Adherence to 24-hour movement guidelines: Cognitive effects in Australian preschoolers

Background: Regular engagement in physical activity (PA), reduced screen-based sedentary time, or adequate sleep duration is independently linked to cognitive benefits, but such associations in an integrated manner have been rarely investigated with longitudinal design, especially among preschoolers. Methods: This longitudinal study explored associations between 24-hour movement guideline adherence and cognitive outcomes in 157 Australian preschoolers (M = 4.48 years, SD = 0.35, 52.2 % female). Using baseline parent-reported movement behaviours and direct cognitive assessments at 7-month and 1-year follow-up, we applied linear mixed regression models, adjusted for age, sex, maternal education, family income, and continuous PA, sleep, and screen time measures. Results: Meeting PA guidelines alone significantly predicted higher school readiness at 7 months (Estimate = 22.42, 95 % CI 9.56–35.28, p = 0.001, d = 1.40) and 1-year follow-up (Estimate = 22.54, 95 % CI 13.29–31.78, p < 0.001, d = 1.41), and enhanced cognitive flexibility at 1-year follow-up (Estimate = 4.01, 95 % CI 2.10–5.93, p < 0.001, d = 0.94). Sleep guideline adherence also predicted higher flexibility 1-year follow-up (Estimate = 1.82, 95 % CI 0.66–2.97, p = 0.002, d = 0.43). All other β estimates were non-significant after Bonferroni correction. Only 17.2 % of the involved preschoolers met all guidelines. Conclusion: Supporting adherence to the 24-Hour Movement Guidelines could enhance school readiness within one academic year.