Heat Exhaustion Symptoms, Causes, Prevention, and Treatment

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Runners may suffer from heat exhaustion if they don't take precautions when running in the heat. Although heat exhaustion isn't as serious as heat stroke, it's still should be taken seriously. Without the proper treatment, heat exhaustion can lead to heat stroke, which can cause brain damage, and even cause death.Here are the symptoms and symptoms of heat exhaustion, as well as tips on how to prevent and treat it.

Symptoms of Heat Exhaustion

Symptoms of heat exhaustion include fatigue; goose bumps; weakness; headache; dizziness; nausea; vomiting; rapid heartbeat; decreased coordination; possible fainting; and skin that is cool, moist, pale, or flushed.

Cause of Heat Exhaustion

Heat exhaustion occurs when you cannot sweat enough to cool your body. It most commonly happens when exercising intensely in a hot, humid condition. Heat exhaustion is strongly connected to the heat index, which measures how hot it feels when the effects of  humidity and air temperature are combined. The risk of heat-related illness greatly increases when the heat index is above 90 degrees. Runners are most at risk to it when they're racing in hot and humid conditions because they're trying to achieve a specific goal time and often ignore warning signs.

Prevention of Heat Exhaustion

The easiest way to avoid heat disorders is to drink fluids before, during and after exercise.

The body's fluid needs vary with exertion, climate, humidity, terrain, and other factors. The new fluid recommendations say that runners should "obey your thirst" and drink when their mouth is dry and they feel the need to drink. Drink before workouts and make sure you have access to fluids if exercising longer than 30 minutes.

During longer workouts, some of your fluid intake should include a sports drink to replace lost salt and other minerals (electrolytes).

It's also important that runners take weather conditions into account when determining how fast or far they're running. Brutal heat and humidity mean you should scale back your performance goals. Don't try to beat the heat. Hot and humid conditions are not the time to try to push your pace. Slow down, take walking breaks, and save your hard efforts for cooler weather. Stick to the treadmill if you want to run your usual pace and distance.

More: Tips for Preventing Heat-Related Illnesses
Tips for Racing in Hot Weather

Treatment of Heat Exhaustion

If you experience symptoms of heat exhaustion, stop running immediately. Drink cold fluids and get in the shade or an air-conditioned room as soon as possible. Loosen or remove any tight or excess clothing. Other recommended strategies include taking a cool shower, bath, or sponge bath and applying other cooling measures such as fans or ice towels.

If those treatments fail to provide relief within 15 minutes, seek emergency medical help, because untreated heat exhaustion can progress to heat stroke.

Even after you've recovered from heat exhaustion, you'll probably be more sensitive to high temperatures for several days after. Try to stay out of the heat and refrain from doing intense exercise for the next week.


"Exercise and Fluid Replacement", ACSM Position Stand, American College Of Sports Medicine, Medicine and Science In Sports & Exercise, 2007.

MayoClinic.com - Heat Exhaustion

Tamara Hew-Butler, DPM, Joseph G. Verbalis, MD, and Timothy D. Noakes, MBChB, MD, DSc, "Updated Fluid Recommendation: Position Statement From the International Marathon Medical Directors Association (IMMDA)," Clinical Journal of Sports Medicine, 2006;16:283–292)

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