It can affect more than just your lungs.
As with many things with the new coronavirus, however, there are still a lot of unknowns, so there are no clear-cut answers. We just don’t know who is likely to develop the kinds of COVID-19 complications that can make exercise difficult (or in some cases dangerous).
But it does seem that the more severe your COVID-19 infection is, the more likely you are to develop longer-term complications that can affect physical activity afterward, infectious disease expert Amesh Adalja, M.D., a senior scholar at the Johns Hopkins University Center, tells SELF.
And these COVID-19 complications aren’t necessarily limited to your lungs: While experts believe the virus can only infect cells that have the special receptors it needs to bind to them—which are primarily located in your respiratory tract—it also has the ability to cause multi-system organ distress due to your immune system’s reaction to it, Adalja says. That’s the cytokine storm, or inflammatory cascade, we hear of associated with COVID-19.
So while the new coronavirus primarily targets your lungs, other organs, like your heart, can be affected too. And that’s especially important for any exerciser, since the healthy functioning of those organs obviously plays a super-important role in allowing you to work out safely.
As the number of people who have recovered from COVID-19 grows, so does the question of what getting back to physical activity after coronavirus recovery will look like for them. Here’s what we know about how COVID-19 can affect your body afterward—and what you need to know before getting back into the exercise groove.
How coronavirus can affect your lungs
Remember those special receptors that allow the virus entry? Well, one of the unique features of the new coronavirus is that it can bind to receptors in both your upper respiratory tract—giving you common-cold symptoms like a runny nose and cough—and in your lower respiratory tract, Hallie Prescott, M.D., an assistant professor in the division of pulmonary and critical-care medicine at the University of Michigan Health System, tells SELF.
The involvement of the lower respiratory tract triggers inflammation in your lungs as your body tries to fight off the virus, potentially setting the stage for pneumonia.
While it’s possible that this inflammation can persist and progress to fibrosis, or scarring, in the lungs, we don’t have enough long-term data to suggest how likely that may or may not be with COVID-19, Lina Miyakawa, M.D., a critical-care pulmonologist and assistant professor at Mount Sinai in New York, tells SELF. So the next best way to gauge the possibility of long-term damage is to look at data for related illnesses, like SARS (another coronavirus). A study of 383 hospitalized SARS patients found just over 20% experienced some kind of lung fibrosis, though this scarring tended to improve over the course of 12 months. Other research on survivors, though, showed that some still noticed an impairment in a measure of lung function after one year.
Again, the sicker you are, the more likely you are to experience lasting effects, says Adalja. That makes people who experienced respiratory failure or those who needed mechanical ventilation at greater risk of long-term lung damage. “It might take months [to recover from the damage], and some of that can be permanent in terms of exercise tolerance and physiologic reserve,” he says. It’s just not clear now what the long-term potential for scarring is, though, for people with milder cases.
Another possibility, even in not-so-sick cases of COVID-19, is adult-onset asthma. Other viruses are known to trigger the breathing condition in people who’ve never had it before, so it’s possible COVID-19 can do likewise, says Prescott. If that’s the case, you might start to experience chest tightness, wheezing, coughing, or shortness of breath, especially during physical exertion.
Most people who’ve had COVID-19, though, will likely get back to their normal lung function, Prescott says. It just might take a while to get there: It can take six weeks to feel you’re back to normal, she says (though of course it varies on an individual basis). Until then, symptoms such as cough, shortness of breath, and fatigue can persist, making your regular exercise routine feel harder than usual.
How coronavirus can affect your heart
Research on hospitalized COVID-19 patients shows that heart problems can occur with more serious cases: A study published in JAMA Cardiology of 416 hospitalized patients in Wuhan, China, found that nearly 20% experienced cardiac injury associated with the virus. With other viral illnesses, the rate is much lower, at just about 1%, according to separate research, also in JAMA Cardiology, on the return to exercise after COVID-19.
Cardiac injury is a broad term, but it refers to the release of biomarkers called troponins into the bloodstream, which serve as evidence that the heart has been weakened in some way by the virus, explains Jonathan Kim, M.D., chief of sports cardiology at Emory University and coauthor of the latter JAMA Cardiology paper. This may be due to the inflammation overload triggered by COVID-19, which can cause heart arrhythmias, blood clots (possibly leading to heart attack, stroke, or pulmonary embolism), or even a dangerous condition called myocarditis, or inflammation of the heart wall, he says.
Myocarditis—a leading cause of sudden death in athletes—is a particular concern to those who exercise. Continuing to exercise if you’re already sick with the virus (even if you’re not necessarily having symptoms) can make the existing myocarditis worse, says Kim, since it can increase virus replication in your body. This increased inflammation can potentially lead to the formation of permanent scarring on your heart, which can trigger arrhythmias.
