In one of the Taekwondo forums I belong to, the idea of new "safety protocols" are being discussed. One such protocol would be to require athletes to compete while wearing face masks. Anyone with even a little bit of common sense should see what a horrible idea this is. Physical activity triggers rapid breathing and heart rate, requiring more oxygen. But instead, we're going to put a mask on to limit the supply of fresh air and recirculate carbon dioxide back into the system. Do you know what happens then? You die.
If you want to wear a mask while running errands around town, go for it. I won't tell you how to live your life. But by no means should you wear one while exercising. Unlike the coronavirus, the risk of dying from that is actually high.