Raleigh, N.C. — Doctors at WakeMed say the best way to keep active children both cool and safe in hot weather is water – lots of water.

"Right now, it's fun to be outside, so kids are out running around, having fun but not drinking fluid," said Dr. Graham Snyder. Interactive     Stay safe in hot weather

He explains the situation to his children like he does his patients.

"I say you have to have a certain amount of energy in your body, and you have to keep that at a certain temperature," he said.

Playing in water is good. Drinking water is even better for prevention of heat-related illnesses.

"The most common this is a combination of being overheated and dehydrated," Snyder said.

Over the past week, Rex Hospital in Raleigh had seen 10 cases of heat-related illnesses in its emergency department. At WakeMed emergency rooms across Wake County, 38 people visited with heat-related symptoms.

Children and the elderly can be even more susceptible to the impact of heat. Parents should keep an eye out for red skin, leg cramps, nausea and vomiting. 

John Hammes said he rations his son's time outdoors when the temperature soars.

"Maybe 30 minutes out in the heat, 30 minutes inside where it's cool. The key thing is to make sure they're inside part of the time and outside part of the time," he said.