Measuring Physical Activity in Youth with Down Syndrome and Autism Spectrum Disorders: Identifying Data-Based Measurement Conditions.

Abstract

Few studies have paid attention to identifying physical activity (PA) in children and adolescents with disabilities using objective measures. The overall goal of this dissertation is to objectively measure PA in youth with Down syndrome (DS) and autism spectrum disorders (ASD) and to determine the minimum monitoring period needed for each group using data-based evidence. In study 1, I sought to objectively estimate PA in youth with DS using accelerometers and to determine the minimum monitoring days and hours needed. Results indicated that there were significant differences in daily PA between genders and age groups, not between weekdays and weekends, and that overall, 95% of the youth with DS who participated met the national physical activity guidelines. Regarding the minimum monitoring period, the results demonstrated that 4 days and 14 hours of monitoring per day were required to reliably estimate typical PA in youth with DS. In study 2, I aimed to objectively estimate PA using accelerometers and to determine the minimum monitoring days and hours needed in youth with ASD. Results demonstrated that there were significant differences in daily PA between genders and age groups, not between weekdays and weekends, and that approximately 90% of the youth with ASD who participated met the physical activity guidelines. In addition, at least 2 days and 9 hours of monitoring per day were needed to reliably estimate typical PA in youth with ASD. Finally, in study 3, I aimed to compare PA and the minimum monitoring days and hours needed between youth with DS and youth with ASD with the PA data measured on the ankle using accelerometers. Results indicated that placing an accelerometer on the ankle as the monitoring placement appeared to be reliable when measuring PA in youth with DS and ASD. No significant differences were observed for PA between the DS and ASD group, and 3 days of monitoring may be the most reasonable minimum number of monitoring days if both groups are combined into a larger group, categorized as developmental disabilities. However, the minimum monitoring hours appeared to need more investigation to be established.