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Under the best of circumstances, Americans don’t love to work out. Even though movement is among the most accessible and effective ways to improve physical and mental health, federal data show only about 25% of American adults get the government-recommended dose of exercise each week: 150 minutes of moderate or 75 minutes of vigorous aerobic activity, plus two strength-training sessions.

It’s not hard to guess how the COVID-19 pandemic is affecting that number, with its sweeping lockdowns confining millions of Americans to their homes. The data are still coming together, but early reports suggest the pandemic is making Americans more sedentary than ever—and the effects may be long-lasting.

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A preliminary, preprint study posted May 12 on the research publication platform Cambridge Open Engage found that Americans are exercising less than usual during the pandemic, and sitting and looking at screens more. In a sample of about 3,000 U.S. adults, people who were meeting exercise guidelines before the pandemic reported an average 32% reduction in physical activity once social-distancing measures went into effect. Those who were sedentary before tended to stay that way.

But is it really such a big deal to stop exercising for a few weeks or months, especially with so much going on in the world?

Maybe. Study co-author Jacob Meyer, an assistant professor of kinesiology at Iowa State University, says he fears the trend won’t simply reverse itself when life goes back to normal—especially since “normal” may be a long ways off.

“It is incredibly difficult to get somebody who is not already active to become active,” Meyer says. “Now what we’re seeing is people who used to be active are not being active. The question is, will they return to their previous levels of activity?”

Genevieve Dunton, a professor of preventive medicine and psychology at the University of Southern California’s Keck School of Medicine, has concerns as well. She, along with researchers from Colorado State University, is tracking changes in activity among a group of about 800 American adults. Dunton hasn’t done a full analysis yet, but says she can already see marked decreases, especially in steps taken per day.

Fitness-tracker data from Apple, Fitbit, wearables maker Withings and health research firm Evidation bear that out. The exact numbers vary—Withings measured only a 7% average national drop in daily steps, while Evidation put the number at nearly 50%—but they all suggest activity has declined this spring, compared to pre-pandemic conditions.

But the drop hasn’t been felt equally. In some of the country’s less densely populated states—Alaska, Kentucky, Mississippi, New Mexico and West Virginia—step counts have decreased by much less than in urban areas like Washington, D.C., Evidation found. Withings found that daily steps are actually up in some states: by 16% in Indiana, 9% in West Virginia and 4% in Louisiana, for example.

Compared to people in rural areas, city dwellers likely live under stricter stay-at-home measures, and have fewer outdoor exercise options and less space to move inside their homes, says Indika Edirisinghe, an associate professor of food science and nutrition at the Illinois Institute of Technology who is also studying coronavirus-related lifestyle changes.

Federal data also show residents of urban areas are normally more active than people in rural areas, so it makes sense that they would see the largest disruption in routine now. But it’s a mistake to simply assume once-active people will bounce right back to normal once lockdowns lift, Meyer says.

Physical fitness fades surprisingly quickly. It can take as little as a few weeks of inactivity for health markers like oxygen uptake, blood volume and muscle strength to take a hit. It can also take longer to get back in shape than it took to get out of shape. One 2015 study found that it took about six weeks to regain muscle strength after two inactive weeks.

If people are sedentary for months, “there’s going to be a steeper curve to tackle when individuals are restarting, and that’s often the most difficult curve,” Dunton says. “It’s much more unpleasant [to exercise] when you’re unfit.”

Restarting a habit can also be difficult psychologically. Jimikaye Courtney, a doctoral researcher in health and exercise science at Colorado State University who is working with Dunton, is examining how self-efficacy—someone’s belief in their ability to do something—factors into the equation. She says people who score lower on measures of self-efficacy seem likely to both struggle with exercise during the pandemic and find it difficult to resume an exercise regimen after quitting one.

“If they don’t have that internal drive to continue to be active, even if they’re telling themselves they’ll start to be active when this is all over, I don’t know realistically if they’ll be able to do that,” Courtney says.

Compounding that, Meyer’s study found that people who said they’ve scaled back on exercise during the pandemic have also reported poorer mental health than those who maintained a workout regimen.

The pandemic itself is a threat to mental health. Given the rich body of evidence that physical activity can help prevent or improve conditions like depression, Meyer says lack of movement is probably exacerbating the problem. Making matters worse, once mental health begins to dip, it can be extremely difficult to find the motivation to exercise.

For all these reasons, Meyer says he’s concerned about the future of America’s fitness. But Edirisinghe, from the Illinois Institute of Technology, has a more optimistic read on the country’s long-term fitness prospects.

He thinks COVID-19 has hammered home for Americans the importance of good overall health, since many patients who died or got very sick from the virus had underlying health conditions such as diabetes, heart disease and obesity—all of which have a lifestyle component. “That message is going to get into the community,” he says.

The question is whether it’s enough to move the American public.

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Write to Jamie Ducharme at