Playing outside in all types of weather and temperatures is very healthy and promotes the well being derived from exercise. However, the body needs to adapt to changes in temperature and necessary precautions taken during hot or cold temperatures are important to avoid problems. Avoiding heat-related problems in hot weather is just as essential as avoiding frost bite in cold weather.

It is interesting how people in different areas of the country deal with extreme temperatures. Those living in cold areas think nothing of bundling up and going out in the snow, while in the southwest, playing outside in 90°F plus weather is the norm. Yet, switch people from one area to another, and they would not think of letting children play outside.

The main concern with regard to heat is the body's core heat. For instance, marathon runners may raise their body temperature to more than 104°F. Exercising the muscles generates 15 times the amount of heat as that of resting muscles. Direct heat (sunlight) and reflected heat (from sand, sidewalks, artificial surfacing, etc.) will increase the heat surrounding the body. This means that the body cannot dissipate, or lose, the heat it generates naturally and from exercising. The best way to cool off is through the skin; evaporating water cools the skin, cooling the blood in our vessels in our skin, and thus cooling the body. Air movement and water (as in a swimming pool) are ways to improve this cooling mechanism.

Heat illness can happen when the body is unable to cool off. Factors that commonly lead to heat illness in children include:

• Overdressing (wearing too many clothes).
• Running or playing vigorously in extremely hot weather.
• Not drinking enough fluids, especially water.
• Being left in an extremely hot environment, such as in a hot vehicle. Even with the windows down, the inside temperature of a vehicle can quickly reach 120°F.

There are three main forms of heat illness. Heat cramps are brief, severe cramps that usually affect the leg, arm, or abdomen, and may occur during or after playing or exercising in extreme heat. These are painful but not serious. Children are most likely to get heat cramps when they have not been drinking enough fluids. To treat, move the child to a cool place, allow him to rest, and give fluids (water) to drink. Massaging the cramped muscles may also help.

Heat exhaustion is a more severe heat illness. Symptoms may include fatigue, weakness, headache, nausea and/or vomiting, and clammy skin (from sweating). Immediately move the child to a cool area, loosen or remove clothing and sponge the child's body with cool water, give fluids (water) to drink, and allow the child to rest. Contact your health consultant or a physician, and call the child's parent. Cooling the body is essential, because if left untreated, the child's body temperature may continue to rise, resulting in heat stroke.

Heat stroke is life threatening. Symptoms may include headaches, dizziness or weakness, disorientation, agitation, or confusion, sluggishness or fatigue, or seizure. With heat stroke, the skin is hot and dry skin. Body temperature can quickly rise to 105°F or higher and the child can go into shock or coma. Call for emergency help and while waiting, cool the body fast! Get the child to a cool place, remove clothing, and sponge or douse the body with cool water.

Preventing heat illness

The main way to prevent heat illness in children or adults is by using common sense.

• Drink plenty of fluids, especially water. The body does not use thirst to indicate you are becoming over heated, so constant fluid intake prior to and during exercise is necessary. "No pain no gain" has led to many catastrophes with heat-related illnesses. Sports drinks may increase children's desire to drink because they taste good, but they should be diluted by half with water. Sodas and fruit drinks contain too much sugar, and beverages with caffeine actually cause the body to lose fluid.
• Dress children appropriately in cool clothing. Wide-brimmed hats provide "wearable shade."
• Keep children inside or in the shade during the hottest part of the day (10:00 a.m.-2:00 p.m.).
• Be aware of any preexisting medical conditions which may cause a child to be more heat sensitive.
• Pay attention to weather conditions, including the humidity. Parents and caregivers need to understand the "heat index" which correlates temperature and humidity with the body's ability to cool itself. This means that while the actual air temperature may be 90°F, it may feel like 105°F to your body!
• Be aware of the signs and symptoms of heat illness and take immediate action to cool the child.
• Never leave a child (or adult or pet) in a hot vehicle!

Children can safely play outdoors on hot days provided that precautions are taken. Understanding weather conditions, using shaded areas along with proper clothing and sun screen, and ensuring that children drink plenty of water are important steps to prevent heat-related illness. When the weather conditions put children at risk, take the children outside in the early morning hours and reserve the hottest times of the day for inside activities.

By: James M. Poole, MD, FAAP

INTERNET RESOURCES

www.nlm.nih.gov/medlineplus/heatillness.html

www.kidshealth.org

www.ehow.com/eHow/eHow/0,1053,7177,00.html