Skip to content

Fitness & Exercise

Heat Exhaustion

Font Size
A
A
A

Risk Factors for Heat Exhaustion continued...

If you live in an urban area, you may be especially prone to develop heat exhaustion during a prolonged heat wave, particularly if there are stagnant atmospheric conditions and poor air quality. In what is known as the "heat island effect," asphalt and concrete store heat during the day and only gradually release it at night, resulting in higher nighttime temperatures.

Other risk factors associated with heat-related illness include:

  • Age. Infants and children up to age 4, and adults over age 65, are particularly vulnerable because they adjust to heat more slowly than other people.
  • Certain health conditions. These include heart, lung, or kidney disease, obesity or underweight, high blood pressure, diabetes, mental illness, sickle cell trait, alcoholism, sunburn, and any conditions that cause fever. People with diabetes are at increased risk of emergency room visits, hospitalization, and death from heat-related illness and may be especially likely to underestimate their risk during heat waves.
  • Medications. These include diuretics, sedatives, tranquilizers, stimulants, some heart and blood pressure medications, and medications for psychiatric conditions.

Check with your doctor to see if your health conditions and medications are likely to affect your ability to cope with extreme heat and humidity.

Preventing Heat Exhaustion

When the heat index is high, it's best to stay inside in air conditioning. If you must go outdoors, you can prevent heat exhaustion by taking these steps:

  • Wear lightweight, light-colored, loose-fitting clothing, and a wide-brimmed hat.
  • Use a sunscreen with an SPF of 30 or more.
  • Drink extra fluids. To prevent dehydration, it's generally recommended to drink at least eight glasses of water, fruit juice, or vegetable juice per day. Because heat-related illness also can result from salt depletion, it may be advisable to substitute an electrolyte-rich sports drink for water during periods of extreme heat and humidity.
  • Take additional precautions when exercising or working outdoors. The general recommendation is to drink 24 ounces of fluid two hours before exercise, and consider adding another eight ounces of water or sports drink right before exercise. During exercise, you should consume another eight ounces of water every 20 minutes even if you don't feel thirsty.

Avoid fluids containing either caffeine or alcohol, because both substances can make you lose more fluids and worsen heat exhaustion. If you have epilepsy or heart, kidney, or liver disease; are on fluid-restricted diets; or have a problem with fluid retention, check with your doctor before increasing liquid intake.

WebMD Medical Reference

Reviewed by Kimball Johnson, MD on September 30, 2012
1 | 2

Healthy Living Tools

Ditch Those Inches

Set goals, tally calorie intake, track workouts and more, all via WebMD’s free Food & Fitness Planner.

Get Started

Today on WebMD

pilates instructor
15 moves that get results.
woman stretching before exercise
How and when to do it.
 
couple working out
Moves you can do at home.
woman exercising
Strengthen your core with these moves.
 
man exercising
Article
7 most effective exercises
Interactive
 
Man looking at watch before workout
Slideshow
Overweight man sitting on park bench
Video
 

Pollen counts, treatment tips, and more.

It's nothing to sneeze at.

Loading ...

Sending your email...

This feature is temporarily unavailable. Please try again later.

Thanks!

Now check your email account on your mobile phone to download your new app.

pilates instructor
Slideshow
jogger running among flowering plants
Video
 
woman walking
Article
Taylor Lautner
Article