JACKSONVILLE, Fla. -

Not everyone is excited about being back to school, but there is a lot of excitement with the start of school sports.  And here, the summer heat sticks around well into the season.  So, it's important that coaches and parents understand how to prevent heat illness.

Cleveland Clinic Children's Pediatrician Dr. Richard So says during any stretch of hot weather, the kids must be hydrated.  But he adds, that process needs to start well before the athletes ever take the field.

"Drink a bottle of water before they go to bed and then before they go to practice you drink another one in the morning because when you start your practice at the top of the day you want to start with a full tank," he said.

The American Academy of Pediatrics recommends heat-illness training for coaches, trainers, and other adults. AAP researchers say it's also important to educate the athletes about preparing for the heat and for adults to allow enough time for them to hydrate before, during, and after practices and games.

So says one easy way an athlete can gauge their hydration is by the color of their urine.

"If you are fully hydrated your urine should be almost clear. If you're peeing out, the darker it is the more you're behind on your fluids," he explained.

A 2011 study by the Centers for Disease Control found that football causes the most heat illnesses among young athletes. That same study found that baseball and softball causes the most heat illness in girls 14 and under.

So says coaches and parents can look for one particular sign that the heat may be getting to their players.

"In a lot of the articles that I've read, in regards to the one tell-tale sign of these catastrophic events, the one thing that happened to a lot of the kids is that they vomited," So said.

AAP researchers also recommend coaches schedule at least 2 hours between same-day contests in hot weather and that they have an action plan in place to treat heat illness.