June 17, 2012— -- A lot of athletes exercise in hot weather and sometimes in extreme heat. Signs of heat exhaustion often begin suddenly. The combination of heat, heavy perspiration, and inadequate fluid intake takes away your body's ability to cool itself and your internal temperature starts to rise, sometimes as high as 104°F. What is a safe body temperature? The symptoms resemble the onset of shock: You feel dizzy, nauseated, or worried. You could have a headache and/or a fast heartbeat.
Don't confuse heat exhaustion and heatstroke. The latter is the potentially dangerous condition, and you get it by ignoring the signs of the former. No one goes directly from feeling fine to the brink of death, no matter how hot it is, so give yourself 30 minutes to respond positively to the following self-care measures. If your symptoms don't improve by then, go to the ER immediately.
Here's what to do for heat exhaustion and how to prevent it.
Get Out of the Heat—Fast!
The obvious answer, but people often ignore it. You need shade or air-conditioning. And after you feel better, know that returning to the sun even hours later can spur a relapse. Be careful.
Drink Cold Fluids
Drinking cold water and sports drinks not only works well for fast hydration, but also will help lower your internal temperature. (You can also reach for one of these 10 Surprising Alternatives to Water)
Cold water on the skin is a big help. Cold water on the skin in front of a fan is even better. Spray it on, drizzle it over your head and neck, or wipe yourself down with cold, wet towels.
Check Your Weight
If you train in hot weather, weigh yourself before and after a workout to see how much water weight you've lost. Then replenish. The next day, weigh yourself again before the workout—and every day thereafter. If your weight doesn't return to your original number or drops further, you may be slowly dehydrating yourself. Make sure you drink enough fluids that your urine runs clear.
Keep Your Shirt On
You pick up more radiant heat exposure with your shirt off. Once you perspire, a shirt can act as a cooling device when the when the wind blows on the wet material
More from Men's Health:
Stay Away from Alcohol
A good summer workout, or even a long round of golf in the sun, may make you feel that it's time for a beer afterward. Watch it. Alcohol dehydrates you and can make even mild heat exhaustion worse. Hydrate first, celebrate later. (And even when you're feeling hydrated, some brews are better than others. Use this list of The Best and Worst Beers in America to determine what you're really getting when you reach for a cold one.)
Mind Your Meds
Certain medications, such as diuretics, blood pressure medicines, allergy meds, cough and cold medicines, can decrease the body's ability to regulate its temperature, increasing your risk. If you have to be on any of those, consider exercising in air-conditioning.
Wait a Week
If you do get heat exhaustion, try to stay out of extreme heat for the next week. You're especially vulnerable to a relapse during that time. Train indoors.
Wait a Week, Part 2
If you train in normal temperatures and know you have a big athletic event coming up in hot weather, give your body time to acclimate to it. Train in that weather for at least a week beforehand. Looking for a new training regimen? Try The Jason Statham Workout—a new routine that helped the action star drop 17 pounds in 6 weeks!
More from Men's Health: