School athletes looking to boost their performance before a big game or rigorous practice may see sports drinks as the solution. But do these beverages really deliver?

Sold at most grocery stores and in school vending machines, sport drinks promise to deliver energy and replenish lost minerals and electrolytes. However, the best beverage to drink before and during a sporting event or practice usually is the simplest: plain water, according to the American Academy of Pediatrics (AAP). Drinking 4 to 8 ounces of water during every 15 to 20 minutes of activity serves most school-age children and adolescents well.

Sports drinks, marketed as performance boosters, generally contain carbohydrates and electrolytes. But the products’ claims are not evaluated by the Food and Drug Administration, according to Michele LaBotz, M.D., FAAP, a sports medicine pediatrician and member of the AAP Council on Sports Medicine and Fitness. She suggests athletes drink water or milk at least an hour or two before a sports activity and eat a salty snack to keep electrolytes up.

Fruit juices and soda are poor choices because they contain too much sugar, according to the AAP. In addition, salt tablets should be avoided because they can cause stomach irritation.

Colorful, flavored sports drinks can serve a purpose for children who need encouragement to drink enough liquids to stay hydrated and avoid the hazards of hyponatremia. This life-threatening exercise-induced salt/water imbalance is rare among young athletes performing for less than four hours, Dr. LaBotz said. For athletes who will be competing or practicing for more than an hour, sports drinks may have the upper hand over water, she said.

To determine how much hydration is needed, the young athlete should be weighed (unclothed) before and after the sports activity, according to the AAP. Body weight should remain about the same. One pound lost equals 16 ounces of liquid lost. Failing to take in enough fluid or calories can cause decreased performance.

Finally, sports drinks are unnecessary after a workout or game. Instead, the AAP recommends eating a carbohydrate-rich snack within 30 minutes of intense exercise followed by more carbohydrates two hours later to aid athletes’ recovery.