This question gets asked a lot year after year during the winter months.
I have only a very mild cold and no COVID19 symptoms. I have no races in inter thank goodness. My cold is only a snuffly nose and a small cough.
But if you’re sick from the throat down you may want to spend the day at home. Also if you have a fever you shouldn’t exercise. You should just rest and hydrate.
Mild to moderate physical exercise is ok so long as its not a really long run out in the cold. One to two hours is fine.
Exercise and the Immune system
Exercise helps to boost the immune system so you may only get a very mild case of COVID19 or just a cold. But even still you might want to get tested for this. If you’re negative and its just a cold it would be alright to exercise.
The immune system is the body’s defense to fight off viruses. The more immune your system is the better you will be at not catching COVID.
If you exercise a lot you would have fewer colds and sickness. People that don’t exercise much are more at risk of COVID19. Thus this why we are fighting for gyms to be reopened as soon as possible. And for them to fall under the exercise category in the Stay at Home orders
In short listen to your body. If you’re ok and feeling good, go right ahead.