Associations Between 24-Hour Movement Behaviors and Anthropometric and Body Composition Indicators in Ecuadorian Preschool Children: SUNRISE Pilot Study

Objective: To analyze associations between 24-hour movement behaviors (and guideline adherence) and anthropometric and body composition indicators in Ecuadorian preschoolers using data from the International Study of Movement Behaviors in the Early Years (SUNRISE) pilot study. Methods: This secondary analysis utilized data from the primary study conducted in 108 children aged 3–4 years (57.4% girls; 50.9% urban). Anthropometry (weight, height, and body mass index [BMI]) was assessed using standardized protocols during the pilot study, whereas body composition indicators (fat-free mass [FFM], fat mass [FM], and body fat percentage) were estimated using a validated anthropometric prediction equation. Movement behaviors were assessed via triaxial accelerometry (ActiGraph GT3X+ or GT3X-BT, Pensacola, FL, USA) over seven days, complemented by parent-reported questionnaires. Exploratory unadjusted correlation analyses were performed using Spearman’s rho (ρ) for continuous/ordinal variables, and Pearson’s correlations (r), mathematically equivalent to point-biserial correlations (rpb), for dichotomous–continuous associations. Results: In exploratory unadjusted analyses, device-measured longer sleep duration showed small-to-moderate inverse associations with weight (ρ = −0.33, p = 0.001), BMI (ρ = −0.28, p = 0.006), and FFM (ρ = −0.37, p < 0.001). Higher moderate-to-vigorous physical activity showed moderate positive associations with height (ρ = 0.32, p = 0.002), weight (ρ = 0.40, p < 0.001), and FFM (ρ = 0.44, p < 0.001). In complementary multivariable models, the associations between device-measured sleep or moderate-to-vigorous physical activity (MVPA) and the pre-specified anthropometric and body composition outcomes were attenuated after adjustment for age, sex, area of residence, and, where applicable, height, and were generally not statistically significant. Conclusions: In this exploratory secondary analysis of the SUNRISE Pilot Study Ecuador, unadjusted analyses identified associations between specific 24-hour movement behaviors, particularly sleep duration and MVPA, and anthropometric and body composition indicators. However, these associations were attenuated after covariate adjustment. The findings should therefore be interpreted as hypothesis-generating and require confirmation in larger longitudinal studies.