Heat Illness

There are many important differences between an adult and a young athlete. Physiologically, children conduct more heat from the surrounding environment than adults do because of a greater ratio of surface area to body mass. In addition, children generate more metabolic heat per weight than adults, but are less capable of releasing heat because of a lower sweating capacity.28 For these reasons, children are more susceptible to heat illnesses in sports.

Heat stroke, a heat illness related to the body's inability to regulate temperature, has become the third-leading cause of death in youth athletes.29 As coaches, parents and players, we need to educate ourselves to prevent this from occurring, as it is largely preventable with appropriate precautions and response.


Preventing Heat Illnesses

Knowing the Danger Zone

An important part of coaching is understanding the conditions that present a greater risk to the young men and women in your care. As a general guideline, temperatures ranging from 65 degrees to 72 degrees Fahrenheit present a moderate risk, temperatures of 74 degrees to 82 degrees present a high risk, and temperatures above 82 degrees present an extremely high risk to athletes.30 In addition, an increase in humidity greatly increases the chance for heat illness.

In high-risk conditions, coaches are encouraged to conduct shorter practice sessions. Wearing less padding and equipment is also an important consideration based on weather. A 10-day period of lighter practices is recommended, especially in warm weather climates, for athletes to become properly acclimated. Coaches should continuously observe athletes for any heat illness symptoms and should not hesitate to take an athlete aside and evaluate their condition. During conditioning drills, a buddy system may be helpful so that teammates may monitor tolerance.

Coaches should also be aware of high-risk candidates for heat illness, which include athletes who have a history of a heat illness-related event; are overweight/obese; have a history of diabetes, renal or heart difficulties; have had a recent bout of flu or upper respiratory infection; have anorexia or bulimia; or have a poor baseline fitness level. Some athletes intentionally make themselves far more prone to heat illness, such as wrestlers who are trying to "make weight."

Heat illness can be managed through proper hydration before, during, and after practice. Heat illnesses stem from the loss of fluids and electrolytes during sweating. Replacing them on a consistent basis is one of the most effective ways to remain hydrated. It is recommended that coaches eliminate voluntary hydration by athletes and instead enforce hydration beyond thirst levels on a routine basis (e.g., every half hour).

An estimated 70 percent of high school athletes show up for practices inadequately hydrated. The STOP Sports Injuries campaign recommends the following guidelines for keeping athletes hydrated.33

  • Stay hydrated throughout the week, especially on practice and game days
  • Drink 16 ounces of water or sports drink one hour before warming up for play
  • Continue with 4–8 ounces of fluid every 15–20 minutes of play
  • Consume food or drink with a moderate amount of sodium (salt) prior to competition or training
  • For games and practices lasting longer than one hour or for multiple practices in one day, replacement fluids should contain sodium, potassium, and carbohydrates
  • Weighing yourself before and after sporting events is a good way of judging how much fluid is lost while exercising. If more than 2 percent of body weight is lost during play, the athlete may be compromising performance and should increase fluid intake. If the athlete is gaining weight, fluid intake should be lowered
  • Try to keep urine at a lemonade coloration or clearer
  • Practice at cooler times of day (i.e., early morning, later afternoon)
  • Discourage athletes from wearing layered or rubberized clothing that prevents the body from cooling down efficiently
  • Remember that every athlete's body is different; what works for one athlete may not work for another

Proper training in the months leading up to practice is another effective way to acclimate the body to warm temperatures. Athletes often do not adequately prepare for the upcoming season, and therefore shock their bodies once training begins. Athletes must gradually condition themselves for competition in extreme temperatures.

In addition, parents, players and coaches must monitor other player's mental and physical condition to detect early signs of heat illness. Always be aware of the limitations caused by warm weather.

Recognizing Heat Illnesses

Common heat-related illnesses include the following.

  • Heat Cramps: Cramps caused by the depletion of salt and water in the body due to profuse sweating
  • Heat Exhaustion: The result of either water or salt depletion in the body due to profuse sweating during prolonged exercise, commonly causing athletes to feel weak, dizzy, nauseous and confused or to have headaches
  • Heat Syncope: A precursor to heat stroke, caused by prolonged exercise in the heat, which can also occur after physical activity has stopped—usually within the first week of acclimating to exercise in the heat. Symptoms include weakness, fatigue, tunnel vision, and fainting
  • Heat Stroke: The most severe heat illness is caused by the body's failure to cool itself down. It can occur suddenly with few preceding symptoms, causing unconsciousness, coma, or death

Cold-Related Illnesses

Cold weather, as well as heat, can lead to dehydration. Recent studies suggest that cold weather decreases the thirst sensation in athletes. Athletes competing in colder weather do not feel the desire to hydrate nearly as much, but they exert similar effort and lose fluids and electrolytes at a similar rate as they would in warmer temperatures. Athletes competing in cold weather need to take the same precautions for staying hydrated.


Responding to Heat Illness and Dehydration

When heat illness and/or dehydration is suspected, immediately remove the child from play. It is recommended to have a plan in case of emergency, including how to contact medical professionals (i.e., phone numbers, contact names) and possible treatment options (e.g., ice packs, spray bottles and towels) readily available. Take these recommended steps when assessing an athlete with heat illness and dehydration symptoms.

  • Get the athlete to a cool and shaded area
  • Have the athlete drink water or a sports drink
  • Elevate the athlete's legs slightly
  • Do not return the athlete to any physical activity
  • If symptoms are severe or if the child is unconscious, call 9-1-1 and seek immediate medical aid. Keep the athlete cool using cold water immersion, a cold water spray, cold towels placed over the entire body or ice packs
  • Inform the parent (or guardian) of the athlete for continued, effective monitoring if they are not present during an event

The tables on the following pages summarize additional actions to take and be aware of when responding to heat illness and dehydration issues.


Comparison of Heat Illness Characteristics in Youth with those of Adults31

Characteristic Typical for a Child vs. Adult
Sweating threshold Higher
Sweating rate per m2 skin Much lower
Exercise tolerance Shorter
Acclimation to heat Slower
Core temperature increases with hydration Faster


Symptoms of Dehydration per Percent Body Weight Lost32

% Body Weight Lost Symptoms
0.5 Thirst
2.0 Increased thirst, discomfort and poor appetite
3.0 Dry mouth and decreased urine output
4.0 Flushed skin and impatience
5.0 Poor concentration
6.0 Decreased temperature regulation
8.0 Dizziness, labored breathing and confusion
10.0 Poor balance, delirium and swollen tongue
11.0 Kidney failure and circulatory insufficiency


Dehydration Symptom/Treatment Chart33

Symptoms Disorder Treatment
Thirst, nausea,
chills, clammy skin,
muscle pain/spasms
Heat cramps 4-8 oz cold water
every 15 minutes;
shade and remove
excess/wet clothing
Decreased sweating,
dizzy, headache, short
of breath, rapid pulse,
decreased saliva and
increased fatigue
Heat exhaustion Stop all exercise, ice
bag to top of head
and 16 oz of cold
water for every
pound lost.
Decreased sweating,
decreased urine, dry and
hot skin, swollen tongue,
hallucination, rapid pulse
unsteady gait, fainting,
hypotensive, loss of
consciousness, shock
Heat stroke Emergency medical
treatment, ice bath
or shower and
elevate the feet


Coaches, parents and players must not underestimate the seriousness of heat illnesses. These illnesses can happen suddenly with little warning and can have severe consequences. Through gradual acclimation to warm weather, proper hydration and continually educating ourselves on heat illnesses, we can help young athletes play safe in the heat.