Sitting is the new smoking is the mantra of health gurus and standing desk enthusiasts worldwide (including Apple CEO Tim Cook, who used it during 2015’s Apple Watch reveal) but for Britons emerging from lockdown restrictions it may sound like a curse. Despite the boom in running and online workouts, overall the nation’s physical activity dropped by roughly a third during the pandemic. And with some amount of home working set to remain a part of many lives, are we all effectively smokers now? I asked Dylan Thompson, professor of human physiology at the University of Bath.

I don’t smoke, but I sprinted for a bus while commuting and my breathlessness definitely had a ‘20-a-day’ vibe. Have I Netflix‑and‑chilled myself ill?
I don’t believe that sitting is the new smoking, if that’s what you’re asking. It might be a nice way to try to convey that sitting is associated with health risks, but it’s not comparable. The damage caused by smoking can’t be offset. But a moderate level of physical activity can offset high levels of sitting. Even just a little bit can do powerful things: one of our studies found that two minutes of light activity every half hour will keep your blood glucose concentrations at a normal level.

That’s a relief. It feels like everything fun is bad these days and I do love a good sit. Just how risky is it?
If you spend long periods sitting, then you can’t dispose of the glucose in the food that you’re eating. It accumulates in your blood and increases the risk of diabetes. You can’t remove the lipids in the fat from your blood after eating a meal, and that will put you at high risk of cardiovascular disease, heart disease and stroke.

Weird to think of sitting in an office as especially dangerous, although I always said that Microsoft Excel would kill me. Is this just an office worker problem?
Not really – we’ve engineered a lot of physical activity out of our lives across many demographics, workplaces, and in leisure time. Social media, iPhones – these things might not be designed to be used while sitting but it’s what happens. We’ve done research and even in schools, the children are spending only a tiny fraction of their day engaged in physical activity. The rest of the time they are sitting.

Work is so all-consuming these days. British employees are some of the most stressed in Europe. If work culture is making us sick, shouldn’t we change work culture?
I think it’s reasonable for people to focus on reducing sitting. It will almost certainly make them more physically healthy, and contribute to mental health as well. It’s just about finding effective ways to avoid sitting. Sometimes I do walking meetings.

You were involved in setting the physical activity guidelines with the chief medical officer in 2018, which prescribed 150 minutes of exercise a week. In light of home working, should we be doing more?
Back then, we didn’t have a firm consensus on how much physical activity was required to offset the impact of too much sitting. We still don’t. We do know that one of the biggest risk factors for ill health is unemployment. People have suggested that’s because people stay at home and don’t have the incidental activity associated with getting up, commuting etc. But I imagine it’s highly individual.

On that note, I think it’s high time I took a walk. Thank you, Dylan!
Sounds good, bye now!