I live in Anchorage. When it gets below 10 I wear a thin balaclava that covers my mouth. I use it cross country skiing and sprinting. Easy to breathe through and no cold air/lung issues. Without it I end up with a cough. I sprint on the street I live on. It is snow covered and icy. Usually use Nike Frees but if really icy I use Ice Bug running shoes which have snow tire studs imbedded in the soles. Feels like you are zippered to the ground.