I have a client who is moving to Alaska and is worried about continuing her long distance running training in such a cold climate. Is there a temperature below which you should not exercise outside? Do you have any tips on how to train in the cold? Thanks very much.
For the majority of people, the body responds very well to cold environments. The retention of metabolic heat is the primary goal, and the body will do this by constricting the blood vessels to reduce heat loss and increase metabolic heat production through shivering.
There are some difficulties and challenges when exercising in the cold, which include body cooling or wearing insulative clothing. Shivering increases the metabolic cost during exercise, which means the person will be less efficient throughout the exercise session due to a higher volume of oxygen being used. Pertaining to clothing, many people attempt to stay warm by adding extra clothing, but this practice must be carefully navigated. Caloric expenditure increases as the weight of the clothing increases, which leads to a further loss of metabolic heat from the body.
I am not familiar with a certain temperature when people should not exercise outdoors as it will depend on the level of acclimatization, adaptation, clothing and individual response. Alteration of fuel (carbohydrate) supply also happens as stored glycogen will be used at a faster rate when fast-twitch muscle fibers are recruited (due to a decrease in maximal contractile forces of skeletal muscle in the cold). This could affect exercise performance as well as cognitive function during exercise in the cold since the brain utilizes glucose primarily, which will also be decreased.
Similar to going to altitude, many individuals can acclimate to a cold environment with time, and exposure should begin with lower volume and intensity and gradually increase over time. The following tips may be useful when traveling to a cold environment and continuing long distance run training:
- Do not wear too tight of clothing that would restrict circulation. Be sure to exercise the hands, feet and face periodically to promote adequate blood flow to these extremities.
- Dress in windproof clothing if the wind is strong and choose mittens instead of gloves.
- Wear a good quality sock that transfers moisture from the foot to the shoe to prevent wet feet.
- Protect the feet from getting snow in the shoes by wearing running gaiters.
- Protect the legs and genitals with tights or performance long underwear.
- When possible, do not run into a cold wind when clothing becomes soaked from sweat. Plan the run route based on wind direction.
- After the run, cool down in a warm environment or put on dry clothes.
An excellent resource is the book, “Performing in Extreme Environments,” by Lawrence E. Armstrong published by Human Kinetics in 2000.