It's important that kids don't turn into couch potatoes over the summer, but that doesn't mean they should be outside all day, every day, particularly in the middle of a heat wave. Young children in particular are at risk for heat exhaustion and heatstroke, both of which cause the body's cooling system to shut down. Symptoms of mild heat exhaustion include fatigue, cramps and thirst, while more serious cases are indicated by dizziness, nausea and rapid heartbeat.
The most important weapon in the fight against heat exhaustion and heatstroke is water, and plenty of it. Children should drink a glass before they head outside, and once outdoors, they should have a water bottle that they drink from regularly. They may need to be reminded -- children have a harder time telling that they're thirsty than adults do. Also, kids should wear loose-fitting clothing when playing outside. That may seem like a no-brainer, but if your child is headed off to sports camp, it's important to inquire what gear they'll be required to wear on hot days.
While physical exertion is one of the main risks for heatstroke, be aware that a child doesn't even have to be moving to experience the heat's effects. That's why it's important never to leave a child in a parked car during the summer; even with the window open, heatstroke can strike within minutes.