Objective sleep and physical activity using 24-hour ankle-worn accelerometry among toddlers from low-income families

Poverty is a risk for short sleep duration and limited physical activity. This study describes sleep, physical activity, and sedentary behavior of Women, Infants, and Children-eligible toddlers and the proportion of toddlers meeting recommendations for sleep and physical activity, and examines associations with body mass index z scores and poverty.

A total of 101 toddlers (12-32 months) from low-income families (62% African American) wore 24-hour ankle accelerometers over 3-7 consecutive days. Concurrent validity for daytime napping was assessed using parent-reported toddler wake/sleep between 08:00 and 20:00 collected using Ecological Momentary Assessment. Logistic regressions predicted odds of meeting guidelines.

Toddlers averaged 10.56 hours of sleep in 24 hours. All toddlers averaged ≥180 minutes of total activity per day, 38% had ≥60 minutes of moderate/vigorous physical activity per day, 32% of toddlers slept between 11 and 14 hours over 24 hours, and 26% had a bedtime before 9:00 pm. Body mass index z score was not associated with meeting guidelines. Poverty was associated with less than 60 minutes of moderate/vigorous physical activity.

Most toddlers were not meeting sleep guidelines. This study provides objective data on sleep and activity among a diverse sample of low-income toddlers. Objective measures of sleep and physical activity facilitate surveillance of children meeting guidelines for sleep and physical activity. Such norms are needed to examine disparities among children from varying racial and economic backgrounds. Future research should examine if meeting guidelines is related to other health indicators.