Developmental trends in young children’s device-measured movement behaviour

Background:
Large differences in movement behaviour recommendations exist across childhood. Longitudinal trends in meeting age-specific movement behaviour guidelines are under-researched and limited by methods used to process device-based data.

Purpose:
Using a novel machine-learning approach to process device-based movement data, examine developmental trends and sex differences in movement behaviours in children 2-7 years over a three-year period.

Methods:
Data from the PLAYCE cohort study in W.Australia were analysed (n=1217). Physical activity and sedentary time were measured by accelerometry at ages 2-5 (preschool, wave 1) and 5-7 (full-time school, wave 2), and processed using a validated machine-learning classification model. Daily time spent in sedentary behaviour, energetic play, total physical activity, and meeting physical activity guidelines were analysed using linear and generalised linear mixed-effects models with age-by-sex interactions.

Results:
Behaviours changed significantly (p<0.05) with increasing age and trends were similar in boys and girls. Total physical activity increased from age 2 to 5 then declined to age 7. At all ages, mean total physical activity exceeded the 180 minutes/day guideline. Energetic play increased from age 2 to 7, however, was below 60 minutes/day at all ages except for 7-year-old boys. Sedentary time decreased to age 5 then increased to age 7. All 2-year-old children met the age-specific physical activity guideline, decreasing to 5% of girls and 6% of boys at age 4. At age 7, 46% of boys and 35% of girls met the physical activity guideline.

Conclusions:
Young children’s energetic play and total physical activity increased with age, but few children aged 3-7 met the energetic play guideline.

Practical implications:
Early childhood interventions should focus on increasing energetic play. Strategies are needed to support young children as they transition developmentally and from one movement behaviour guideline to the next.

Funding:
Healthway (#24219, #32925); UKRI-NHMRC Built Environment Prevention Research Scheme [APP1192764].