Growing up a few decades ago we thought water was for sissies.  Sports drinks weren’t invented except for maybe Tang and we didn’t even have bottled water.  Occasionally at a picnic someone would bring a big water cooler with a spigot and that was the pinnacle of rehydration.  Thankfully, someone decided that an unnamed team in the South needed replenishment after hours of practice in the hot sun and the world of sports drinks and better hydration was started.

Several noted sports figures have died in recent years from “heatstroke” or heat related illnesses.  What is under appreciated though, is the danger of heat illness in our young athletes.  The dramatic increase in competitive, year round sports for our youth has caused a similar increase in the number of cases of heat related illness.

Children are especially susceptible to heat related problems for several reasons.  Kids have fewer sweat glands than adults, thus limiting the amount of sweat they produce to cool their body.  Their bodies generate more heat than adults and thus increase their core body temperature sooner.  They have a higher ratio of body surface area to body mass.  And as children, are usually dependent on their coaches/parents to provide fluid and shade.

Our bodies, both adults and children, gain heat from internal and external forces.  Internally, we generate heat by the amount of work expended-from couch sitting to being outside running we generate heat.  Externally, our body “gains heat” by the surrounding  temperature.  We lose heat by several mechanisms, the most important being evaporation and radiation.  As our “heat in” exceeds our “heat out”, we run into heat related problems.  Interestingly, when the humidity is greater than 75%, the air is so saturated with moisture that sweat cannot be evaporated.  Thus, high heat, high humidity days are the most dangerous.

Heat related illnesses range from mild cramping to death.  Heat cramps are the earliest sign of a problem with short muscle spasms or cramps that usually last less than a minute.  The legs, shoulders and abdomen are the most common areas to have cramping.  They may also occur during or after exercise.

Treatment for heat cramps includes moving the child to a cooler place, allowed to rest and given fluids.  Fluid support can either be water or electrolyte enriched sports drinks.  Salty foods, such as pretzels or chips, may also aid in recovery as a large volume of salt is lost in sweat.

As practice/play in the heat progresses, so can heat illness.  Heat exhaustion from either excessive water loss or excessive salt loss can occur.  Symptoms of this include nausea, vomiting, headache and fever.  Weakness, dizziness or confusion may also occur in some children.

Treatment for heat exhaustion begins with the same measures as that of cramping with rest, moving to a cooler environment and fluids.  If the child is vomiting, IV fluids may be needed as well as monitoring of labs.

Heatstoke, the most serious heat related illness, is described by high temperatures (above 104.9^o), coma and hot, dry skin.  Seizures, increased heart rate and low blood pressure may also be seen.  This is an emergency and must be treated aggressively by an emergency room.  Untreated heatstroke can lead to total cardiorespiratory collapse and death.

In addition to our children out playing and increasing their chances for heat related illness, children left in cars on a warm day may also suffer.  One report states that an outdoor temperature between 86^o and 104^o can raise the temperature inside a car to 120-140^o within minutes.  Another forgotten danger zone for children are hot tubs and saunas.

Preventative measures go a long way in keeping heat related illnesses away.  Hydrating before activity is recommended.  Urine should be a very light yellow before activities in the heat.  Rehydrating during activity is also paramount.  One recommendation is that a 40 kg child should consume 5 oz of fluid for every 20 minutes of activity and a 60kg child 9 oz/20 minutes.  For activity lasting an hour or less, water is ok.  But, for longer activity, a glucose/electrolyte replacement drink is preferred.

Other helpful hints are to dress your child in lightweight, lightly colored clothing for play.  Also, weighing your young athlete before and after practice can help you estimate how much fluid they are losing.  Adjustments to their rehydration can then be more adequately figured.  Coaches need to be aware of the duration of practice in regards to temperature and humidity. Mandatory water breaks based on those conditions should then be instituted to protect their athletes.