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Intrinsic and extrinsic factors can place an athlete at higher risk for an exertional heat stroke. Knowledge of these is beneficial in that greater precautions can be taken for those with multiple risk factors. Some of these pre-disposing intrinsic factors include a past history of exertional heat illnesses, inadequate heat acclimatization, low fitness level, and an overweight or obese body composition. Some pre-disposing extrinsic factors include a high environmental temperature, humidity, and/or sun exposure during exercise, intense or prolonged workouts with minimal breaks, and equipment that limits sweat evaporation. For a more comprehensive list of these risk factors, please see this website.

Immediate and accurate recognition of exertional heat stroke is critical to the athlete’s survival. There are many signs and symptoms associated with this life-threatening heat illness; however, there are two main criteria used for diagnosis. These include a rectal temperature greater than 40°C immediately post collapse and central nervous system dysfunction such as irrational behavior, emotional instability, collapse, coma, and dizziness. These two criteria should be used when assessing an athlete suspected of an exertional heat stroke. If a rectal thermometer is not readily available, a core body temperature should not be taken using an alternate, less accurate device. Instead, the medical professional on-site should use other signs and symptoms to aid in diagnosis such as confusion, nausea, vomiting, and rapid pulse, as well as assessment of the environmental conditions, workout intensity, availability of water, and athlete’s physical fitness level, to name a few. For more information on recognition of exertional heat stroke, please see this video produced by USA Football and the Korey Stringer Institute.

Quick and effective treatment of exertional heat stroke can save an athlete’s life. This heat illness is 100% survivable if treated appropriately. The gold standard for cooling an athlete diagnosed with exertional heat stroke is cold water immersion. This involves placing as much of the athlete’s body as possible into a large tub filled with ice cold water. Constant stirring of the water, monitoring of vital signs and rectal temperature, as well as central nervous system assessment all done by a certified medical professional will help to ensure a safe recovery. Upon the athlete’s collapse, this treatment of cold water immersion should begin as quickly as possible. There is a 30-minute window of time in which the athlete must begin cooling to ensure their survival. Once cooling has begun, EMS should be activated while cooling continues until their arrival. It is crucial that those treating the athlete always remember: cool first, transport second. For more information on treatment of exertional heat stroke, please see this video.

In order to prevent the occurrence of this serious heat illness, precautions can be taken to help ensure safety. One of the best methods of prevention is heat acclimatization. This is a process of gradual increases in duration and intensity of conditioning workouts prior to the start of a season. This allows the body to develop physiological adaptations to the heat, thus aiding in protection. In addition, a certified medical professional such as an athletic trainer should be present at all workouts. This will ensure that proper guidelines are followed and treatment is readily available. Proper hydration prior to, during, and after exercise can be assessed by observing urine color, calculating your individual sweat rate to determine the amount of fluids needed, and constant awareness of drinking water throughout exercise, especially in extreme environmental conditions. In addition, wearing loose-fitting and absorbent clothing can help sweat to evaporate and thus cool your body. There are many other ways in which exertional heat stroke can be prevented, and a more comprehensive list can be found on the Korey Stringer Institute website.

The 5 pillars of exertional heat stroke prevention

How to assess the color of your urine

How to calculate your sweat rate

Guidelines for preseason heat acclimatization
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Lesson Creator
New York, NY
07/07/2014 • 
 27 Responses
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