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When Dr. Jordan Metzl and his colleagues at the HSS Sports Medicine Institute published their guidelines for returning to activity after COVID-19 in August 2020, he never imagined the response he’d get from patients.
“I’ve been surprised at how many people have reached out to me,” said Dr. Metzl. At the time, long-COVID—patients who were still having mild to moderate symptoms three to five months later—was an emerging and unstudied phenomenon. “Maybe they just didn’t know where to go, people weren’t talking about it. There’s more people out there with these issues than I even realized.”
Now, two years into the pandemic, there are specific COVID rehabilitation programs paying more attention to the long-lasting effects of the illness.
The HSS team was one of the first to create frameworks for recreational athletes who had mild to moderate coronavirus to understand how to best return to activity safely. Similarly, the American College of Cardiology Sports and Exercise released their return to play guidelines in May 2020, directed at competitive athletes and highly active recreational athletes.
Since 2020, more medical institutions have taken a stance on the best practices to return to running after being sick with COVID-19. Though the answers are still not crystal clear, doctors understand better now what recovery from the illness is like.
What You Need to Know About Running After COVID-19
We spoke with pulmonologists, cardiologists, and sports medicine physicians to find out what runners need to know about running after having COVID-19.
If your illness was asymptomatic or mild:
“It’s important to recognize up front that it will take some time for your body to recover,” says Dr. Mark Wurfel, a pulmonologist at the University of Washington Chest Clinic. A message of patience rang loud and clear among all the medical professionals we spoke to.
And yes, that’s still the case if your illness was only mild.
A mild case is defined as common cold–like symptoms, GI distress, loss of taste or smell, and fever lasting less than two days.
Even with mild symptoms, you might not be back to 100 percent when you pick up your training again.
“We know that for people that have one day of true bedrest, it takes about three days to recover that endurance and strength back,” says Andrea Aagesen, DO, assistant professor of physical medicine and rehabilitation at University of Michigan Health. Knowing that, you can set more realistic expectations for your recovery.
Runners should take an inventory of how active they were at home during their isolation. Were you bed- or couch-ridden the entire time or were you up and about doing isolated activities? That will make a difference on where you start to come back to your fitness.
The recent update to the ACC recommendations now say that athletes who were asymptomatic can return to training after three days. Initially, they recommended 10 days abstaining from exercise. Keep in mind that the CDC still recommends 5 days of isolation after testing positive.
Dr. Metzl recommends that runners who had mild symptoms follow the 50/30/20/10 rule. In your first week back, your training load should be reduced by 50 percent of normal capacity. If that is comfortable and you’re not experiencing new symptoms, the next week’s training load should be reduced by only 30 percent, followed by 20 percent, and 10 percent in the fourth week.
“If you have a body system that’s been infected, it’s important to gradually tax that system to see where you are,” he says.
Gauge how you feel on the run, but also take the following day as a sign. If you feel totally wiped out the day after your run, you probably pushed it too hard. “Start low and go slowly to make sure you’re not experiencing that kind of big rebound fatigue,” says Dr. Chris McMullen, a physician at the University of Washington Sports Medicine Center.
If you’re feeling very weak and de-conditioned, Dr. Aagesen recommends cross-training a bit before you dive right back into running. Aqua jogging or indoor cycling are ways you can get in a cardio exercise without putting too much pressure on weakened muscles.
When you are back to running, if you don’t feel as steady on your feet, “go see a physical therapist or a sports medicine doctor to help figure out what has happened in the meantime,” she says.
One major question that runners are asking post-COVID is how long will it take to get back their fitness and feel normal again. The answer is frustratingly vague: It depends. Your time back to fitness will depend on how long you were out of training, the severity of your illness, and what lingering symptoms you have.
“If you are doing things right, you should see that the relationship between your heart rate and perceived exertion with your favorite runs will be returning to your pre-COVID levels in 3 to 4 weeks and will be the best marker of your cardiovascular and muscular recovery,” says Dr. Wurfel, adding that elite and younger athletes might recover even faster.
If your illness was moderate or severe:
The American Academy of Physical Medicine and Rehabilitation estimates that from 3 to 10 million Americans are living with long-COVID.
If your illness was moderate (fever lasting longer than two days, chills, flu-like symptoms, chest pain, shortness of breath, or palpitations) or severe, your return to running will be more complicated.
Once you get back to running, you can follow the same recommendations as above: listening to your body and going slow. But before you get there, you will most likely need to consult with a physician—especially if you experienced any cardiac symptoms.
According to the CDC, “many organs besides the lungs are affected by COVID-19 and there are many ways the infection can affect someone’s health.” In particular, concern surrounds how the virus interacts and causes damage to the heart. The inflammation and damage they are worried about is called myocarditis.
“Our primary concern, I would say, is still myocarditis,” says Dr. Aagesen. “That is what drives any kind of restrictions or limitations at this point.” Pulmonary embolism is also a concern.
And even though it remains a concern, emerging studies are finding that adverse cardiac events in athletes returning to their sport are relatively rare. Still, it’s always better to err on the side of caution. That caution is what has driven the return-to-sport guidelines from the beginning.
To avoid putting stress on the heart before it’s ready, runners shouldn’t plan to pick up where they left off in their training. Dr. Jonathan Kim, a sports cardiologist and co-author of the ACC return to play guidelines, also recommends runners pay attention if clear cardiac symptoms arise while they’re running, such as new chest tightness, excessive shortness of breath, feeling winded during an exercise that is normally easy, feeling lightheaded, or passing out.
In some cases, and under supervision, moderate exercise is prescribed to help patients reduce inflammation that seems to linger. “It’s got to be a really tight balance,” says Dr. McMullen, “because the other thing that people with long-COVID often experience is post-exertional malaise—extreme fatigue that can occur after exercise.”
Runners really have to slow down in these instances to get in their workout without causing a flare up in symptoms. Dr. McMullen typically prescribes his patients 10 minutes of light aerobic exercise a few times a week, increasing from there.
Lessons Beyond Coronavirus
Though COVID is in a category of its own, some of this advice is helpful for other common illnesses, such as colds and flu.
“Even before COVID I was always under the advice of, when you’re under the weather, that’s the time when you shouldn’t be going out and pushing yourself to the limits and very hard,” says Dr. Kim.
Dr. Metzl points out that it can be tough convincing runners, who are used to pushing through illness, bad weather, and stress to take a break. “We’re just programmed to run through everything,” he says. “Which honestly, in life in general, is probably a great attribute. We get stuff done. We don’t let stuff stand in our way.”
He emphasizes that now is not the time to just do what runners do. “As a sports doctor who’s seen patients that have all different issues as well as some of these post-COVID issues, I think this is a time where you need to really temper that runner mindset and put it in context with the fact that that’s not necessarily the best thing for runners right now. You want to be mindful, you want to be careful. You want to be more careful than you’ve been before.”
But if you genuinely feel good and are no longer infectious, there should be nothing that stops you from getting out and enjoying a run.
Editor’s note: This article has been updated with new information. We will continue to update this story as we receive new or expanded advice from experts. Please visit the CDC or World Health Organization websites for more information.