Sitting down for more than seven-and-a-half hours a day increases the risk of dying young, a study has claimed.
Staying in chairs during the working day and on the sofa in the evening is linked to a host of health problems.
The likelihood of dying early increases gradually when spending 7.5 to 9 hours per day sitting, researchers found.
The threat increases more steeply after 9.5 hours of sitting per day.
Those spending 12 hours per day sitting down had nearly three times the chance of dying early compared to those who sat for 7.5 hours per day.
Experts at Leicester University who reviewed of evidence from 10 international studies found sitting duration has increased since lockdown.
Kneeling or sitting on flat surfaces means continuous low-level use of a number of muscle groups.
Author Dr Charlotte Edwardson said people who sit a lot need 30 to 75 minutes of moderate to vigorous exercise each day to undo the damage caused by their sitting.
She said: “We know that many people cannot fit this level of physical activity into their daily lives.
“But what we can do is break up long bouts of sitting with light activity, such as standing during work meetings or phone calls, walking around the office or house or doing simple arm exercises or calf raises.”
To mark On Your Feet Britain Day today, the team is urging workers to take part in its free SMART Work programme, which prompts people to get out of their chair more regularly.