We all know that a sedentary, office-based lifestyle – slumped in a wheely chair for eight hours a day, give or take a lunchtime dash to Pret – isn’t what nature intended for human beings. Vaguely, we’re aware that it can’t be healthy, exactly.
But according to a startling new study, sitting down all day with little exercise could actually be what kills us.
The study, conducted by a team of international health experts, analysed data from more than one million people, the Guardian reports. It found that people who sat for eight or more hours a day and did little exercise had a 9.9% chance of dying during a follow-up period of two to 18 years. For people who sat for less than four hours and were active for at least one hour a day, the risk of dying during that period dropped to 6.8%.
However, they also found that people who sat for eight hours a day and managed to squeeze in an hour of physical activity saw their increased risk of death totally eliminated. And – reassuringly for those of us who don’t want to die young because we couldn’t fit in a Zumba class – that hour of exercise doesn’t have to be anything too demanding.
“You don’t need to do sport, you don’t need to go to the gym,” said Professor Ulf Ekelund from Cambridge University and the Norwegian School of Sports Sciences, the lead author on the study. “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.”
The paper, published in the Lancet, analysed data from 16 studies, mainly involving people aged over 45 from western Europe, Australia and the US. It found that one hour of “moderate intensity” exercise – for example, walking at 5.6 km/h or cycling for pleasure at 16 km/h – was enough to cancel out the health risks of sitting for long periods.
Although Ekelund acknowledged that a busy work schedule can make fitting in an hour of exercise every day seem like an impossible task, he also pointed out that most people do have some free time on their hands.
“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 three hours six minutes or something like that, more than three hours,” he said. (He's underestimating our love of telly: the average Brit actually watches three hours and 40 minutes of TV a day.) “I don’t know if it’s too much to ask that just a little bit more of those three hours may be devoted to physical activity.”
The World Health Organisation and Public Health England already recommend at least 150 minutes of exercise a week, and Ekelund is far from the first person to highlight the dangers of a sedentary lifestyle.
Individuals who spend more than six hours a day in their chair are at an increased long-term risk of diabetes, back pain, cardiovascular diseases and cancer – specifically ‘female’ cancers linked to body fat and oestrogen levels. Nilofer Merchant, a former CEO who lectures on innovation and board governance at Stanford University, has called sitting “the smoking of our generation”. He recommends that colleagues take a walk together rather than hold sitting-down meetings, as a way of “resolv[ing] the tradeoff between ‘taking care of health’ and ‘getting stuff done’.”
Now, if you don’t mind – we’re just popping out for a stroll…