Hydration - General

Sweating results in the loss of both electrolytes (particularly sodium) and water. Orange juice, moderate salting of food in the diet, and sports drinks help replace electrolytes such as sodium, potassium, and chloride lost during sports. 

Surprising, as it may seem, the most important part of an athlete's diet isn't what they eat, it is what and how much they drink. Drinking fluids before, during and after sports is especially important for pre-adolescent children because they have special fluid needs compared to adults, or even teenagers. Recent research, however, suggests that a "one-size-fits-all" prescriptive advice to drinking is outdated because sweat water losses are dynamic and and because the three main drivers of sweat water loss are highly variable in children.