Most kids don't need to be drinking sports drinks after exercising, and they most certainly do not need caffeine-laced energy drinks, pediatricians advise in a new report.

The American Academy of Pediatrics notes in a report published online Monday that both sports drinks and energy drinks are being marketed to kids and teens, but in most cases kids don't need them.

Not only do the drinks have too many calories, some of the products contain substances that could be harmful to children.

The report authors say that many teens seem to be confused by energy drinks and sports drinks and think of them as essentially the same. Many seem unaware that they don't require either of them.

They say that many kids are drinking energy drinks – and the heavy amount of caffeine they contain – when their goal is simply to rehydrate after exercise.

"This means they are ingesting large amounts of caffeine and other stimulants, which can be dangerous," says Dr. Marcie Beth Schneider, a member of the AAP Committee on Nutrition and co-author of the report.

No child or teen should ever be drinking energy drinks, the authors say, and in general, caffeine-containing beverages should be avoided.

Energy drinks have been linked to a number of hospitalizations, due to heart palpitations and seizures. They've also been linked to strokes and even sudden death.

The American Academy of Pediatrics have raised a number of worries about the drinks, saying that not enough research has been done on their long-term effects in kids -- especially those with medical conditions that may increase the dangers.

While sports drinks have not been linked to hospitalizations, they too contain far too many calories and most kids simply don't need them, the report authors say.

They say sports drinks contain extra calories that children don't need, and could contribute to obesity and tooth decay.

While they contain minerals and electrolytes that can be helpful for young athletes engaged in prolonged, vigorous physical activities, in most cases they are unnecessary.

"For most children engaging in routine physical activity, plain water is best," Dr. Holly J. Benjamin, a co-author of the report, said in a news release.

Ottawa-based physician Dr. Yoni Freedhoff, who was not involved in the report, but who specializes in obesity management, would agree with the report.

"The bottom line is: we really don't need these drinks," he told CTV's Canada AM Monday.

"Kids aren't busting their humps hard core for an hour straight and therefore potentially earning or requiring a sports drink. They're playing in a field, they're relaxing, they're having a good time. Unless you're really burning it for more than an hour straight in very vigorous, intense exercise, all we really need is water."

Dr. Freedhoff noted that the average large bottle of Gatorade has 7.5 teaspoons of sugar. He believes the amount of calories that kids are already getting from many drinks is "ridiculous," and "indeed, childhood obesity rates have tripled in the past 30 years."

He says even children who don't have a problem with their weight should be drinking water for rehydration, not sports drinks or energy drinks.

"Whether your kid is obese or not, over time, if this is the habit that's developed, that skinny kid who likes their liquid calories, may grow," he says.