Objective: This systematic review and meta-analysis examined the effects of school-based interventions on all 24-hour movement behaviours. Design: Systematic review and meta-analysis. Data sources: Studies published in English, French, and Spanish from four databases from inception to February 2024 were identified. Eligibility criteria for selecting studies: Eligible articles were randomised controlled trials (RCTs) that targeted and assessed physical activity (PA), sedentary behaviour (SB) and sleep duration among school-aged youth (3–17 years). Risk of bias and quality assessment were assessed using the Risk of Bias Tool 2 and Quality Assessment of Controlled Intervention Studies tool, respectively. Grading of Recommendations, Assessment, Development and Evaluation (GRADE) tool evaluated the certainty of evidence. The study was registered in International Prospective Register of Systematic Reviews (PROSPERO) (ID: removed for peer review). Results: Of the 5141 records initially identified, 41 studies remained for full-text review. After full reading, 7 RCTs, comprising 8234 participants (49% girls), were included. Results indicated no effect in PA-related outcomes (Hedge’s g=0.12, –0.05 to 0.28), a small reduction in SB-related outcomes (g=−0.33, –0.51 to −0.16) and a small increase in sleep duration (g=0.30, 0.16 to 0.43) according to Hedges’ g (small effects (0≤g ≤0.50)). The GRADE, risk of bias and quality assessment tools indicated that most of the studies have a low risk of bias and are of good quality. Conclusions: More school-based interventions promoting all movement behaviours are needed to determine if schools are optimal for encouraging 24-hour movement behaviours among young people.

Three key health behaviors, physical activity (PA), sedentary behavior (SB) and sleep (SLP), have been identified by the 24-h framework as movement behaviors. School-based interventions targeting these multiple health behaviors among children have the potential to increase health outcomes. Despite this, the efficacy and sustainability of school-based movement behavior interventions among children has not been evaluated yet. To fill this gap in literature, this systematic review will aim to: (1) Summarize and classify movement behavior strategies used in literature to improve PA, SB and SLP in/from school in children; and (2) measure the effect of movement behavior strategies used in literature to improve PA, SB and SLP in children. The review protocol was registered in PROSPERO (CRD42020199154). A systematic search will be conducted between 2010 to 2020 in five databases: Pubmed, Scopus, SPORTDiscuss, The Cochrane Library and Web of Science. Risk of bias and quality assessment will be evaluated and measured according to the recommended tools. This systematic review will provide information about which kind of school-based movement behavior interventions are effective, sustainable and the best to implement in children.

Objective: 24-hour movement behaviours can effect sustainable long-term benefits in children, but their implementation and effectiveness have not previously been reviewed in the school setting. Thus, the aim of this scoping review was to provide an overview of school-based interventions targeting physical activity (PA), sedentary behaviour (SB), and sleep in 5–12-year-old children. Design: Scoping review. Methods: A structured bibliographic search of five databases was conducted to retrieve peer-reviewed intervention studies published in English language, between January 2010 and December 2020. Results: Among the 37 studies included with a total sample size of 27,145 primary school-aged children, only one study assessed sleep, PA and SB. The average duration of the intervention studies was between 7 and 10 months. Conclusion: The main gap identified was that current school-based interventions do not include complete 24-hour movement behaviours among children as there is a lack of intervention studies addressing sleep behaviour. In addition, this first international review of 24-hour movement behaviours in a school setting found that the number of intervention studies that incuded follow-up measures is limited, so it is difficult to interpret their sustainability.