Researchers say people who sit down a lot must exercise for one hour a day. This is so they live longer. Doctors keep telling us that sitting down a lot makes our life shorter. Sitting in a chair all day is as dangerous as smoking or being overweight. Sitting for eight hours increases the risk of dying early by 60 per cent. However, there is good news. One hour's exercise each day can cancel the risk of dying early from sitting all day.

The research was published in time for the Olympic Games. Researchers hope this will get people to exercise more. Watching TV all day is very unhealthy because we will also eat unhealthy snacks. No exercise increases the risk of heart disease, diabetes and cancer. People should get out of their seat more. A researcher advised people to take breaks every hour, or to walk upstairs. He added: "Build physical activity into your everyday life."