The spring’s coronavirus stay-at-home orders, and now the cancellation of many summer activities, may aggravate what’s already a difficult season for children when it comes to gaining weight, experts fear.

Studies over the last decade have shown that kids often tend to have stable weight during the school year, but gain weight during summer months. This weight gain is maintained during the school year until another summer — and more pounds — come along.

“As it turns out, with the pandemic, children being at home mimics summer vacations,” said Steven Heymsfield, a professor at the Pennington Biomedical Research Center at Louisiana State University. “They lose the structure of school. Their activities are more limited, they have more screen time, they exercise less, and eat the foods we tell them not to eat.”

The U.S. Census Bureau estimates that 41.9 million youth are ages 10 to 19, and 17% are obese. That’s roughly seven million adolescents, and this number could go up because of the pandemic. What’s more, obesity disproportionately affects African American and Hispanic youths, adding to the many health disparities that the pandemic has highlighted.

When comparing what’s happening during the pandemic to usual school year and summer weight trends, “the prediction is some children will have an increase in their weight and it won’t go back down,” Heymsfield said.

Having all-day access to food is one problem, and even exercise can’t always overcome a bad diet. The other is how the pandemic is shutting down the usual sports and activities that keep many kids active in the summer.

“In a pandemic, we don’t want kids to stop being physically active,” said Matthew Grady, a sports medicine pediatrician at the Children’s Hospital of Philadelphia. “Getting kids active is in their long-term health interests.”

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Experts recommend that school-aged children and adolescents get at least 60 minutes of physical activity each day, but during the pandemic, this has been challenging. According to data released by the fitness tracker Fitbit, younger people are taking fewer steps compared with this time last year, while older people are closer to previous years.

“With organized sports not in full swing, we need to find ways for them to do this so that it’s fun and engaging,” said Naomi Brown, a sports medicine pediatrician at the Children’s Hospital of Philadelphia.

Fun, engaging — and safe.

“As we return to sports, we want to set up a daily monitoring system — lists of people who had contact with each other — that prevents infections from being spread across teams,” Grady said. “And then we can start with the introduction of sports-like activities at the individual level.”

Experts stress that community infection rates of the coronavirus — or the viral burden in the community — will guide how youth sports can resume.

“As we see the community infection rates go down, we can allow the athletes to get closer. Offense teams can practice together. Defense can practice together. Then this can progress to intrasquad scrimmages,” Grady said. “The tricky part about this is if we have a spike in infection, we may have to transition backward. There is a little fluidness, but the goal is to make kids as active as possible without taking risks to get sick.”

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Getting physical activity that is safe during the pandemic is especially difficult for city kids simply because of limited space.

“If you live in an area where social distancing is easy, being active is easier,” Grady said. “If you live in a city with smaller space options, we need policies and procedures that find ways to mitigate potential risks and still keep kids active.”

One such program is the city’s Playstreets program, which for many years has closed streets to vehicle traffic so kids can play and enjoy physical activities.

“We want [kids] to stay active the whole time,” Grady said. “We need to have a community buy-in — providers, educators, and community health people need to be thinking — how to encourage all kids, of all socioeconomic brackets, to engage in physical activity.”