Physical Activity Participation By Intensity & Time Of Day Among Children

Physical Activity (PA) is essential for development, yet the time of day for effective pediatric interventions is unknown. PA behavior varies across the day due to environmental context and circadian rhythm. Identifying periods of high likelihood of PA participation can provide an opportunity to reduce barriers to meeting the PA guidelines by intervening at those time periods. Through community-based research, we explore times for intervention with a high likelihood of health-enhancing PA in central Texas. PURPOSE: To determine daily PA patterns in children as a way to facilitate meeting the PA guidelines. METHODS: Children (n = 33, 45% female, 60% Hispanic) mean age 5.7 ± 2.2, wore accelerometers for 72 hours. Data were reduced using standard actigraphy software. Waking hours of the daily 24-hour cycle were grouped as waketime, morning, midday, afternoon, evening, and night. Comparisons of MVPA duration and rate as steps per minute across the time of day were done using repeated measures ANOVA with Bonferroni post hoc correction. RESULTS: Only 36% of the sample met the daily PA guidelines. MVPA duration was significantly greater in the evening than at any other time of day. There was no significant difference in MVPA duration from morning through afternoon (17.49 evening vs. 13.53, 15.0, 14.9 min, p<0.001). Rate was significantly greater during evening hours compared to morning and midday (27.71 evening vs. 22.12, 21.23 steps/min, p<0.05), but not in the afternoon. Waketime and night hours were not significantly different from each other in either measure but were lower than all other groups. CONCLUSION: Children’s PA remains below the recommended guidelines. The late afternoon/evening hours present an opportunity to approach PA guidelines as longer and more intense PA is common during that time for children in Central Texas. Schools and caregivers should also promote MVPA during morning hours to break up periods of sedentary behaviors. UT Austin Vice President's Office for Research, Scholarship, and Creative Endeavors