness