Brrrrr…so far it’s the third coldest winter here in the inland Northwest. So how do you exercise safely in this cold winter weather? You want to prevent hypothermia or frostbite due to excessive loss of body heat. The cold can also cause a generalized vasoconstriction, which can increase blood pressure. This can be a problem for people who are hypertensive or who have heart disease.
Heat loss can increase when there is a strong wind, making the windchill factor a major concern.
Before exercising in the cold, consider the following tips:
- Wear several layers of clothing, so that garments can be removed or replaced as needed. As exercise intensity increases, remove outer garments. During periods of rest, warm-up, cool-down, or low-intensity exercise, put them back on. A hat is also important, since body heat radiates from the head.
- Allow for adequate ventilation of sweat. Sweating during heavy exercise can soak inner garments. If evaporation does not readily occur, the wet garments can continue to drain the body of heat during rest periods, when retention of body heat is extremely important. If there is wind, it is better to begin a round of exercise going into the wind and finish with the wind at your back. If the opposite occurs, you can become sweaty when moving with the wind, and then have to return against the wind while facing increased heat losses from the effect of wet clothing.
- Select garment materials that allow the body to give off body heat during exercise and retain body heat during inactive periods. Cotton is a good choice for exercising in the heat because it readily soaks up sweat and allows evaporation. For the same reasons, cottons is a poor choice when exercising in the cold. Wool is an excellent choice when exercising in the cold because it maintains body heat even when wet. Newer synthetic materials, such as polypropylene, are excellent choices, as they wick sweat away from the body, thereby preventing heat loss. When windchill is a problem, nylon materials are good for outerwear. Synthetic materials like GoreTex® are probably the best choice for outerwear because they can block the wind, are waterproof, and allow moisture to move away from the body.
- Replace body fluids in the cold. Fluid replacement is important when exercising in cold air. Large amounts of water are lost from the body during normal respiration, and this effect becomes magnified when exercising.
- Monitor body weight over several days, as sweat losses may not be as obvious as when exercising in the heat.