Office workers must exercise for an hour a day to counter death risk
Irish workers, who have sedentary jobs, may eliminate some of the harmful effects of sitting if they do one hour of physical activity daily, new research reveals.
The findings, in the 'Lancet', which are part of a series measuring global levels of physical activity since the last Olympics, also warn that lack of exercise is linked to one in 20 cases of dementia in Ireland.
Physical inactivity is associated with an increased risk of heart disease, diabetes and some cancers, leading to around five million deaths across the world annually.
Scientists said sedentary lifestyles were now posing as great a threat to public health as smoking, and were causing more deaths than obesity.
As more employees have no choice but to spend eight or more hours a day sitting down, the risks are on the rise.
However, the study from the University of Cambridge in the UK and the Norwegian School of Sports Sciences, which looked at over one million people, said one hour of exercise such as a brisk walk or cycling for pleasure may eliminate the increased risk of death associated with prolonged sitting.
Most of us will spend hours on the couch watching the world's fittest athletes during TV coverage of the Olympics, which begin in Brazil next week.
But since the last Games four years ago there has been little progress in increasing levels of physical activity.
Around one in four adults globally and 80pc of school-going teenagers are failing to meet the World Health Organisation recommendation of 150 minutes of moderate-intensity exercise per week.
Physical activity is a valuable part of any overall body wellness plan and is associated with a lower risk of brain decline.
In order to reduce the risk of dementia, we should engage in cardiovascular exercise to elevate the heart rate.
This increases the blood flow to the brain and body.
It reduces potential dementia risk factors such as high blood pressure, diabetes and high cholesterol.
The researchers also looked at time spent watching television all day and found sitting for over three hours looking at the goggle-box was associated with increased risk of death, except in the most active.
The authors said: "For many people who commute to work and have office-based jobs there is no way to escape sitting for prolonged periods of time.
"For these people in particular, we cannot stress enough the importance of getting exercise, whether it is getting out for a walk at lunchtime, going for a run in the morning or cycling to work.
"An hour of physical activity per day is the ideal, but if this is unmanageable, then at least doing some exercise each day can help reduce the risk."
Overall, the 'Lancet' reported that while in the past four years more countries have been monitoring progress in physical activity, the evidence of improvements is scarce.
Earlier this year, Ireland launched its first National Physical Activity Plan, with the aim of increasing the number of people taking regular exercise by 50,000 a year over the next decade. Seven out of 10 adults are too inactive and fail to get the necessary 30 minutes a day of moderate activity five days a week, which is recommended for 18- to 64-year-olds.
The plan involves supporting more community walking groups, getting doctors to prescribe exercise for patients and encouraging employers to bring in standing desks to avoid staff having to sit all day.
The plan, which comes with €5.5m funding, also involves introducing a new school subject, Well-being, from September as part of the new Junior Cycle.
This subject will include physical education.