Like a fire for your feet.
We might talk about "setting your shoes on fire" because you ride so fast, but that's just an overused metaphor, not a suggestion as to how you might stay warm during cold-weather base miles. A far better idea is to wear the Mavic Ksyrium Pro Thermo+ Shoe Covers, which keep you warm, dry, and riding hard without the risk of burning yourself.
They feature a waterproof, breathable membrane, like you'd find in a technical rain jacket, and a water-repellent DWR coating to keep rain, sleet, and snow from freezing your feet. A layer of thin, light Primaloft Sport insulation traps plenty of heat, and Hypalon reinforcements at the toe and heel offer increased weather protection and durability. Mavic includes a zipper at the side of the foot for ventilation and easy access to your shoes' Boa dials or ratcheting buckles. The booties are finished with a wide opening for cleats and reflective details to help keep you visible when you're riding in inclement weather.