Running In the Cold

By Rick Morris

Running in the cold presents hazards that many runners are not properly prepared for. When most runners think about the environmental dangers of running, they are usually more concerned with the dehydration or heat exhaustion that comes with hot weather running. Running in the cold can also present a number of problems that you should be aware of and properly prepare for.

Unlike hot weather, running in the cold can sometimes sneak up on you. Most mountain and trail runners are well aware that weather conditions can change quickly. It is not uncommon to begin a mountain run in mild weather conditions and end up running in a blizzard. But, that can also happen during road runs. Several years ago I was running a half marathon road race in Colorado.  It was a pleasant October morning with mild temperatures and overcast skies – nearly perfect running conditions. I was born and raised in Colorado and knew that conditions could change quickly, but it was such a nice day I walked out the door wearing only shorts and a tank top.

Just as an after thought I went back to the house and grabbed a pair of warm running tights, a long sleeve shirt and an all weather jacket. I got to the race, warmed up and headed for the starting line. Nearly every other runner was dressed as I was – just shorts and a light shirt. Only minutes before the start an icy wind kicked up and it began to spit snow. I sprinted to my car and changed into my cold weather gear.

It is a good thing that I did. By the time I hit the finish line, I was running through three inches of snow and the temperature had dropped to the low 30’s. Even in my warmer gear I was shivering from the cold. I saw many runners who bravely kept running in their light weight clothing, but they kept the emergency medical personnel busy treating cases of hypothermia.

The lesson I learned is that you cannot ignore the dangers of running in the cold. The most common danger of running in cold weather is hypothermia. Hypothermia is not only a dangerous medical condition, but it will also affect your running performance. We all know that our normal body temperature is 98.6 degrees Fahrenheit. When your core body temperature drops your body compensates by diverting blood away from your arms and legs to your body core in an attempt to keep your core temperature at normal levels. The result – decreased running performance.

Hypothermia occurs when your core body temperature drops below normal levels. While hypothermia is more common in very cold weather, it can be a problem in even mild conditions if you become chilled due to rain, water or sweat. There are three stages of hypothermia. Each stage is more dangerous and severe. It is important to recognize the early symptoms to avoid serious medical problems.

  • Mild – Core Body Temperature of 95 to 97 degrees F. Symptoms include cold sensation, goose bumps, mild shivering and numb hands.
  • Moderate – Core Body Temperature of 90 to 95 degrees F. Symptoms are violent shivering, stumbling pace and difficulty speaking.
  • Severe – 75 to 90 degrees F. Common symptoms are poor muscle coordination and a lack of shivering. Confusion in the early stages can be followed by unconsciousness and eventually death.

Another potential problem of running in the cold is frostbite. I think that most of us that live in areas of cold weather have had a run in with Jack Frost. There are four stages of frostbite. The first two stages are known as early cold response and frostnip. Early cold response is common in cold weather and is recognized by a cold, painful feeling and a red color to your skin. This is an early warning sign that you should come in out of the cold. Early cold response is followed by frostnip. At this stage your skin may become numb or you may have some sensation. Your skin takes on a white color.

The first two stages are reversible, but at the frostnip stage you are approaching the more dangerous superficial and deep frostbite stages. Both superficial and deep frostbite are serious conditions and require medical attention. In superficial frostbite your skin is numb, white and soft. If exposure to the cold continues you could suffer from deep frostbite in which your skin becomes firm.

There is an effect that can make the cold injury even more common to runners called the wind chill effect. When you are running you are creating your own wind chill effect. If you are running at 8 MPH you are in effect creating an 8 MPH wind. That wind passing over your body exaggerates the effects of the cold and makes you even more susceptible to cold injury.

Runners have three choices when it comes to running in the cold. Run outside in the cold, run inside on a treadmill or don’t run at all. The last option is not acceptable. After all, we have to run sometime. Running inside on a treadmill is a good option, but some runners either don’t have access to a treadmill or hate running on them. That leaves only option 1 for most runners. You can run safely in cold weather, but you must pay attention to and prepare for the dangers of cold

Dressing For Cold Weather

Dressing for running in the cold can be a challenge. If you dress so that you are warm at the start of your run you will probably be over heated at the end. When running in cold weather always remember one word – layers. The layers of clothing will keep you warm by trapping heat against your body. As you generate heat during your run you can remove layers to avoid overheating.

I recommend wearing either two or three layers depending upon the weather conditions. Each layer has its own purpose.

  • Layer 1 – The purpose of the first layer is to wick moisture away from your skin. A long sleeve cotton shirt is a common choice for the first layer. This type of shirt will wick away the moisture, but creates another problem by holding on to that moisture. The cotton soaks it up like a sponge. A better choice would be an acrylic fabric, polypropylene of one of the new high tech fabrics that are designed to keep the moisture away from your skin.
  • Layer 2 – The second or middle layer should insulate your body and keep you warm. This layer should be made from an insulating material such as fleece or heavy cotton. It should also be able to absorb a small amount of moisture so that it can assist your first layer in keeping your skin dry and warm.
  • Layer 3 – Your third or outside layer is there to break the wind and keep rain or snow away from your insulating and wicking layers. This outside layer should be made from a waterproof material such as Gortex or nylon.

During moderately cold and dry weather you may need only two layers. If it is extremely cold, raining, snowing or windy you should wear the third outside layer. One rule of thumb is that you should be a bit cold when you start running. As you run you will begin to generate a lot of body heat which will warm you up. If you are comfortable at the start you will overheat rapidly.

  • Dressing for cool to moderate weather – 40 to 65 degrees F. – This is the most difficult weather to dress for. A single layer of clothing is the best bet. Wear either a long sleeve or short sleeve shirt depending upon the exact weather and your personal preference. Shorts are usually warm enough for these conditions. If you prefer a bit more warmth, wear lightweight tights. Running gloves and a headband or hat will provide some added warmth, especially if it is windy. If it is raining wear a water resistant outer layer.
  • Dressing for cold weather – 15 to 39 degrees F. – You will want at least two layers of clothing in cold weather. Start with a long sleeve shirt and heavy running tights. Add a water resistant running jacket for the outside layer. You will definitely want running gloves and a headband or hat.
  • Dressing for very cold weather – Below 15 degrees F. – In this severe weather you will want three layers. Start with a long sleeve shirt and tights made of a wicking fabric. Add an insulating middle layer and possibly some heavy weight running pants and a middle layer for your lower body. Use a water resistant running jacket as an outer layer. Always wear running gloves and an insulating headband or hat in the severe cold.