Overheating While Running

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Running offers a number of health benefits when done correctly. Besides knowing how to run, you must also understand when to go for a run. Running in certain extreme weather conditions is safe, if you're prepared. Ignoring safety precautions for running in hot weather can result in a number of serious health problems.


Your body has a cooling mechanism that keeps your core temperature regulated during exercise. It does this by sweating and evaporating water on the surface of the skin. Blood near the skin is cooled and your temperature remains regulated. Your body overheats when oxygen demand forces more blood to rush to the muscles and less toward the skin for cooling. In extremely hot weather, this can raise your core temperature significantly. If you lessen the intensity of your run, more blood is sent again toward the skin for cooling.


The intensity of your run determines, for a large part, how hot your body can get. It is vital that you hydrate yourself when running in hot weather. The more your body works to cool itself, the more it sweats. In the process, you lose valuable fluids. Drinking plenty of water before, during and after a run can help your body stay cool. Aim to drink a cup of water every 15 to 20 minutes while running. The objective for you is to remain hydrated without ever feeling thirsty. Thirst is a sign of dehydration, at which point your body is becoming overheated. Besides drinking water, pour water over your head and neck to cool yourself.

When to Run

Avoid running on extremely hot days. If you do decide to run, don't run between noon and 3 p.m., when temperatures reach their high marks. Instead, opt for a run in the early morning or late evening when temperatures are more bearable. Try to run in shaded areas when you can. Being exposed to intense direct sunlight can cause you to quickly overheat. Running in the morning is arguably the best option, says Jeff Galloway, former American Olympian and the author of "Galloway's Book on Running," as air quality is typically best at this time.


Always apply sunscreen before stepping out in the sun, and wear light-colored running clothes made from microfiber material. This type of material breathes more easily than cotton, which can help you stay cool. Wear some head protection, such as hat or visor.

Warning Signs

Stay alert when running in the heat. If your muscles begin to cramp or spasm, stop running immediately and begin to hydrate. Should you feel lightheaded and nauseous, you may be experiencing heat exhaustion. Vomiting and coordination problems are other signs of heat exhaustion. You should stop exercising and go into a cool environment immediately while hydrating. If you experience a heat stroke, indicated by a body temperature of 106 degrees F or higher, seek medical attention right away. Heat strokes can be fatal -- go inside immediately and remove your clothing to help cool your body. Apply ice packs to your neck and underarms, and take in plenty of fluids.