Here are some tips to keep you warm on your runs so you can still get in those long runs and not have to run on that dreaded treadmill all winter long.
Layers are a lot more important for the upper body than the lower body. This is because your legs generate much more heat than your core does while running. Most runners can get by with tights on cold runs but if it is <10 degrees then an extra pair of insulation is a good idea.
For the upper body wearing more than 1 layer is ideal. The first layer should be a sweat wicking layer that helps move sweat away from the body in an effort to keep you warm. The second layer should be a fleece material to help keep you warm when it is really cold. The outer layer should be a protective layer to protect and keep you dry from wind, sleet, snow, and rain.
Dress 20 degrees warmer.
Dressing for a warmer temperature than it actually is will allow your body temperature to increase without making you oversweat.
You lose 40% of your body heat through your head.
Wool or fleece hats or headbands are great for keeping body heat in. Another good thing to wear is a bandana or a scarf to keep your neck warm. You can also pull the bandana up over your mouth to keep the air you breathe warm.
You can lose up to 30% of your body heat through your extremities.
Wear gloves to protect your hands. Never wear cotton socks on runs. Cotton socks do not help to wick away moisture, leading to blisters. They also don't keep your feet very warm. Wear socks that are specific for running or wool socks when it is really cold out. If you are planning on running through the snow rather than plowed trails then wearing a trail shoe is a better option as it won't soak up as much water.
Staying hydrated is very important. Running while dehydrated is never a good option especially in the colder months. When the weather gets cooler most people don't think about replacing lost fluids as much as when it is hot and they sweat a lot more.
In the winter everything looks dull and dreary. Avoid wearing colors such as grey, black, or navy. Wear bright colors and reflectors so you can be seen by others and avoid accidents.
Dress for the Environment
If you are running in New York you are going to dress differently than you would if you were running in Indiana. This website has great tips on what to wear depending on what part of the country you live in. This is also great to look at if you plan to be traveling this winter and still want to run while you are away from home!
Sources: http://www.runnersworld.com/cold-weather-running/comfort-zones, http://www.active.com/running/Articles/Running_in_cold_weather, http://running.about.com/od/coldweatherrunning/a/wintergear.htm, http://www.active.com/running/Articles/Winter-Running-Tips.htm