Generation Sedentary - Understanding the role of sedentary and activity for obesity and non-communicable disease prevention in youth

"Generation Sedentary" aims to understand the amount and levels of physical activity and sedentary time in youth. We also aim to understand how physical activity and sedentary time are associated with obesity and cardio-vascular risk markers in youth. During the period spanning 01.10 2020 to 01.05 2021 we have published six peer review papers directly relevant for the project. Above all, we published data on the temporal trends in device measured physical activity and sedentary time spanning a period of more than 10 years in Norwegian youth. Our research has also continued to contribute to advancing our understanding of the associations between sedentary time and physical activity with metabolic heath in youth. In total, we have published 57 peer-reviewed articles since the start of the project.

Science directly related to Generation Sedentary have informed public health policy in terms of the recently published World Health Organization 2020 guidelines on physical activity and sedentary behaviour. Further, we have contributed to updating the Swedish physical activity guidelines and lead the expert group in Norway also updating the guidelines.

Recent decades have seen considerable societal changes globally. Among the most profound changes are the remarkable increases in electronic media use including mobile phones, internet and online and video gaming. These changes in the availability of sedentary forms of entertainment have influenced on the behaviour of young people and available data suggest that contemporary youth spend a considerable amount of their awake sedentary. This behaviour likey track into adulthood and then constitute a substantial public health problem as inactivity is a major risk factor for premature mortality. Our previous research have suggested associations between early life factors such as birth weight and rapid infancy weight gain, sedentary behaviours and physical activity with overweight, obesity and an adverse metabolic profile also in otherwise healthy young people. However, little is known about the partly modifiable early life determinants of sedentary time and physical activity. In particular, it is unknown whether maternal and early life factors, such as gestational age, birth weight, rapid weight gain in early life, early motor development and infant temperament act as determinants of later sedentary time and physical activity. It is also unclear whether physical activity may modify the associations between early life factors and childhood obesity and metabolic risk markers for non-communicable diseases; and whether these associations differ between youths from developed and developing countries. Finally, the magnitude and direction of associations and detailed dose-response relationships between sedentary time and physical activity with obesity and non-communicable disease risk markers are yet to be clarified in young people. The combined evidence from this research programme will inform future intervention strategies for primary prevention of obesity and non-communicable diseases in young people and inform public health guidelines, policies and programs in new ways.