When Peter Gard began working out again after a mild case of COVID-19 last August, he noticed some occasional mild tightness in his chest.

“I just thought I wasn’t in as good of a shape as I used to be,” said Gard, a 20-year-old basketball player at Widener University.

But in December, after a routine physical exam for NCAA athletes, Gard found out he had myocarditis — an inflammation of the heart muscle that can reduce its ability to pump blood. His doctors believe it was related to COVID-19, Gard said, and asked him to stop all exercise that would elevate his heart rate.

After the diagnosis, Gard said, “I did a good amount of walking. Since then, my activity level has progressed a little bit. As long as I can talk through the workout, that’s OK.”

Medical experts have become increasingly concerned about the link between COVID-19 and lingering cardiovascular issues such as myocarditis. A study published in JAMA Cardiology in July found that 78 patients out of 100 who had contracted COVID-19 experienced cardiac irregularities, despite not having any preexisting heart conditions.

Such cardiac issues can cause someone to get tired faster due to shortness of breath, which can affect those who have resumed exercising after having COVID-19. Physicians at the Hospital for Special Surgery Sports Medicine Institute in New York City even published a guide in August on how COVID-19 patients can begin exercising safely again, including such tips as starting with low-intensity exercises and paying attention to how much they eat and drink.

While physicians would like to get people back to their “desired levels of activity,” there is still a lot of uncertainty about the lingering effects of COVID-19, said Marc Harwood, chief of non-operative sports medicine at Rothman Orthopaedic Institute.

“Ordinarily in medicine, we like to identify the source of the problem, treat the problem, and it goes away,” Harwood said. “But we don’t understand why some people who have had COVID develop these symptoms.”

Some of his colleagues believe the lingering symptoms are caused by a disruption in the connection between the lungs and the cells in the organs, he said, similar to the kind of nerve disruptions people who have lost their sense of taste and smell have experienced. During this time, it’s important to be sensitive to what the body can handle.

When patients experience shortness of breath or other difficulties when returning to exercise, Harwood recommends starting with light, non-weight-bearing aerobic activities such as biking or using an elliptical trainer. Patients often progress at different rates, he said, depending on how serious their illness was.

“Much like after the polio epidemic in the 1950s, we didn’t really know post-polio syndrome was a permanent issue,” Harwood said. “I worry that long haulers might be in it for the really long haul. We don’t have enough data with regards to how those folks are doing.”

Personal trainers have also had to adjust workout routines for clients who have had COVID-19. Victoria Williamson and her husband, Stephen, co-owners of BodyBlast, said some of their clients “need more recovery time between sets to catch their breath.”

“They’re more tired than usual, and we’ve had to slow down their personal training sessions,” Williamson said.

But the couple said these clients often recover their original levels of activity quickly. They encourage clients to eat more foods that can help support immunity, such as fruits and vegetables, and pay attention to their physical responses during workouts. Williamson said they also recommend that recovered patients wear an Apple watch, which will keep track of a heart rate and tell whether someone is getting enough oxygen.

“We recommend scaling it back a little bit, like cutting distance off of runs or going slower,” Williamson said. “Doing movements that aren’t as respiratory labored is also good. … We have our clients do movements that work similar muscle groups but don’t get their heart rate up as much. You can break burpees up into push-ups and squats, two basic components of a burpee, so they aren’t as demanding.”

At Platoon Fitness in Center City, owner har said he has seen only a handful of clients with limited cardiovascular capacity over the last year due to COVID-19.

“We’re not seeing a huge difference,” he said. “If I had a trainer randomly train one person who didn’t have COVID, and another trainer train a person who did have COVID, it would be very hard for us to tell which one had COVID in most cases.”

But even if someone feels good after recovering from COVID-19, Harwood recommends that athletes with a high level of activity get their heart checked to make sure there aren’t any issues before resuming exercise.

“We generally recommend that when people get diagnosed with coronavirus, they should not exercise within the first 10 days, even if they feel good,” he said. “That’s not necessarily based on hard data, but most sports medicine physicians are recommending that from the onset of symptoms to exercise, it should be no sooner than two weeks. And then you take it up from there, depending on how you feel.”

Gard, the Widener basketball player, is hopeful he’ll get the green light at an upcoming follow-up appointment to resume his regular level of activity after three months of rest.

“I’m being careful until everything looks good,” he said.

Tips for returning to exercise after COVID-19

  • COVID-19 patients who have experienced cardiac complications such as arrhythmia or myocarditis should rest for three to six months, with regular testing, before returning to regular levels of exercise.

  • Patients with respiratory symptoms from COVID-19 should carefully monitor how they’re feeling as they ease back into exercising, especially those who have a preexisting lung condition.

  • Those who have continued muscle pain should avoid intense exercise until symptoms are gone, then begin a gradual progression to normal levels of activity to avoid risk of injury.

  • Patients who suffered from gastrointestinal symptoms such as nausea and diarrhea should pay close attention to hydration and calorie intake as they return to exercising after recovery.

  • The National Strength and Conditioning Association and Collegiate Strength and Conditioning Coaches Association recommend following a 50/30/20/10 rule for athletes who have recovered from COVID-19. This means the first week, they should reduce their exercise load by 50%, followed by a 30% reduction the next week if comfortable at the end of the week, and so on until returning to previous levels of activity.