Avoid Heat Illnesses While Exercising

The sun's warmth is awesome, but being active in the heat can be trouble. Whether you're a serious athlete, a weekend warrior or you love do-it-yourself lawn care, heat-related illnesses can sneak up on you.

A Franciscan Health Sports Medicine athletic trainer shares what you need to know about heat-related illnesses, so that you don't get sidelined.

How Does Heat Affect Your Body?

Your body has natural cooling systems. Sweat, which cools the body as it evaporates on your skin, is one. Heat also escapes your body when more blood goes to your skin, arms, legs and head when you exercise.

But high air temperatures, humidity, heavy sweating and a lack of fluids stress those systems. Body heat gets trapped and pushes your body temperature higher.

What Are Heat Illnesses?

Heat illnesses are conditions that develop when your body can't cool itself. Heat illnesses start mild but become life-threatening if not treated. They include:

• Heat cramps—Painful muscle spasms that signal your body's overheating.
• Heat exhaustion—Clammy skin, heavy sweating and nausea that develop when your body temperature climbs as high as 104 degrees.
• Heat stroke—A life-threatening emergency that can shut down basic body functions.

Young children and adults over age 65 are more susceptible to heat illness because their bodies can't get rid of heat as easily. Other things that make it harder for your body to cool down are:

• Being dehydrated before you even begin exercising
• Certain medicines, such as antihistamines and stimulants
• Higher percentage of body fat
• Not being used to a hot environment
• Poor physical shape
• Using alcohol before and during exercise

What Are Warning Signs Of Heat Illnesses?

Your body sends signals when it's overheating, telling you to back off. Ignoring them can be deadly.

Each year, an estimated 240 people die from heat-linked illnesses, and heat stroke is the third-ranked cause of death for young U.S. high school athletes.

Signs of heat illness while exercising

If you start having muscle cramps while exercising, it's a sign you're getting dehydrated. Without easing up and drinking water, you're at risk for heat exhaustion, which can include some or all of these symptoms:

• Cold, pale and clammy skin
• Dark urine
• Dizziness
• Heavy sweating
• Headache
• Muscle cramps
• Nausea or vomiting
• Thirsty
• Weakness

Ignoring the signs of heat exhaustion can lead to heat stroke, when internal organ damage starts. Symptoms of heat stroke can include:

• Confusion, disorientation
• Dizziness
• Fast, strong pulse
• High body temperature
• Hot, red, dry skin after sweating
• Headache
• Losing consciousness
• Nausea

How Do You Treat Heat Illnesses?

Treating heat illnesses is all about cooling the body. Get out of the sun and sit in front of a fan. Sip water and remove extra clothing or equipment to expose skin to the air. You can also place ice packs or cool, wet cloths on your body or douse yourself with water from a hose or a shower. Immersing in cold water, such as a tub or tank with ice if possible, is the most effective cooling technique. Changing out cold, wet towels placed on the body, and ice in the groin and armpits also can help. 

If your condition progresses to heat stroke, it's a medical emergency and warrants a 911 call.

How Can You Avoid Heat Illnesses?

"Heat illnesses are 100% preventable," said Franciscan Health athletic trainer Paul Herman. The key is being proactive before exercise.

Get Your Body Ready for Exercising in the Heat

Slowly progress exercise time and intensity to allow the body to get used to and be more efficient at sweating. Start with 20 minutes and work up to an hour. Then, increase the intensity of your workout. Student-athletes may also progressively add equipment, such as helmets and pads. 

Stay Hydrated

Drink before, during and after exercise—water is best. Measure your hydration by weighing yourself before and after exercise. Drink enough to get back the weight you lost (it's just water weight). When your urine is colorless to light yellow, you're on track.

Use Heat Stress Tools

Sweat doesn't evaporate as well with humidity, and the body overheats. The heat index factors heat and humidity together to tell you how hot it really feels. Check the numbers to know when you should back off outdoor activity. School athletic trainers use the Wet Bulb Globe Temperature (WBGT), which includes wind and other variables to determine when practices need to be modified due to heat.

When Is It Too Hot To Work Out Outdoors?

You probably check the regular temperature on your phone's weather app, but that number doesn't tell the whole story about how hot it really feels.

Even the heat index, which factors air temperature and humidity, only begins to tell the story.

“The Wet Bulb Global Temperature is the gold standard for helping with heat-related illness,” said Herman, an athletic trainer at Mooresville High School. “It’s a research-driven temperature that helps us determine whether it’s safe for athletes to practice outside or not.”

The wet bulb temperature is a special measurement that combines:

• Regular air temperature
• Humidity (how much moisture is in the air)
• Wind speed
• Sun angle and cloud cover

Think of the wet bulb temperature as the "feels like" temperature for athletes who are working hard and sweating. When humidity is high, sweat doesn't evaporate from the skin as easily. This makes it harder for the body to cool down.

The device gives a reading that helps athletic trainers follow safety guidelines when it comes to organized sports. Different readings mean different safety steps, Herman explained.

Below 82.0°F: Regular activity is usually safe, but athletic trainers still watch athletes carefully.

82.1°F - 86.9°F: Athletic trainers will:

• Make water breaks longer and more frequent
• Allow athletes to remove unnecessary equipment
• Watch closely for any signs of heat problems
• Consider moving practice to a cooler time of day

87.0°F - 89.9°F: Athletic trainers take stronger steps:

• Football players practice without helmets and pads
• Athletes should take rest breaks every 15-20 minutes
• Practice time might be cut short
• No intense conditioning drills

90.0°F and above: The most serious level:

• Outdoor practices may be cancelled
• Activities might move indoors
• All equipment and helmets are removed
• Practice time is greatly reduced

These rules for following wet bulb temperatures help make sure no athlete gets dangerously overheated, but people who may be less fit or have conditions who may put them at higher risk of heat illness may need to limit their activity more.

After Heat Illness, Return To Exercise Gradually

For heat exhaustion, take a day off and go for a walk outside the next day. By the third day, you may be ready for regular activity. 

Heat stroke requires a physician's okay to return to exercise. It will take about a month to return fully to exercise: a week off, then easy exercise indoors, moving outside with easy activity, then exercising more strenuously.

Get the support you need to return to regular exercise to improve your health and performance. Whether you're a weekend warrior or a serious athlete, members of the Franciscan Health sports medicine team can help you make a safe transition.