How To Prevent Heat Illness

The best thing about heat illness is that it's preventable. "You simply have to pay attention to how your body feels," says Douglas Casa, Ph.D., A.T.C. "If things feel strange, back off." Here's what happens if you push it too far—and how to bring yourself back.

Heat Cramps

Painful muscle contractions that occur during or after intense exercise

The cause: Muscle fatigue, water and sodium loss

The symptoms: Dehydration, cramps, fatigue

The treatment: Massage, rehydrate

Exercising in high temperatures means more than hydrating properly. Here's a summertime survival guide.

Heat Exhaustion

Inability to continue exercise due to overwhelmed cardiovascular system, depleted energy

The cause: Exercising in hot or humid environments, dehydration

The symptoms: Include fatigue, irritability, nausea

The treatment: Move to shade, elevate legs, apply ice bags, rehydrate

Learn how to adjust your workout to the summer heat from those who know—a Miami running club.

Heat Syncope

Fainting episode that occurs in high temps, typically during initial days of heat exposure

The cause: Coming to a standstill immediately after activity, or standing suddenly or for long periods causes blood to pool in legs

The symptoms: Dizziness, tunnel vision, pale skin, weakness, decreased pulse rate

The treatment: Move to shaded area, elevate legs, rehydrate

You can't outrun the sun, even if you're a sprinter. Here's how best to protect your skin from sun damage.

Exertional Heatstroke

Potentially fatal condition characterized by a core temp of 105°F

The cause: Includes vigorous exercise in a hot environment for more than one hour, poor fitness

The symptoms: Include hyperventilation, disorientation, dizziness, vomiting

The treatment: Full immersion for 30 minutes in cold (35 to 59°F) water