Stand-Biased Versus Seated Classrooms and Childhood Obesity: A Randomized Experiment in Texas

Objectives. To measure changes in body mass index (BMI) percentiles among third-and fourth-grade students in stand-biased classrooms and traditional seated classrooms in 3 Texas elementary schools. Methods. Research staff recorded the height and weight of 380 students in 24 classrooms across the 3 schools at the beginning (2011-2012) and end (2012-2013) of the 2-year study. Results. After adjustment for grade, race/ethnicity, and gender, there was a statistically significant decrease in BMI percentile in the group that used stand-biased desks for 2 consecutive years relative to the group that used standard desks during both years. Mean BMI increased by 0.1 and 0.4 kilograms per meter squared in the treatment and control groups, respectively. The between-group difference in BMI percentile change was 5.24 (SE = 2.50; P = .037). No other covariates had a statistically significant impact on BMI percentile changes. Conclusions. Changing a classroom to a stand-biased environment had a significant effect on students' BMI percentile, indicating the need to redesign traditional classroom environments.