Exercise After COVID-19 Can Be Dangerous — Even If You Feel Better

Exercise is a hugely important part of my routine and my life. For the better part of two decades, I’ve rarely taken off more than a few days from my regular routine. Usually, after a cold or a bug sidelines me, I’m right back in my routine.

And normally that’s fine. In a non-COVID-19 world, doctors say if you’re a regular exerciser, there’s no problem getting right back to your usual level of activity after illness. But we’re not in a non-COVID-19 world anymore, and as a result, the normal rules of returning to exercise may not apply. In a COVID-19 world, exercise can be dangerous, and in some cases, even fatal.

In an article for the New York Times, Dr. Jordan Metzl, a sports medicine physician at Hospital for Special Surgery in New York, wrote that when it comes to COVID-19, his usual advice–to return to exercise if it usually makes you feel better–doesn’t necessarily apply. He noted the cardiac and blood clotting complications he and his colleagues were seeing in “previously healthy and fit patients who had experienced only mild illness and never required hospitalization for COVID-19.”

Cardiac Complications

The link between a COVID-19 infection and cardiac complications continues to emerge. Studies have found that even in those who experienced mild or insignificant symptoms, heart damage is possible, especially if those people exercise while infected.

One of the concerns for patients is myocarditis—an inflammation of the heart muscle, which weakens the heart and makes it difficult to pump blood. Demanding activity while the heart is weakened can cause serious complications including dizziness, shortness of breath, cardiac arrest, and sudden death.

A study in JAMA Cardiology that looked at 100 folks—mostly health with no pre-existing conditions—who had recovered from COVID found signs of myocarditis in 78 percent. Twelve of those patients had mild or asymptomatic cases, according to Eric Topol, a cardiologist in contact with the study’s authors. Another smaller study that looked at college athletes found that 15 percent showed signs of heart inflammation.

Myocarditis was one of the main concerns the Big Ten and Pac-12 college conferences cited when determining whether to postpone the 2020 fall sports season.

Blood Clots

The link between COVID-19 and blood clots is still very much a mystery, though researchers are getting closer to understanding how and why COVID leads to blood clots. And yet, even without knowing exactly why COVID leads to blood clots, we do know the risk is there—particularly for those with severe infection, but also possibly for others.

In his article, Dr. Metzl wrote about a cyclist in her 40s who developed leg pain after experiencing COVID-19 symptoms. An ultrasound of her leg revealed “near complete cessation of blood flow because of arterial and venous blood clots in both legs.” The condition was found and treated before the clots spread to her lungs, which could have been fatal.

In Indiana, a twenty-year old college student died from a blood clot in her lungs after experiencing COVID-19 symptoms.

How To Safely Return To Exercise Post COVID-19

Dr. Metzl and his colleagues recently published “an evidence-based set of guidelines” to help patients return to activity after moderate to mild COVID-19 infections.

His recommendations include:

1. Do not exercise if you are still sick. If you are experiencing active symptoms “including a fever, cough, chest pain, shortness of breath at rest, or palpitations” you should avoid exercise. With respect to myocarditis, rest during illness and recovery may allow the inflammation to recede.
2. Slowly return to exercise. Even those who experienced mild symptoms, without chest pain or breathing issues, should wait at least a week with no symptoms before returning to exercise, and then then, should start at half their normal intensity. Saurabh Rajpal, a cardiologist and assistant professor of internal medicine at OSU, echoes that advice and suggests taking a few weeks off from exercise after testing positive for COVID-19 before gradually returning to your normal level of activity. It’s even recommended that asymptomatic athletes who test positive for COVID-19 refrain from exercise for at least two weeks.
3. Stop exercise if symptoms return, particularly chest pain, heart palpitations or breathing troubles. If those occur, be sure to see a doctor.
4. Some patients should see a cardiologist before exercising. Metzl suggests seeing a cardiologist if “you experienced chest pain, shortness of breath or fatigue during your illness.”
5. Get tested. It’s important to get a COVID-19 test if you have cold or flu symptoms so that you can make appropriate and safe choices for returning to exercise, if and when you are ready.

His most important suggestion: Listen to your body. Because it’s possible to have COVID without symptoms, it’s important to listen to your body. Rest when you need rest and see a doctor if you’re noticing changes to your normal activity levels.

While everyone should practice caution before returning to activity, those who suffered severe infection and/or required hospitalization should consult a doctor before returning to activity.

COVID-19 can affect nearly every system in the body and can cause folks to experience life-altering symptoms weeks and months after their initial infection—even among those who experienced mild symptoms. It is an illness that is unlike anything we’ve seen before, and as a result, we cannot act like we’ve always acted.

Vaccines are coming. The light at the end of this long, dark pandemic tunnel is visible. In the meantime, wear a mask, social distance, wash your hands—and listen to your body.