School Lunch Timing and Children's Physical Activity During Recess: an Exploratory Study.

Objective: To examine the relationship between school lunch timing (before vs after recess) on physical activity (PA) during recess and energy balance and food intake at lunch. Methods: A cross-sectional study design was used to examine lunch intake and PA during recess among fourth- and fifth-graders (n = 103) over 5 school days. Lunch and PA were measured using a weighted plate waste technique and accelerometry, respectively. Results: Children who received lunch before recess accumulated lower residual energy (ie, energy intake at lunch minus energy expenditure during recess) and consumed a greater proportion of milk servings. No timing effects were observed for other lunch and PA variables. Conclusions and Implications: Lunch intake and activity during recess are related to lunch timing policy. Findings warrant further examination using experimental and quasi-experimental studies to better understand the impact of timing on health behaviors.