The cold is usually not as hazardous for the runner as is heat. With exercise metabolism, the body is able to maintain a constant core temperature in air temperatures as low as -30F. This is regulated by internal mechanisms and not necessarily by the heat produced from exercise. Shivering can be seen during exercise when the core temperature is low. Under this stress, oxygen consumption is higher than when doing the same amount of exercise in warm weather.

Common sense tells you to be comfortable while running; this is also true in cold weather. Both body fat and clothing act as heat conserving mechanisms. High body fat is not conducive to good performance and is not common in most runners, so most must learn to dress warmly. It is often difficult to determine how many clothes to wear in winter conditions. The heat generated by your body can be seven or eight times as great when running as it is at rest leading some runners to overdress at the start of their run.

On the other hand, if you are dressed to be “just right” when you are running hard and you must slow down or walk due to fatigue or injury, you risk the threat of hypothermia. You should attempt to stay as dry as possible. If clothing becomes wet either through sweating or external sources (rain, snow), it can conduct heat away from the body. Regulate your clothing so it doesn’t become sweat soaked, use materials such as CoolMax, Thermax or Poly-Pro which wick moisture away from your skin as you sweat, and wear a rainproof shell which sheds moisture and does not soak it up when it is precipitating.
When deciding what to wear for your run, first check the temperature as well as the conditions outside. Running with bare legs in cold weather is not advised. The red color of the skin shows that a great deal of the blood is detoured to the skin trying to keep the body warm and is not going to the exercising muscles where it is needed most. Cold muscles feel tight and are more susceptible to injury, especially pulls and strains.

May I suggest running tights or other leg coverings when the temperature is below 40 degrees. Many options in materials for tights are available, from water resistant to extra warm fuzzy PolyPro, which can be worn as the conditions change. Fabrics that are waterproof, but can still breathe are best for external layers.

Gentleman, winter briefs are an excellent, and much advised option, other than wearing your running shorts under tights. Gortex works quite well if you don't sweat a great deal. CoolMax is excellent next to the skin as it wicks away moisture and allows a warm air layer to remain. A major part of heat loss is through the head, so wear a hat or ski headband to help keep warm. Gloves are important as well and range from cotton to Polypro to Gortex. If it’s wet, polypro keeps hands much warmer and the Gortex mittens on top on a rainy day are a sheer indulgence. You can remove gloves, hat or layers of clothing as you become warmer. Check your local running store for the latest in winter running fabrics.

Here are a few guidelines that will help you get through your winter runs:

Warm up prior to going outside
On very cold days, it’s a great idea to do some exercises or warm-ups prior to going outdoors. You may walk around the house, jog in place, do some jumping jacks or pushups, etc. The idea is to head out the door already warmed up (not sweating) so the first few minutes or miles are not spent trying to warm up in an already cold environment. Remember, the body’s defense mechanism when it’s cold is to pull blood from the extremities to your core to keep the body temperature regulated.

Dress in layers
You are better off to overdress than underdress. Very few people die from overheating in the winter but many from suffer from hypothermia. It’s always a good idea to dress in layers during the cold, wintry months. Start off with a base layer of a t-shirt and add a long sleeve shirt over the top of that. Depending on what the temperature is where you live, either wear a “shell” jacket on over that or a heavier running winter jacket. All layers should be made of breathable material to wick away the moisture from your skin. Having fabrics that pull the sweat away from your skin will keep you comfortable and warm during the cooler months. Winter “briefs” work much better than regular running shorts. Trust me on this. Cover up all your extremities (hands, ears, feet) with extra layering. When temperatures drop below 10 degrees F, do not expose any skin, if at all possible. Sunglasses also help with the sometimes-stinging cold wind, especially if you wear contacts.

Wear something reflective

Where to run
The ideal places to run are roads and paths that are well lit. Usually these areas also have a sidewalk on which to run on as well. If you are fortunate enough to have a lighted track, by all means use that facility. The track is generally cleaner than the roads and you are less likely to injure yourself.

Run facing traffic
It makes sense to run away from cars, such as on a bike path or the sidewalk. Always run facing traffic so as not get hit from behind. Sometimes the lights from oncoming cars can be blinding so you can either look away from the headlights (recommended) or close your eyes just as the car gets to you. This will offset the temporary blindness that sometimes occurs. As a car approaches, it’s a good idea to look at the road in front of you to look for things that may be in your way that you may not have otherwise known were there. The most dangerous crossing is in front of a car turning right (without using their turn signal) with the driver only checking out what’s coming from their left. Make direct eye contact and also look at their front tires to see which way they are turned. Never step in front of this car without recognition from the driver. My favorite trick to alert drivers (though not always appreciated) to make sure they need to look is to run behind the car and slap the trunk to make them aware I’m there. Then smile and say, “you need to look both ways.” Be careful of this though. I’ve gotten into shouting matches with the “cell phone glued to the head and not paying attention crowd” on numerous occasions. Just be careful with this maneuver.

Remember to drink
You might think that there is no reason to drink during your winter runs. Do not make that assumption. Taking in fluids during your runs, and long weekend runs, is as important as doing so during the summer. By not drinking enough during the winter, you run the chance of dehydration. Not to be crass but pay particular attention to the color of your urine. The clearer the better. If it’s a wheat, and especially gold color, you are becoming or are already dehydrated. Don’t rely on “feeling thirsty.” By that point, you’re probably already dehydrated. Dehydration leads to muscle fatigue, thickening of your blood (i.e. your body works harder to function correctly) and slows recovery. It’s generally dryer during the winter so remember to drink frequently throughout the day.

Take some time off
Cross-train, ride a mountain bike, downhill or cross-country ski, find a new hobby, learn a new language, spend quality time with family and friends, indoor cycle, swim, etc. The list is endless. The winter season is a great time for some time off. It should be part of your yearly plan. It’s as important in your training as much as running is.

Build your aerobic/endurance base
Contrary to the “take some time off” note, this is the perfect time of year to get a great aerobic/endurance base built up. There is no real reason for most people to do any type of “real” speed work (i.e., track workouts) working on your aerobic base will ultimately make your race better next season anyways.

Planning for the cold dark months of winter can keep your running on track. I hope I’ve given you a few ideas to keep getting you out the door this winter.