Background Children and adolescents with intellectual disabilities (ID) participate in low levels of physical activity. To inform the development of interventions, we need to better understand factors associated with physical activity. The aim of this study was therefore to systematically review correlates of physical activity in children and adolescents with ID. Methods The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidelines. Ovid MEDLINE, Ovid Embase, Web of Science, ERIC, CINAHL and PsycINFO were searched between 1 January 1990 and 29 February 2020 to identify English‐language studies, which examined correlates of free‐living physical activity in children and adolescents (0–19 years) with ID. Study quality was assessed. Correlates were analysed using a narrative synthesis and classified using the socioecological model as intrapersonal, interpersonal, organisational or environmental. Results Fifteen studies published between 2010 and 2019 met the inclusion criteria and were included in the review. Forty‐eight individual correlates were identified. Studies were predominantly focused on intrapersonal‐level correlates. Of those correlates investigated in more than one study (n = 6), having better motor development was positively associated with physical activity. Inconsistent results were found for age and cardiorespiratory fitness. Sex, percentage body fat and body mass index were not correlated. No interpersonal‐level, organisational‐level or environmental‐level correlates were included in more than one study. Conclusions To date, we have limited and inconclusive evidence about correlates of physical activity in children and adolescents with ID. Only when future studies unravel correlates and determinants, across all domains of the socioecological model, will the potential opportunities to improve health by increasing physical activity levels be achievable.

Introduction An active play is designed to increase children’s physical activity levels and fundamental movement skills through outdoor play and is well-suited to the needs of children with intellectual disabilities. However, no active play interventions have included children with intellectual disabilities. This study aims to investigate the feasibility of a school-based active play intervention for children with intellectual disabilities. Method Children aged 7–12 years who had intellectual disabilities and were independently ambulatory were eligible. This single-group 17-week intervention was implemented in two additional support needs schools. It consisted of a weekly 1-h active play session incorporating 30 min of structured games and 30 min of free play. Feasibility of recruitment/retention, adherence, and outcome measures were investigated. Outcome measures included school-based physical activity (ActiGraph GT3X+ accelerometer), fundamental movement skills (Test of Gross Motor Development-2), and social interactions (Playground Observation of Peer Engagement). Staff feedback was collected via open-ended questionnaire. Feasibility was investigated using descriptive statistics and questionnaire data analyzed using thematic analysis. Potential pre-post changes were investigated for school-based physical activity, fundamental movement skills, and social interactions using paired samples t tests. The progression criteria were (1) > 50% of eligible participants recruited, (2) > 50% of recruited participants retained, (3) > 50% of active play sessions spent in MVPA, and (4) > 50% of participants complete outcome measurements. Results All progression criteria were met. Recruitment and retention rates were 100% (n=21 participants). Intervention adherence was high, based on data from n=1 school, with 90% of participants attending all sessions. Measuring physical activity using accelerometry and fundamental movement skills using the Test of Gross Motor Development-2 were feasible. The Playground Observation of Peer Engagement tool to measure social interactions was not feasible. The only significant increase post-intervention was for social interactions during structured play (pre–post mean difference: –1.46, 95% CI −1.99, −0.93). Staff feedback was positive with the intervention well received by schools and potential benefits post-intervention identified by teachers. Conclusion The Go2Play Active Play intervention is feasible for children with intellectual disabilities. Future research should further investigate feasibility and implementation on a larger scale using a pilot cluster randomised controlled trial. Trial registration ISRCTN registry: ISRCTN10277566.