This cardiac injury can cause exertional symptoms—extreme shortness of breath out of proportion to the activity you’re doing—racing or irregular heartbeat, chest tightness, lightheadedness, or passing out, he says.
But what does all this mean for people with more mild or moderate cases of COVID-19 who weren’t hospitalized? There’s currently no data to answer that, but the heart complications seen in sicker patients are enough to raise concern even for those not as ill, says Kim. And people with preexisting heart conditions or other medical conditions might be at even greater risk for these heart complications.
Experts also aren’t sure when in the course of COVID-19 illness heart issues might arise, but there is data to suggest you can feel relatively fine the first week, and then deteriorate with more serious issues the second week, he says. So it’s important to give yourself ample time to recover before starting to exercise again (more on that below).
When can you start exercising after coronavirus?
Because of the potential for serious complications with COVID-19—and the unknowns regarding who may be more likely to experience them—experts have recently published two separate guidelines on the return to exercising after coronavirus. And they align pretty closely in their recommendations to take a break and come back slowly.
In June respiratory experts from the U.K. recommended in The Lancet that due to a risk of deterioration around days seven to nine, athletes should hold off on resuming regular training for at least 10 days from symptom onset and seven days from symptom resolution.
Kim’s paper from May—a consensus document with the American College of Cardiology’s Sports and Exercise Council to advise athletes—recommends a two-week exercise break before a gradual activity resumption for athletes with COVID-19 who were asymptomatic. Those with mild or moderate COVID-19 should take a two-week break following the resolution of their symptoms, and also undergo troponin tests and imaging tests like cardiac ultrasounds. Athletes hospitalized with COVID-19 would require more careful testing, and if cardiac abnormalities were discovered, they should stop competitive training for three to six months (in line with the return-to-play rules governing myocarditis).
Those rules apply to competitive athletes and high-end recreational athletes—say, a regular marathoner or a triathlete. But what about the regular, general-population exerciser? In that case, Kim still recommends at least 7 to 10 days of no exercise from the time of testing positive for those who were asymptomatic, and about a week after symptom resolution for those who were mildly or moderately ill. Most people at this level probably don’t need to undergo testing such as blood work or cardiac ultrasounds before resuming exercise.
“If you had COVID, but it was mild and you recover, it’s probably reasonable to slowly engage back to your routine of exercise,” he says. Of course, if you have preexisting health conditions, or you experience cardiac symptoms like those mentioned above when you start exercising again, talk to your doctor before continuing. (It’s important also to remember that cases can show up asymptomatically, meaning you may not know you have it—and thus you may not know to be careful with exercising. So it’s vital to keep practicing prevention measures to avoid exposure.)
How should you ease back into exercising after coronavirus?
Ease is the operative word. Even if you have a mild or moderate case of COVID-19 and you don’t develop any serious complications, you might still not be able to get right back to your regular exercise routine right away.
Experts think some people may develop a post-viral syndrome after COVID-19 that can leave them feeling fatigued for a few weeks or longer even after other symptoms resolve, says Adalja. And that, of course, can make physical activity difficult. Plus, simple deconditioning—say, from a couple weeks of bed rest or couch rest while convalescing—can make even your normal routine feel harder, says Miyakawa. (That’s why it’s important to try to get out of bed when you’re sick, even if it’s just sitting up in a chair or walking around the room, and taking purposeful deep breaths to help keep your lungs in shape.)
“A lot of people are going to feel like crap when they get back to exercise, and that’s very very common,” Prescott says. “You’re going to have to do a lot less at first and gradually build up to do what you were doing beforehand.”
First, if you’re experiencing any of the symptoms noted above when you begin exercising—like chest pain, irregular or racing heartbeat, or severe shortness of breath out of proportion to what you’re doing—stop exercising immediately and check in with your doctor. But if you’re just feeling a little more short of breath than usual, get tired more quickly, or cough a little, you should focus on gradually increasing the duration of your physical activity as you get stronger, says Prescott. (If you’re concerned about these symptoms, though, definitely connect with your doctor to make sure they are part of a normal recovery.)
One helpful way to do that is to track your sessions and add to them—say, if you walked for five minutes one day before feeling exhausted, maybe the next, you can make it to six minutes, and so on, she says. (You also definitely want to start with low-intensity activity, like walking, to ease your body back into it before you start thinking of more intense forms, like running.)
Another possibility is to break up your workout as you start to feel better. If you were doing 30-minute cardio sessions before, maybe you split them up into three 10-minute sessions throughout the day to help your body adjust, Prescott says.
It can take weeks from the time your symptoms resolve for you to feel back to normal. But if you can’t seem to make progress building back your endurance or stamina even with the structured increases of activity, you may want to check in with your doctor about the possibility of undergoing lung function tests or other imaging, Prescott says.
This article was originally published on SELF