Shade coverage, ultraviolet radiation and children's physical activity in early childhood education and care.

To investigate the association between shade coverage in early childhood education and care (ECEC) centres and pre-school children's physical activity, outdoor time and ultraviolet radiation (UVR) exposure.A total of 48 ECEC centres (678 children) in the Western Australian Play Spaces and Environments for Children's Physical Activity (PLAYCE) study took part. Physical activity at ECEC was measured using 7-day accelerometry. UVR exposure was measured using polysulphone film attached to children's shoulders. Educators reported time spent outdoors. The Shade Factor and remote sensing imagery captured shade coverage.Centre vegetation but not Shade Factor was significantly negatively associated with children's UVR exposure (p < 0.001). Higher levels of vegetation were associated with increased time outdoors, but higher levels of the Shade Factor were associated with decreased time outdoors (all p < 0.001). Neither shade measure was significantly associated with physical activity. Outdoor time moderated the relationships between shade measures, physical activity and UVR exposure.The provision of shade, particularly through natural forms such as tree canopy, is an important sun protection strategy and enabler of outdoor time in children attending ECEC.