Sitting and moving

About this video

Count the sitting in an ordinary day: breakfast, the bus or car, a desk at school or work, lunch, the trip home, dinner, then a film or a phone on the sofa. Many hours can go by without standing. Does all that sitting matter if you also go for a run?

Sedentary time is time awake when you sit, recline or lie down and use very little energy: watching TV, reading, driving, sitting at a desk. Sleep doesn't count; the body needs it. Studies that followed people for years found more sedentary time linked to poorer health: in adults, a higher risk of dying early and of dying from heart disease or cancer; in children and teenagers, poorer heart health, more body fat and shorter sleep. These studies watched people rather than testing them, so they show links, not proof of cause, and the World Health Organization says there isn't yet enough evidence to name a safe number of hours.

Can activity make up for sitting? In 2016 a team led by Ulf Ekelund put together 16 studies of more than one million people. People who sat for more than 8 hours a day had a higher risk of dying early if they were not very active. But people who sat just as long and were also active for about 60 to 75 minutes a day, for example brisk walking or cycling, had no extra risk from all that sitting. The researchers concluded that not being active is a greater health risk than sitting for long. Watching a lot of TV was a little different: being very active made its extra risk smaller, but didn't take all of it away.

An hour or more a day is a lot, and only about 1 in 4 people in those studies did that much, so the advice has two parts: be active, and sit less. WHO's advice is to replace sitting with activity of any kind, since even light activity, like standing up and walking about, brings benefits. Get up every so often, walk while you talk on the phone, and on days of long sitting try to fit in about an hour of moderate activity. This video explains sedentary time, from the lesson Sitting Too Long on Knaph.

Transcript

1. 0:00Breakfast, the bus, a desk, lunch, the trip home, dinner, the sofa. Hours of sitting. Does it matter if you also go for a run?
2. 0:10Sedentary time is sitting, reclining or lying while awake, using very little energy. TV, reading, driving, a desk. Sleep doesn't count.
3. 0:22More of it is linked to dying early, and to heart disease and cancer in adults. In the young, to poorer heart health, more body fat and shorter sleep. These are links, not proof, and no safe number of hours is known.
4. 0:39A study of over a million people. Those who sat more than eight hours a day and weren't very active had a higher risk of dying early. But those who sat as long and were active for about an hour a day had no extra risk from the sitting. TV was different. Activity shrank its risk, but didn't remove it.
5. 1:04Not being active is the bigger risk. But only about one in four did that hour. So, be active, and sit less.
6. 1:16Break up long sits. Get up and move every so often. Walk while you talk on the phone. On long sitting days, fit in about an hour of moderate activity.
7. 1:30Move enough every day, and get up often.