Proceedings of the Nutrition Society

Research Article

Physical activity, sedentary behaviour and energy balance in the preschool child: opportunities for early obesity prevention

Symposium on ‘Behavioural nutrition and energy balance in the young'

on 27 and 28 March 2008, A Meeting of the Nutrition Society, was held at the West Park Conference Centre, Dundee, hosted by the Scottish Section.

John J. Reillya1 c1

a1 University of Glasgow Division of Developmental Medicine, 1st Floor Tower Block QMH, Yorkhill Hospitals' Glasgow G3 8SJ, UK


Prevalence of obesity in preschool children has increased dramatically in recent years. The preschool years (age 3–6 years) have been regarded as critical for the programming of energy balance, via the concept of early ‘adiposity rebound’. Children who undergo early adiposity rebound are at increased risk of later obesity. Recent evidence suggests that associations between timing of adiposity rebound and later obesity may not reflect programming, but might denote that ‘obesogenic’ growth trajectories are often established by the preschool period. Studies of objectively-measured physical activity and sedentary behaviour in preschool children show that levels of physical activity are typically low and sedentary behaviour high. The review of evidence presented here is supportive of the hypothesis that physical activity is protective against obesity in the preschool period, and that sedentary behaviour, particularly television viewing, is obesogenic. Definitive evidence on dose–response relationships between physical activity, sedentary behaviour and obesity remain unclear. Dose–response evidence could be obtained fairly readily by intervention and longitudinal observational studies that use accelerometry in preschool children. The generalisability of much of the evidence base is limited and there is a need for research on the influence of physical activity and sedentary behaviour in the preschool years in the aetiology of obesity in the developing world.


c1 Corresponding author: Professor John J. Reilly, fax +44 141 201 0710, email