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Keeping Cool When The Weather Is Hot

It's summertime and you head out for a run. Before you even finish the first mile, your body feels as though it might ignite from the heat. It's not your imagination. Fifteen minutes into your run and your body temperature could be as high as 5F above normal. If you were to continue at this pace, fatigue and heat illness would no doubt take over.

Strategies To Protect Yourself From Heat Illness

The above scenario doesn't have to happen. Drinking enough fluid, whether it be water or a sports drink, is imperative for exercising in hot or humid weather. Maintenance of body fluids is essential to maintaining proper body temperature. Sweat dispels heat through your skin. If you let your body become dehydrated, you'll find it much more difficult to perform even the lightest of workouts. But don't wait until you're thirsty to start replenishing those fluids. Chances are, by the time you actually feel thirsty, your body is well on its way to becoming severely dehydrated. The following strategies will help you protect yourself from the onset of heat illness:

     Hydration Fluid replenishment before, during and after exercise is essential to avoid progressive dehydration. Always consume more fluids than you think you need before and after exercise, and strive to drink six to eight ounces of fluid every 15 to 20 minutes during exercise.
  Exercise Intensity You should probably reduce the intensity of your workout, particularly the first few times you are exposed to higher temperatures.
  Temperature Use the heat stress index table to determine the risk of exercising at various combinations of temperature and humidity. While a 90F outdoor temp is relatively safe at 10 percent humidity, the heat stress of 90F at 50 percent humidity is the equivalent of 96F. When the heat stress index rises above 90F, you may want to consider postponing your exercise session until later in the day. Or, plan ahead, and beat the day's heat by working out early in the morning.
  Fitness Physical training and heat acclimation can increase your blood volume, helping to regulate body temperature more effectively. Interestingly, the acclimatization process can be completed in 7 to 14 days of repeated heat exposure. However, you must always continue to drink fluids before, during and after exercise.

  Clothing Wear minimal clothing to provide greater skin surface area for heat dissipation. Your clothing should be lightweight, loose fitting, light colored to reflect the sun's rays, and of a material that absorbs water, such as cotton.

  Rest Know when to say 'no' to exercise. Using common sense is your best bet for preventing heat stress when Mother Nature turns up the heat.

Heat Sensation Risk of Heat Injury

90 - 105
Possibility of heat cramps
105 - 130
Heat cramps or heat exhaustion likely.
Heat stroke possible.
Heat stroke a definite risk

This article has been supplied courtesy of the American Council on Exercise, one of FoodFit's Resource Associations.

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