Sedentary behaviour - a risk factor in itself

Perhaps the question we’re asked the most is, ‘why is there a requirement in the Active Practice Charter to reduce sedentary behaviour as well as increase physical activity – surely they’re one and the same?’ 

Sedentary behaviour and inactivity are linked – but the science, and the national guidelines, encourage us to think about them as separate and additive risk factors. Breaking up long periods of sitting down is particularly relevant for those of us who work long hours in an office, over and above getting your daily ‘dose’ of physical activity, hence its presence in the Active Practice Charter. Over to Dr Richard Mayne, an academic GP with an interest in sedentary behaviour, to explain more in the next section.

Why does sedentary behaviour matter?

Humans were not made to sit behind desks. We were made to move. Did you know there is a dose-response relationship between sedentary time and mortality? Unfortunately, the more time we spend being sedentary, the higher our risk of death – it is a separate and additive risk factor to being less active.

The effect of sedentary behaviour (sitting or lying in a state of low energy expenditure) on mortality was first discovered by the epidemiologist Jeremy Morris in post-World War Two London. Morris and his colleagues found that (sedentary) bus drivers had higher rates of mortality from cardiovascular disease than their (physically active) bus conductor colleagues. The main reason for this was postulated to be due to their differences in sedentary behaviour and physical activity during the working day, as they had very similar lifestyles outside of work. 

Scary reading for us GPs at the coalface of the NHS, working behind desks all day long! Are we the sedentary bus drivers compared to our more physically active, bus conductor hospital colleagues?

Many working adults in the UK spend 9 hours or more sitting down every day. Children and retired people from lower socioeconomic groups are more likely to be sedentary compared to their better off counterparts, as well as those who already have a chronic condition. As primary care practitioners, looking out for this prevalent risk factor and providing advice and aspiration – particularly in these groups – could have powerful consequences.