The name describes the process, for example, deionized drinking water. Either carbon dioxide is added, or water is naturally carbonated. If carbon dioxide is added, it can't be any more than its naturally carbonated level would be. It can only be labeled as natural sparkling water if there's no added carbonation. Seltzer and club soda are considered soft drinks, not sparkling water.
Spring water comes from a natural spring in the ground.
It may or may not be carbonated. As a result, they're at greater risk for dehydration. They generate more body heat with exercise, too. Children don't adjust as quickly when they exercise in hot weather. Protective gear used in many sports, such as hockey and football, hinders their bodies' ability to cool off, too.