Correlates of Toddlers' Physical Activity Levels and Sedentary Behavior During Unstructured Outdoor Play in Early Childhood Education and Daycare Settings.

Despite recent research showing that early childhood education and daycare settings (ECEC) have an important role in promoting toddlers' physical activity (PA), crucial information gaps remain regarding toddlers' PA and sedentary behavior (SB) in these outdoor settings. We aimed in this study to: (a) analyze PA patterns and SB during unstructured outdoor play time in preschool and daycare environments using accelerometry and systematic observation; (b) provide concurrent accelerometry and observational data to help validate the Observational System for Recording Physical Activity in Children-Preschool Version (OSRAC-P); and (c) examine individual, social and environmental correlates of PA and SB during toddlers' unstructured outdoor play time. We found that: (a) toddlers displayed high amounts of PA with no sex, BMI, and/or age differences in PA and SB levels,; (b) environmental variables (e.g., fixed equipment and playground density) were not associated with PA levels or SB intensity; (c) the OSRAC-P was a reliable and valid means of observing and analyzing toddlers' PA patterns during unstructured outdoor play time; and (e) different social patterns between boys and girls did not impact PA levels or patterns. Combining different measurement methods permitted an improved understanding of unstructured outdoor play in preschool and daycare settings.