How do children spend their time? : a quantitative analysis of physical activity in children on the autism spectrum

Autism spectrum disorder (ASD) is pervasive neurodevelopment disorder characterized by a broad range of social abnormalities and deficit in motor skills, many times referred to as clumsiness. These abnormal social characteristics result in a restricted repertoire of activity and interests that also may affect the motor learning process. Therefore, fewer opportunities to practice motor skills can lead to a delay in achieving motor proficiency. It is well known that physical activity and motor proficiency are positively correlated and the amount of time spent in a physical activity is directly related to the level of expertise in neurotypical children. Hence, the specific aim of this study is to quantify the amount of physical activity in children with ASD and compare this value to that of non-diagnosed siblings (ASD siblings) and neurotypical controls (NT), as well as to compare the amount of physical activity between neurotypical controls and ASD siblings. In this study, it was hypothesized that: 1) children with ASD would have lower scores than their non-diagnosed sibling and also than the NT controls in the amount of physical activity; 2) non-diagnosed siblings and neurotypical children would not be different in the amount of physical activity; 3) children with ASD's general score on the motor skills assessments would be lower than the non-diagnosed siblings and lower than NT controls; 4) There would not be a difference in the general score on motor skills assessments between non-diagnosed siblings and neurotypical children and 5) the motor assessments scores would be positively correlated (p < 0.05) to the amount of physical activity. There were differences between ASD and NT groups regarding to the amount of physical activity and also regarding to the motor proficiency scores. Although those differences were not statistically significant, they definitely are clinically relevant as showed that the children on the autism spectrum presented a clear motor delay. Likewise, the correlation between amount of physical activity and motor proficiency was showed not to be significant. These results can be explained by the small sample size. Further studies with a larger sample size would be crucial to verify these hypotheses proposed in the present study.