One hour of activity needed to offset harmful effects of sitting at a desk - Philippa Lynch

Risk of dying increases among desk-based workers who sit for eight hours and do low amounts of exercise, new research finds - link to Guardian article

At least an hour of physical activity a day may be required to offset  for eight hours, according to the latest study to highlight the perils of a sedentary lifestyle.

The World Health Organisation (WHO) guideline, adopted by Public Health England, recommends 150 minutes of exercise a week but research, based on data from more than one million people, suggests that is insufficient for many. A team of international experts found that the risk of dying during a follow-up period of two to 18 years was 9.9% for those who sat for eight or more hours a day and engaged in low activity, compared with 6.8% for those who sat for less than four hours a day and were active for at least one hour a day. But they also found that the increased risk of death associated with sitting for eight hours a day was eliminated for people who did a minimum of one hour of physical activity a day.

Lead author Prof Ulf Ekelund, from the Norwegian School of Sports Sciences and Cambridge University, said: “You don’t need to do sport, you don’t need to go to the gym. It’s OK doing some brisk walking, maybe in the morning, during lunchtime, after dinner in the evening. You can split it up over the day, but you need to do at least one hour.

“It’s not easy to do one hour of physical activity a day but ... the average TV viewing time in adults in the UK today is 3hrs 6mins or something like that, more than three hours. I don’t know if it’s too much to ask that just a little bit of those three hours may be devoted to physical activity.”

Ekelund also said a five-minute break at work every hour, even to go to the printer, would be beneficial and said it was in employers’ interests to facilitate culture change.

A WHO spokesman said: “Recommendations related to sitting and sedentary behaviours are not available yet. However, WHO already recommends governments implement policy actions around making environments where people live and work more conducive to physical activity".

“People who sit for longer hours should be concerned and could take the findings of this research as an opportunity to be proactive.”