Time spent being sedentary: an emerging risk factor for poor health

SEDENTARY TIME IS AN INDEPENDENT RISK FACTOR FOR DISEASE

Sedentary time (ST), or time being physically inactive, is an important risk factor for all-cause mortality and a range of diseases including cardiovascular disease and cancer.¹ It has a global impact on mortality comparable with tobacco use and obesity.² Moreover, high volumes of intensive activity only attenuate, and do not reduce, the risk posed by ST.³ Replacing ST with light physical activity (PA) leads to improvements in insulin sensitivity and plasma lipid profiles that are not replicated by simply adding bouts of moderate or vigorous physical activity to a sedentary lifestyle,⁴ indicating that being sedentary may trigger a distinct disease process.

The UK has high rates of physical inactivity and performs poorly when compared internationally. Approximately 25% of adults achieve <30 minutes of PA a week, and 80% of children under 15 years are not meeting current PA recommendations in the UK.⁵ The causes are multifactorial, including societal and political drivers. ST is a disease of public health and primary care importance, and primary care clinicians have a key role in educating and guiding individuals at both primary and secondary prevention levels. Unfortunately, recent evidence suggests that there is poor awareness of the availability and use of physical activity guidance in primary care.⁶

Additionally, there is little current understanding as to what constitutes ‘being sedentary’ and of the mechanisms by which physical activity or inactivity impact on health and disease.

UNDERSTANDING SEDENTARY TIME

Increasing our …