Running in hot weather can be risky, if not fatal. When running in hot weather, there are many factors in avoiding heat stroke. Factors like air temperature, clothing, running pace and distance, body weight, hydration, heat acclimation, and individual predisposition to heat stroke can all impact your chances of being affected by it.
Symptoms
If your body's release of excessive heat during running does not exceed the air temperature, heat stroke becomes possible. Mental condition decreases rapidly, and most of the body's blood is pumped to the surface of the skin to release heat. This causes a degraded thought process, possible loss of consciousness and or convulsions. Tim Noakes, M.D., notes in his book, "Lore of Running", that a body temperature of more than 107 degrees F is a sure sign of heat stroke, as are a heart rate of more than 100 beats per minute, and rapid breathing.
Causes
Dr. Noakes notes that the rate of heat loss from a runner's body is controlled by air temperature, humidity, and wind. Running in very hot conditions causes your body's rate of heat production to exceed the rate of heat loss. Your heat production when running is determined by your body size and pace. The larger you are and the faster your pace and effort, the more your heat production.
Remedies
"The Complete Book of Running" by Jim Fixx, suggests dressing lightly in light-colored clothing, and staying hydrated with water or sports drinks. Douse yourself with water as much as possible to increase the cooling effect. The argument of whether it is better to put liquid in you or on you is ongoing; however, both Dr. Noakes and Fixx endorse the dousing effect to stay cooler.
More Remedies
Fixx recommends 7 to 10 days of acclimatizing to hot conditions. This allows your body to adapt, producing a lower heart rate and a higher amount of sweat production. He also notes that lessening your pre-race warm-up will help. If you have an important race coming up in a hot climate, get there at least a week in advance to acclimate to the conditions.
Treatment
Dr. Noakes recommends immediately trying to lower the body temperature of the runner. Place him in a shaded, cool area, and remove clothing. Spray cold water on him, then use cold, wet clothes and ice packs. Try to bring the runner's body temperature to below 100 degrees F. It is critical to monitor his temperature for upward spikes. If this occurs, repeat the cooling treatments.
Cautions
The symptoms for heat stroke can sometimes be easily misdiagnosed. A heart attack victim will have little or no pulse and no breathing. A heat stroke victim will have the rapid heart rate and breathing. The symptoms of hypoglycemia or low glucose levels, which can be confused with heat stroke, are a temperature of below 105 degrees F, and low glucose measurements. It is important for races to have trained medical staff to quickly identify heat stroke symptoms and perform quick and proper treatment. Dr. Noakes concludes that some runners are simply predisposed to heat stroke, perhaps for hereditary reasons.
References
- "The Complete Book of Running"; Jim Fixx; 1977
- "Lore of Running"; Dr. Tim Noakes; 1991
