The Descriptive Epidemiology of Sedentary Behaviour

There is an interest in monitoring increases in sedentary time globally, although recent European data does not show such a trend. New norms due to the COVID-19 pandemic may influence both total sitting time and domain-specific sitting time. Also, recent evidence on the interplay between sedentary behaviour and physical activity has identified the joint association of ‘high sitting-low active’ as a risk indicator and not just high sitting time. This chapter summarises recent evidence on the prevalence of sedentary behaviour among different age groups, comprising 50 large and population-representative studies for adults, 7 studies for older adults and 26 studies for children and adolescents, published between 2012 and 2021. Furthermore, this chapter describes the correlates of sedentary behaviour for adults, older adults and children and adolescents derived from large population-based cross-sectional studies. Among adults the median total sitting time was 6.4 h/day. Self-reported sedentary time was 5.6 h/day which was more than 2½ h/day less than that observed from device-based measured sitting time (median 8.3 h/day). Reported television (TV) watching time showed a median of 2.2 h/day. The median prevalence of sedentary behaviours among older adults (6.7 h/day) was higher than among adults (6.4 h/day), especially measured TV time (3.2 h/day vs. 2.3 h/day). For children and adolescents, the total median sedentary time was 7.5 h/day and increased from early childhood through adolescence. The median screen time was 2.9 h/day. Overall, no differences in the prevalence estimates were observed in studies from 2016 and onwards compared to previous studies.