TY - JOUR
T1 - Impact of a year-round school calendar on children's BMI and fitness
T2 - Final outcomes from a natural experiment
AU - Weaver, Robert Glenn
AU - Hunt, Ethan
AU - Armstrong, Bridget
AU - Beets, Michael W.
AU - Brazendale, Keith
AU - Turner-McGrievy, Gabrielle
AU - Pate, Russell R.
AU - Maydeu-Olivares, Alberto
AU - Saelens, Brian
AU - Youngstedt, Shawn D.
AU - Dugger, Roddrick
AU - Parker, Hannah
AU - von Klinggraeff, Lauren
AU - Jones, Alexis
AU - Burkhart, Sarah
AU - Ressor-Oyer, Layton
N1 - Funding Information:
Research reported in this publication was supported in part by the Eunice Kennedy Shriver National Institute of Child Health & Human Development of the National Institutes of Health under Award Number R21HD095164 and the National Institute of General Medical Sciences Award Number P20GM130420. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
Publisher Copyright:
© 2021 World Obesity Federation
PY - 2021/10
Y1 - 2021/10
N2 - Background: Structure may mitigate children's accelerated summer BMI gain and cardiorespiratory-fitness (CRF) loss. Objectives: Examine BMI and CRF change during school and summer for year-round and traditional calendar school children. Methods: Three schools (N = 2279, 1 year-round) participated in this natural experiment. Children's BMI z-score (zBMI) and CRF (PACER laps) were measured from 2017 to 2019 each May/August. Mixed effects regression estimated monthly zBMI and CRF change during school/summer. Secondary analyses examined differences by weight status and race. Spline regression models estimated zBMI and CRF growth from kindergarten-sixth grade. Results: Compared to traditional school, children attending a year-round school gained more zBMI (difference = 0.015; 95CI = 0.002, 0.028) during school, and less zBMI (difference = −0.029; 95CI = −0.041, −0.018), and more CRF (difference = 0.834; 95CI = 0.575, 1.093) monthly during summer. Differences by weight status and race were observed during summer and school. Growth models demonstrated that the magnitude of overall zBMI and CRF change from kindergarten-sixth grade was similar for year-round or traditional school children. Conclusions: Contrary to traditional school children zBMI increased during the traditional 9-month school calendar and zBMI decreased during the traditional summer vacation for year-round school children. Structured summer programming may mitigate accelerated summer BMI gain and CRF loss especially for overweight or obese, and/or Black children.
AB - Background: Structure may mitigate children's accelerated summer BMI gain and cardiorespiratory-fitness (CRF) loss. Objectives: Examine BMI and CRF change during school and summer for year-round and traditional calendar school children. Methods: Three schools (N = 2279, 1 year-round) participated in this natural experiment. Children's BMI z-score (zBMI) and CRF (PACER laps) were measured from 2017 to 2019 each May/August. Mixed effects regression estimated monthly zBMI and CRF change during school/summer. Secondary analyses examined differences by weight status and race. Spline regression models estimated zBMI and CRF growth from kindergarten-sixth grade. Results: Compared to traditional school, children attending a year-round school gained more zBMI (difference = 0.015; 95CI = 0.002, 0.028) during school, and less zBMI (difference = −0.029; 95CI = −0.041, −0.018), and more CRF (difference = 0.834; 95CI = 0.575, 1.093) monthly during summer. Differences by weight status and race were observed during summer and school. Growth models demonstrated that the magnitude of overall zBMI and CRF change from kindergarten-sixth grade was similar for year-round or traditional school children. Conclusions: Contrary to traditional school children zBMI increased during the traditional 9-month school calendar and zBMI decreased during the traditional summer vacation for year-round school children. Structured summer programming may mitigate accelerated summer BMI gain and CRF loss especially for overweight or obese, and/or Black children.
KW - children
KW - obesity
KW - policy
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U2 - 10.1111/ijpo.12789
DO - 10.1111/ijpo.12789
M3 - Article
C2 - 33763967
AN - SCOPUS:85103059425
SN - 2047-6302
VL - 16
JO - Pediatric Obesity
JF - Pediatric Obesity
IS - 10
M1 - e12789
ER -