Body Composition and Adiposity in Children with Down Syndrome Compared to Typically Developing Children: The Association with Their Motor Performance

<b>Background/Objectives:</b> Children with DS are at an increased risk of obesity and impaired motor performance. This study aimed to compare body composition and motor performance in children with DS and typically developing (TD) peers and to explore associations between adiposity and motor function. <b>Methods:</b> A cross-sectional study was conducted with 42 children aged 6-12 years (23 DS, 19 TD). Body composition was assessed using bioelectrical impedance analysis. Postural stability was evaluated with the Pediatric Balance Scale; hand grip strength with hand dynamometry; physical activity with the PAQ-C; and aerobic endurance with the YMCA 3 min step test. <b>Results</b>: Children with DS exhibited significantly higher adiposity and lower motor performance than their TD peers. In the DS group, body fat mass was negatively correlated with physical activity (r = -0.499, <i>p</i> = 0.018), balance (r = -0.684, <i>p</i> < 0.001), and aerobic endurance (r = -0.389, <i>p</i> < 0.073). Regression analysis identified physical activity and fitness level as significant predictors of BMI in children with DS (R² = 0.825). <b>Conclusions</b>: Children with DS exhibit higher adiposity and inferior motor performance compared to their TD peers, with strong associations between adiposity and reduced physical activity, balance, and aerobic endurance. These findings underscore the importance of early targeted interventions to improve health outcomes in children with DS, particularly in regions like Saudi Arabia, where prevalence is high.