Experts have found that people who sit for long periods - such as office workers - are at risk of an early death.

However, they also claimed that taking just 22 minutes a day to brisk walking, do housework or jog, can offset the negative health effects of too much sitting down.

Moderate-to-vigorous physical activity (MVPA) eliminates all the bad benefits of sitting down for too long.

The study backs up the UK chief medical officers’ recommendation that people aim for 150 minutes of MVPA per week – roughly 21 minutes per day.

Examples of moderate activity include very brisk walking (4mph or faster), heavy cleaning such as washing windows or mopping, cycling at 10-12mph, or badminton.

Vigorous activity includes hiking, jogging at 6mph or faster, shovelling, fast cycling, a football game, basketball or tennis.

In the UK, guidelines say: “For good physical and mental health, adults should aim to be physically active every day. Any activity is better than none, and more is better still.”

In the new study, published online in the British Journal of Sports Medicine, experts examined data for 11,989 people aged over 50, half of whom where women, from Norway, Sweden and the US.

"Every minute higher MVPA showed a lower risk of death"

People in the study had worn activity trackers which measured their MPVA.

In all, 5,943 people spent fewer than 10.5 hours sitting down every day while 6,042 spent 10.5 or more hours being sedentary.

Over a five-year follow-up, 6.7% (805) of the people died.

The research showed MPVA for 22 minutes each day offset the negative effects of being sedentary and eliminated the risk of dying early due to prolonged sitting down.

Author Edvard Sagelv, from the Arctic University of Norway, told the PA news agency: “In our study, we found that only those people doing more than 12 hours per day sitting had a higher risk of death.

“We are talking about any sitting behaviour – such as being in the office or watching TV for long periods of time.

“In our study, every minute higher MVPA showed a lower risk of death – meaning if people were doing less than 22 minutes (such as 10 minutes) there was still a lower risk of death.

“However, doing 22 minutes eliminated the higher risk of death from sedentary time.

“This means that if doing 22 minutes or more per day, there was no excess risk from sedentary time.

“And, if doing more than 22 minutes per day, there was a lower risk of death overall. Basically, the more the better.”

The overall research team concluded: “Efforts to promote physical activity may have substantial health benefits for individuals and small amounts of MVPA may be an effective strategy to ameliorate mortality risk associated with high sedentary time.”

'There are some simple tips that can help to spend less time sitting down'

Regina Giblin, senior cardiac nurse at the British Heart Foundation, said: “This research supports previous findings that show the negative effects of long periods sitting down and the positive impact of exercise.

“It’s previously been shown that being sedentary for long periods increases the risk of heart and circulatory disease.

“There are some simple tips that can help to spend less time sitting down.

“Walking away from your computer screen at regular intervals, going for a walk or cooking a healthy meal from scratch are ways to incorporate active time into your day.

“Being active can help you control your weight, reduce your blood pressure and improve your mental health.”