The best protection will come from N95 and KN95 masks, but they can be tricky to wear comfortably while exercising. There are currently two sports masks that are ideal for Covid Protection.
Very happy with this mask so far. It can be adjusted and works great for not breathing in debree. I am a dog groomer, so groomers lung is a scarry thing for me. But so far, i can tell a difference in how i feel at the end of the day. The mask is very breathable and lightweight.