Do not worry about breaking records
First of all, you need not to worry about increasing mileage or pace during winter times because the cold and icy condition make it more prone for you to slip and injuring yourself. We would like to also advise you to do your warm up indoors. Try to avoid icy roads and go for the snow, which provide better traction and grib. Shorten your stride and run slower for the sake of keeping safe during very ice and wet days ahead.
Not surprisingly, you must wear proper winter clothing if you want to run during the winter. Wear thick dry socks and use slightly larger running shoes to accommodate the space needed for these socks. It is essential to keep your feet warm during winter runs to prevent frostbite and vessel problems. Also wear a warm hat during your runs. A great amount of body heat vapors through the head during cold condition and this will affect the circulation in your body. Your hands must be covered in wool gloves and you must also wear thick running suits. For shorts, you can wear those made of polypropylene or Lycra and combine it with wool running trousers.
You must be careful and avoid running into a wind-chill. This extreme cold can be bad and dangerous. Experienced runners like to run into the wind to start their run and then return to the starting line with the wind blowing at their backs. This will make your return run easier as your body has become warmer.