The researchers now pulled information from 4840 participants of different ethnicities, male and female, who ranged in age from 40 to 85. All had joined the survey between 2003 and 2006 and worn an activity monitor for a week. Based on that data, the researchers grouped people according to how many minutes they walked or otherwise moved most days. They also checked people’s names against a national death registry to establish mortality risks for the various activity levels.

Using those results, they began creating a series of statistical what-ifs. Suppose, the researchers asked, everyone who was capable of exercising began exercising moderately, such as by walking briskly, for an extra 10 minutes per day, on top of how much or little they currently worked out? How many deaths might not happen?

The researchers made adjustments to account statistically for those people who were too frail or otherwise unable to walk or easily move around. They also considered age, education, smoking status, diet, body mass index and other health factors in their calculations.

Then, the researchers ran the same statistical scenario with everyone working out for an extra 20 minutes a day and, finally, for an extra 30 minutes a day and checked the mortality outcomes.

Quite a few people would live longer in any of those scenarios, they found. According to the modelling, if every capable adult walked briskly or otherwise exercised for an additional 10 minutes a day, 111,174 deaths annually across the country – or about 7 per cent of all deaths in a typical year – might be avoided.

When they doubled the imagined exercise time to an extra 20 minutes a day, the number of potentially averted deaths rose to 209,459. Tripling the exercise to 30 extra minutes a day averted 272,297 deaths, or almost 17 per cent of typical annual totals. (The data was gathered before the pandemic, which has skewed mortality numbers.)

Those figures might seem abstract, but, in practice, those hundreds of thousands of deaths forestalled could turn out to be deeply personal. They could mean avoiding the early death of a spouse, parent, friend, grown child, co-worker or, of course, us, said Pedro Saint-Maurice, a public health researcher at the National Cancer Institute, who led the new study.

“There is a message in this data for public health entities” about the importance of promoting physical activity to reduce premature deaths, he said. And the message applies equally to each of us.

So get up and walk or engage in some kind of moderate physical activity for an extra 10 minutes today. Invite your friends, colleagues and ageing parents to do the same. “In this context, a little additional physical activity can have a huge impact,” Saint-Maurice said.

This article originally appeared in The New York Times.

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