Correlates of moderate-to-vigorous physical activity among preschoolers during unstructured outdoor play periods

Objective Quantify moderate-to-vigorous physical activity (MVPA) and its correlates in preschool children during outdoor unstructured play periods using direct observation. Methods Cross-sectional data consisting of 204 observation periods collected from 51 four- and five-year-old children using the Observation System for Recording Physical Activity in Children — Preschool (OSRAC-P) at a preschool in southern California, autumn and spring 2009–2010. Gender and BMI classification and OSRAC-P environmental codes were related to observed MVPA in multiple logistic regression models. Results Less than 21% of intervals were spent in MVPA overall. Boys and normal weight children engaged in higher intensity levels than their respective counterparts. More MVPA was associated with normal weight (OR =2.49–3.25, R 2 =3%), location (grass, playground, looping cycle path; OR =3.21–4.90, R 2 =4–12%), play context (ball/objects, wheel, open space; OR =2.78–8.51, R 2 =9%), and group composition (solitary, one-on-one; OR =1.34–2.08, R 2 =1%). Conclusion Open spaces located in playgrounds and grass fields, and activity-genic portable equipment, manipulative objects, and riding vehicles are some design and equipment features that appear to foster MVPA. Lowering play space density and engaging children through teacher prompts and teacher-arranged activities may further increase MVPA on playgrounds.