Runners, be wary. Before all of this I was running 20-25 miles a week, swimming once a week and doing 1 bike workout (usually at the gym). I had been planning a spring marathon and a half-ironman this summer (Both were canceled). Now, I can't run more than 1M at a time and not frequently.
I had most of the classic COVID-like symptoms, starting in late February, but the symptoms were mild and I couldn't get a test. As I started feeling better, I tried running but it caused a relapse of symptoms, especially shortness of breath, lung soreness and chest tightness, so I mostly walk at least 1M a day, which has been tolerable.
Because of these issues, I got in to see a doctor in early June. Tested negative for antibodies and my lungs and heart were normal, so my doctor thinks it's a post viral issue and encouraged easing back into exercise but also expect not be back to normal for at least a couple of more months. I've done a few 30 minute bike rides since and I did my first 1-mile run in a month a half last week. I did feel like I was improving until this past weekend where my HR spiked a little too high and that seemed to trigger a more intense relapse where I now need to take several days off to recover.
While maybe it wasn't COVID, I'm also part of a COVID group where there are scores of people, including runners and healthy active people, with similar stories about long haul symptoms/but negative tests and people who test positive initially but then don't test positive for antibodies. I've also read antibodies can ebb after a couple months (I was tested 3 months later). Some of theories why all this might be is apparently some people's immune systems clear the virus with T-Cells/IgA antibodies without producing much if at all of the IgG antibody (the one typically measured).
I do think my running fitness helped me through all this (I have run most of my adult life/now in my 40s, including several marathons and triathlons). Still, I've gained about 10 pounds since not exercising like I normally would and my lungs definitely aren't the same. I want to improve fitness as much as I can, because with no antibodies/affected lungs, I'm probably now at-risk.
Runners, be wary. Stay safe.