Background/Aims: 24-hour movement guidelines promote a healthy balance of high levels of physical activity, low levels of sedentary behaviour and sufficient sleep each day. At present, surveillance data on how Australian adolescents are performing against these guidelines are lacking. The present study aimed to provide current population estimates of adherence to the physical activity, screen time and sleep duration recommendations outlined in the national 24-hour movement guidelines, both individually and in combination, and investigate whether compliance levels varied according to socio-demographic factors. Trends over time were also assessed to determine if there have been significant changes in these behaviours over the past decade.
Methods: National cross-sectional surveys of students in year levels 8 to 11 (ages 12-17 years) were conducted in 2009-10 (n=13,790), 2012-13 (n=10,309) and 2018 (n=9,102) using validated instruments administered via a self-report web-based questionnaire. Prevalence estimates were calculated using weighted data adjusted for the clustering of students within each school.
Results: Only 2% of students surveyed in 2018 met all three key recommendations outlined in the 24-hour movement guidelines. Adherence to the sleep duration recommendation was highest (67%) with substantially smaller proportions meeting the physical activity (16%) and screen time (10%) recommendations. Females were less likely than males to report meeting recommended levels of physical activity, while older adolescents were less compliant with both the physical activity and screen time recommendations. Students’ adherence to the screen time recommendation has halved since 2009-10 (19%), whereas there has been no change in the proportion meeting the physical activity and sleep duration recommendations.
Conclusions: Findings underscore the need for policy proposals and environmental interventions to better support all Australian adolescents in meeting the 24-hour movement guidelines, with particular focus on strategies to assist in the reallocation of sedentary screen time to physical activity.