Exercise-Related Heat Illness (Care of the Young Athlete)

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Exercise-related heat illness (ERHI) or
“heat injury” happens 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
    loss.

  • 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

  • Heat (fatigue)
    cramps—
    painful muscle contractions (most often in leg
    muscles), normal temperature

  • Heat exhaustion—body
    temperature up to 104°F; fatigue; nausea; vomiting; dizziness;
    fainting; flushed, moist skin

  • Heat stroke
    (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 Treatment
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.
Heat exhaustion Stop exercising, move to shaded or air-conditioned area. Replace
water loss by drinking a lot of cool fluids. If the athlete does
not quickly improve or is unable to drink fluids, then the
athlete should be immediately taken to the nearest emergency
facility.
Heat stroke Call 911 or your local emergency number. Begin cooling
immediately; 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
    performance.

  • Dripping sweat does not cool the body
    and prevent heat illness; sweat that evaporates does.

  • Children may be at greater risk than
    adults for developing heat illness.

  • Heat stroke is a serious medical
    emergency.

  • 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
    stress.

  • 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
    equipment.

  • 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.