For Adam Harmon, Covid-19 began with a bad headache. Then came the fever and muscle pains. “I felt really achy for a day or two,” says the 31-year-old Park City, Utah–based endurance athlete. Harmon has been a triathlete, “semicompetitive” bike racer, and runner for years, but in the months before he caught Covid-19 in November 2020, he’d been mostly running and cycling to stay in shape and get outside. The virus knocked him out, and for about a month he experienced a cough and a diminished ability to smell and taste. He also noticed symptoms of “Covid toes,” a problem linked to impaired circulation that made his fingers and toes feel cold, “almost like I had frostbite,” Harmon says. He waited a month after his symptoms subsided before resuming exercise. But even then, he felt residual effects of Covid toes, which caused discomfort when he ran and was bad enough for him to cut short a ski outing because he couldn’t keep his toes and fingers warm.
Giving the body time to repair
As researchers are learning more about the novel coronavirus, important questions about resuming exercise after Covid-19 — and how to do it safely — remain unanswered. “This is a new disease,” says Philip Skiba, MD, a sports physician and physiologist at Advocate Aurora Health System in Illinois. “As physicians, we have had to sort of make it up as we go along.”
“What worries us is that this is indicative of permanent damage to the lungs, like there’s actually been scarring.”
Despite missing data, experts agree that before returning to normal exercise after Covid-19, it’s crucial that the body has enough time to repair. Research has shown that SARS-CoV-2 wreaks havoc on many organs, but particularly on the heart and lungs — organs that are crucial during exercise. Returning to high-intensity activities too soon could potentially worsen tissue damage in these organs, doctors fear.