Interdependency between physical education and food environment in school on students’ energy balance: an agent‐based model

Background Requiring students to attend physical education (PE) class can promote their physical activity (PA) in school, while vending machine and soda are prevalent in middle schools in the US. Objective To test the complex interactions between students’ PA, school environment, and students’ water/beverage drinking choices and energy intake. Methods Agent‐based models (ABM), a system science model, simulated students’ energy expenditure (EE) during PE, their dehydration, and fluid intake through soda vending machine and/or water fountains. The models incorporated physiological dynamics of human body water during exercise and individual economical decision making rules. Results The models showed higher prevalence of dehydration status for longer PE duration, which took time after PE to rehydrate. Average offset of EE due to the presence of vending machine in school ranged 40–70 kcal/person. The offset expanded with longer PE, but shrank with more water fountains in school. Conclusions The simulation revealed the benefit of extending PE on EE, its potential effect on students’ dehydration, and the competition between soda vending machines and water fountains on the offset of EE. Systems models can help evaluate the benefits and unintended consequences of environment intervention programs, by integrating behavioral rules on the complex relationships between environment and human behaviors. Grant Funding Source : NIH (3U54HD070725–02S1, 1R01HD064685–01A1)