title: Accelerometry-assessed sedentary behaviour and physical activity levels during the segmented school day in 10-14-year-old children: the HAPPY study.
abstract: The school day offers several different time periods that provide varying opportunities for sedentary time (SED) and engagement in physical activity (PA), yet little is known about the PA and sedentary behaviour patterns of boys and girls during these times. The volume, intensity and temporal distributions of SED and PA undertaken by 135 schoolchildren aged 10-14 years, during different segments of the school day: (a) school transport, (b) morning recess, (c) lunch break, (d) class time and (e) after school, were explored using triaxial accelerometry. PA was categorised into SED, light PA (LPA), moderate PA (MPA) and vigorous PA (VPA). Girls engaged in significantly more SED and LPA than boys during recess and lunch break (p < 0.05), while boys engaged in significantly higher levels of VPA during recess (p < 0.001) and MPA and VPA during lunch break (p < 0.001). PA engagement was similar between sexes during other segments of the day.
  
  
  CONCLUSIONS
  PA patterns appear more beneficial for health in boys during less structured school-based time periods and interventions may therefore target opportunities for girls to be physically active during these times to overcome this observed sex deficit.
authors.affiliation: Institute for Sport and Physical Activity Research, University of Bedfordshire, Polhill Avenue, Bedford, Bedfordshire, MK41 9EA, UK. daniel.bailey@beds.ac.uk
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Bailey
authors.forename: Stuart J
authors.initials: SJ
authors.lastname: Fairclough
authors.forename: Louise A
authors.initials: LA
authors.lastname: Savory
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Denton
authors.forename: Dong
authors.initials: D
authors.lastname: Pang
authors.forename: Colleen S
authors.initials: CS
authors.lastname: Deane
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Kerr
mesh_terms: D061725:Accelerometry / Q000379:methods; D000293:Adolescent; D000465:Algorithms; D000704:Analysis of Variance; D015992:Body Mass Index; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity; D009765:Obesity / Q000517:prevention & control; D012307:Risk Factors; D012494:Sampling Studies; D012574:Schools; D057185:Sedentary Behavior; D012737:Sex Factors; D013997:Time Factors