AbstractChildren with developmental coordination disorder (DCD) have reduced fitness, executive functioning (EF), and self-regulation compared to typically developing (TD) children; however, the impact this has on endurance performance has yet to be examined. The purpose of this study was to determine the influence of self-regulation and EF on endurance performance in children with motor coordination difficulties. Self-regulation and EF were assessed using the internalizing and externalizing subscales of the Child Behaviour Checklist completed by the person most knowledgeable of the child. Motor coordination was assessed using the Movement Assessment Battery for Children, Second Edition (MABC-2). Endurance performance was assessed by a maximal treadmill test using the Bruce protocol. ANOVAs were used to compare differences between children at risk for DCD (rDCD; scoring at or below the 16th percentile on the MABC-2) and TD children, while controlling for age and sex. Mediation analyses were performed while also controlling for age and sex. Of the total sample (n=559, Mage=4.9 Â± 0.6 years), 270 (n=178 boys) children were classified as rDCD. Children with rDCD were found to have lower endurance performance (p<0.001), and greater internalizing (p<0.001) and externalizing (p <0.001) self-regulatory problems. The relationship between rDCD and endurance performance was mediated by internalizing problems (95% CI = -5.19, -0.53), but not externalizing problems (95% CI = -4.71, 0.31). Given the motor difficulties experienced among children with DCD, these findings highlight non-physical self-regulatory training as a possible technique to improve endurance exercise performance and EF in children with motor coordination difficulties.
Acknowledgments: We would like to acknowledge the Canadian Institute for Health Research for funding the CATCH project.