Exercise-Related Heat Illness (Care of the Young Athlete)
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Exercise-related heat illness (ERHI) or
"heat injury" can occur when exercise is done in high temperature
and high humidity. It's one type of injury, unlike sports injuries caused
by contact, that can almost always be prevented with proper attention to safety
and common sense.
About body temperature
Human bodies try to keep a constant body
temperature of around 98.6°F by balancing heat gain with heat
Exercising muscles create 10 to 20 times
more heat than resting muscles.
Sweating is the main way the body gets
rid of excess heat.
As humidity rises, sweating becomes less
effective at cooling the body.
Body temperature will rise if the body
is unable to get rid of excessive heat, resulting in heat illness.
Signs of ERHI
cramps—normal body temperature; painful muscle contractions (most often in leg
temperature up to 104°F; fatigue; nausea; vomiting; dizziness;
fainting; flushed, moist skin
(life-threatening)—body temperature greater than
104°F, confusion, combativeness, seizures and/or stroke, shock,
coma (unresponsive), and/or heart failure/cardiac arrest
Emergency on-site treatment
Immediate treatment should include cooling the body and replacing fluids
(cool water or an appropriate sports drink).
|Type of illness
|Heat (fatigue) cramps
||Stop exercising. Massage or stretch involved muscle. Replace
salt and water loss by drinking a lot of cool, salt-containing
fluids. Future cramping may be reduced by improved conditioning,
getting more used to exercising in hot temperatures, and
drinking more salt-containing fluids.
||Stop exercising. Move to shaded or air-conditioned area. Replace
water loss by drinking a lot of cool fluids. Cool with ice packs or cold water immersion. If the athlete does
not quickly improve or is unable to drink fluids, then the
athlete should be immediately taken to the nearest emergency
||Call 911 or your local emergency number. Begin cooling
immediately with cold water immersion; don’t wait for help to arrive. The athlete
needs immediate medical attention.
Facts about heat illness
Even the best-trained athlete can
develop a heat illness when it is hot and humid.
Early recognition is the key to
successful treatment of heat illness.
For most athletes, drinking cold water
is as good as sports drinks in preventing heat illness and maintaining
Dripping sweat does not cool the body
and prevent heat illness; sweat that evaporates does.
Heat stroke is a serious medical
Plans should be in place to cancel,
postpone, or change events if it's too hot and humid.
Both temperature and humidity (heat
index) must be measured to accurately assess environmental heat
Athletes who have had heat illness
before are at higher risk for another episode.
Tips to help prevent heat illness
Schedule activities during the coolest
parts of the day (early morning or late afternoon/evening); consider
cancelling or delaying an activity under extreme conditions.
Allow athletes to gradually adjust to
exercising in hot, humid weather by increasing activities slowly over
the first 2 weeks of practice.
Avoid the use of excessive clothing and
Schedule breaks every 10 to 15 minutes
during any activity that lasts longer than 1 hour.
Weigh athletes before and after each
activity. Athletes should replace all of their weight lost during any
exercise period prior to the next exercise period.
Know the signs and symptoms of ERHI.
Make sure plenty of cold water and
sports drinks are available before, during, and after each activity.
Encourage athletes to drink 4 to 8
ounces every 15 to 20 minutes during any activity period.
Encourage athletes to eat a balanced
diet that provides the necessary vitamins and minerals.
Identify athletes at high risk, such as
athletes who are obese, are poorly conditioned, are not acclimated, have
a current illness, are taking certain medicines, or have a history of
previous heat-related problems.
Plan for emergencies—measure body
temperature, call 911, cool immediately.