7 Ways to Prevent Dehydration in Children

Children love to play outside, especially when the weather's warm. Parents, however, should know that active children do not adjust to hot temperatures (greater than 95F) as well as adults. Their body surface, as a proportion of their overall weight, is much greater than an adult's. So they produce more heat during physical activity and they sweat less than adults. This reduces their ability to get rid of body heat.

In addition, kids often don't drink enough to replenish the fluids they lose during prolonged activity. This can lead to severe dehydration and potentially life-threatening heat illnesses.

Here are some simple tips to help your child stay safely hydrated while playing outdoors in the heat:

Know the physical condition of the child. Lack of physical fitness can impair the performance of any child who plays in the heat. Dehydration of more than 3% of body weight increases a child's risk of a heat-related illness. For kids participating in organized sports, set practice schedules during cooler hours, especially if the child isn't in great shape.

Acclimatize them to the heat. Gradually introduce young athletes to the heat. Slowly increase the intensity and length of workouts over 10 to 14 days. This helps train their bodies to drink more, increase blood volume, and sweat more. Sweating helps release heat from the body.

Give them water or sports drinks. "The key is water and electrolytes," says Albert C. Hergenroeder, professor of pediatrics at Baylor College of Medicine and chief of the sports medicine clinic at Texas Children's Hospital. Children and teens who exercise hard or play sports on hot days (with temperatures between 79 and 84 F) should cut back their time on the playing field by taking more frequent breaks, according to the American Academy of Pediatrics (AAP). Young athletes should be well hydrated before they begin to play. Then, during play, coaches or parents should make sure children drink often, even if the children aren't thirsty. The AAP recommends five ounces of cold tap water or sports drink for a child weighing 88 pounds, and nine ounces for a teen weighing 132 pounds. One ounce is about two kid-size gulps.

Know the weather conditions, and plan accordingly. Know the heat index: It's the combination of high air temperatures and humidity that's most dangerous. Exercising in a relative humidity of 35% and an air temperature of 95F may cause heat illness. Even dry climates can have high humidity if the sprinkler systems run before early morning practices. Avoid practice sessions during the hottest time of the day. Schedule the hardest workouts for early morning or late afternoon/evening.

Make your athletes wear proper clothing. Lightweight, light-colored clothing is best. Ventilated shorts and t-shirts let heat dissipate. For sports that use heavy equipment and pads, let young athletes practice in lighter clothes for a week to acclimate their bodies. Then put on the bulky gear.

Watch them closely. Watch your athletes before, during, and after practice for any signs of trouble. Pay special attention to athletes who eagerly compete at or above their capabilities.

If a child looks sick, take him or her off the field. Monitor the child closely while the child rests and drinks fluid. "Kids with moderate heat injuries -- not heat stroke, but heat exhaustion -- may look fine 15 minutes later if you give them something to drink and allow them to cool down," says Hergenroeder. "But they're still dehydrated. They should take the day off, and you should keep an eye on them when they come back to practice tomorrow."

Have an emergency plan. Train all support staff in first aid. Make sure each staff member knows what to do during an emergency.

Reviewed by Charlotte E. Grayson, MD.

Published May 2004.

SOURCES: Climatic Heat Stress and the Exercising Child and Adolescent. American Academy of Pediatrics: Committee on Sports Medicine and Fitness, July 2000. Albert C. Hergenroeder, professor of pediatrics, Baylor College of Medicine; chief, the sports medicine clinic, Texas Children's Hospital.