context: Children love to play outside, especially when the weather is warm. Parents, however, should know that active children do not adjust to hot temperatures (greater than 95 ° F) 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 and could lead to dehydration. In addition, kids often don't drink enough to replenish the fluids they lose during prolonged activity since they're too busy having fun. This can lead to severe dehydration and potentially life-threatening heat illnesses. That's why they need adult supervision and plenty of fluids readily available. 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. If your child is overweight or not used to exercise, he should start slowly. 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. Acclimate them to the heat. Gradually introduce young athletes to the heat to prevent dehydration. 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 plenty of water to drink. While sports drinks may be fine for some kids during periods of heavy activity, many contain high levels of sugar as well as the necessary water and electrolytes. Their taste can improve kids' desire to drink, but their use should be limited to periods of exercise only. Children and teens who exercise hard or play sports on hot days 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 -- about every 20 minutes. The AAP recommends five ounces of cold tap water for a child weighing 88 pounds, and nine ounces for a teen weighing 132 pounds. One ounce is about two kid-sized 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 95 ° F 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 dehydration or other problems. 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. Remember that even though kids with moderate heat injuries may look fine 15 minutes after giving them something to drink and allowing them to cool down, they are still dehydrated. Have them take the day off, and keep an eye on them when they go back to practice the next day. Have an emergency plan. Train all support staff in first aid. Make sure each staff member knows what to do during an emergency.