Why we should sit less
There is increasing evidence that, unless you are a wheelchair user, sitting down too much can be a risk to your health.
To reduce our risk of ill health from inactivity, we are advised to exercise regularly, at least 150 minutes a week, and reduce sitting time.
Studies have linked being inactive with being overweight and obese, type 2 diabetes, some types of cancer, and early death.
Sitting for long periods is thought to slow the metabolism, which affects the body's ability to regulate blood sugar, blood pressure and break down body fat.
Many adults in the UK spend around nine hours a day sitting. This includes watching TV, using a computer, reading, doing homework, travelling by car, bus or train but does not include sleeping.
Move more, sit less
The UK Chief Medical Officers' Physical Activity Guidelines report on GOV.UK recommends breaking up long periods of sitting time with at least light activity.
However, there is currently not enough evidence to set a time limit on how much time people should sit each day.
Nevertheless, some countries – such as Australia – have made recommendations that children limit screen time, such as TV and video games, to one to two hours a day. This is to reduce the time spent sitting.
Bus drivers and astronauts
The link between illness and sitting first emerged in the 1950s, when researchers found double decker bus drivers were twice as likely to have heart attacks as their bus conductor colleagues. The drivers sat for 90 per cent of their shifts, the conductors climbed about 600 stairs each working day.
It is thought excessive sitting slows the metabolism – which affects our ability to regulate blood sugar and blood pressure, and metabolise fat – and may cause weaker muscles and bones.
Research on astronauts in the early 1970s found life in zero gravity was linked with accelerated bone and muscle loss and ageing.
Adults
Adults aged 19 to 64 are advised to try to sit down less throughout the day, including at work, when travelling and at home.
Tips to reduce sitting time:
stand on the train or bus
take the stairs and walk up escalators
set a reminder to get up every 30 minutes
place a laptop on a box or similar to work standing
stand or walk around while on the phone
take a walk break every time you take a coffee or tea break
walk to a colleague's desk instead of emailing or calling
swap some TV time for more active tasks or hobbies
Find out about physical activity guidelines for adults aged 19 to 64
Older people
Some older people (aged 65 and over) are known to spend 9 hours or more each day sitting.
Tips to reduce sitting time:
avoid long periods sat in front of a TV or computer
stand up and move during TV advert breaks
stand or walk while on the phone
use the stairs as much as possible
take up active hobbies such as gardening and DIY
join in community-based activities, such as dance classes and walking groups
take up active play with grandchildren, if you have them
do most types of housework
A modern problem
People are less active nowadays, partly because technology has made our lives easier. We drive cars or take public transport. Machines wash our clothes. We entertain ourselves in front of a TV or computer screen.
Fewer people are doing manual work, and most of us have jobs that involve little physical effort. Work, household chores, shopping and other necessary activities are far less demanding than for previous generations.
We move around less and burn off less energy than people used to. Research suggests that many adults spend more than seven hours a day sitting down, at work, on transport or in their leisure time. People aged over 65 spend ten hours or more each day sitting or lying down, making them the most sedentary age group.
Sedentary lifestyles
Inactivity is described by the Department of Health and Social Care as a "silent killer". Evidence is emerging that sedentary behaviour, such as sitting or lying down for long periods, is bad for your health.
Not only should you try to raise your activity levels, but you should also reduce the amount of time you and your family spend sitting down.
Common examples of sedentary behaviour include watching TV, using a computer, using the car for short journeys and sitting down to read, talk or listen to music. This type of behaviour is thought to increase your risk of developing many long-term conditions, such as heart disease, stroke and type 2 diabetes, as well as weight gain and obesity.
Crucially, you can hit your weekly activity target but still be at risk of ill health if you spend the rest of the time sitting or lying down.
For a summary on the health benefits of being more active, see the physical activity guidelines from the Department of Health and Social Care.