until recently, running was a major part of Emma Zimmerman’s life. The 26-year-old freelance journalist and graduate student was a competitive distance runner in college and, even after she graduated, she logged about 50 miles per week. So she tentatively tried to return to her running routine roughly a week after a probable case of COVID-19 in March, doing her best to overcome the malaise that followed her initial allergy-like symptoms. Each time, though, “I’d be stuck in bed for days with a severe level of crippling fatigue,” Zimmerman says.
Months later, Zimmerman still experiences health issues including exhaustion, migraines, brain fog, nausea, numbness, and sensitivity to screens—a constellation of symptoms that led doctors to diagnose her with Long COVID. Though she can’t know for sure, she fears those workouts early in her recovery process may have worsened her condition.
“I had no idea that I should try to rest as hard as I needed to rest,” she says.
Stories like Zimmernan’s—illness, improvement, exercise, crash—are common in the Long COVID world. And they highlight what many researchers, patients, and advocates say is one of the most powerful tools for managing, and potentially even preventing, Long COVID: rest.
The only guaranteed way to avoid Long COVID is not to get infected by SARS-CoV-2. But if someone does get sick, “Rest is incredibly important to give your body and your immune system a chance to fight off the acute infection,” says Dr. Janna Friedly, a post-COVID rehabilitation specialist at the University of Washington who recovered from Long COVID herself. “People are sort of fighting through it and thinking it’ll go away in a few days and they’ll get better, and that doesn’t really work with COVID.”
Researchers are still learning a lot about Long COVID, so it’s impossible to say for sure whether it can truly prevent its development—or, conversely, whether premature activity causes complications. But anecdotally, Friedly says many of the Long COVID patients she sees are working women with families who are hit to get back to normal as soon as possible. It’s hard to give one-size-fits-all guidance about how much rest is enough, but Friedly recommends anyone recovering from COVID-19 stay away from high-intensity exercise for at least a couple weeks and avoid pushing through fatigue.
For people who have already developed Long COVID, rest can also be useful for managing symptoms including fatigue and post-exertional malaise (PEM), or crashes following physical, mental, or emotional exertion. The US Centers for Disease Control and Prevention recommends “pacing,” an activity-management strategy that involves rationing out activity and interspersing it with rest to avoid overexertion and worsening symptoms.
In an international study published last year, researchers asked more than 3,700 long-haulers about their symptoms. Almost half said they found pacing at least somewhat helpful for symptom management. Meanwhile, when other researchers surveyed about 500 long-haulers for a study published in April, the overwhelming majority said physical activity worsened their symptoms, had no effect, or brought on mixed results. That may be because long-haulers have impairments in their mitochondria, which generate energy cells can use, recent research suggests.
Before Long COVID existed, researchers and patients encouraged rest and pacing for the management of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). The condition’s hallmark symptoms include PEM and serious, long-lasting fatigue—diagnostic criteria that many people with Long COVID now meet. A study of more than 200 people with Long COVID published in January found that 71% had chronic fatigue and almost 60% experienced PEM.
For years, clinicians have tried to treat ME/CFS patients by gradually increasing their physical activity levels. But that practice has since been shown to be not only ineffective, but often harmful, because people with ME/CFS “have a unique and pathogenic response to overexertion” due to cellular dysfunction, explains Jaime Seltzer, director of scientific and medical outreach at the dysfunction advocacy group MEAction. Most people with ME/CFS prefer pacing over exercise-based therapy, one 2019 study found.
To pace effectively, people must learn to pick up on cues that they’re overdoing it and unlearn ingrained ideas about productivity, Seltzer says. “If you’re doing laundry, for example, there’s nothing that says you have to fold every single item in one sitting,” she. Breaking up tasks may feel odd, but it can be crucial for preserving energy.
People with new Long COVID symptoms should keep a log of their diet, activity, sleep, and symptoms for a couple weeks to learn their triggers, Friedly says. For those who can afford one, a fitness tracker or other wearable can also be helpful for assessing how much exertion is too much, Seltzer says. Once someone has an idea of behaviors that improve or worsen symptoms, they can use that information to plan their days and divide activities into manageable chunks.
For many people who test positive for COVID-19, however, even taking a few days off from work to isolate is a financial and logistical challenge. Many people have no choice but to return to physically taxing work or responsibilities like child care as soon as possible. “Rest is absolutely advice that’s weighted socioeconomically and politically,” Seltzer says.
People with Long COVID or ME/CFS may be able to secure workplace accommodations, such as working from home, taking on a role that can be done sitting instead of standing, or applying for disability if necessary. Seltzer also suggests leaning on friends, faith groups, or mutual aid networks for help with some tasks. Beyond that, Friedly recommends looking for creative ways to use less energy throughout the day. When she was living with Long COVID symptoms, she bought many pairs of identical socks so she’d never have to waste time and effort searching for a match.
Things like that “may seem small,” she says, “but if you add those up throughout the day, they make a big difference in terms of how much energy you’re expending.”
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