You need fluid after exercising, to replace water lost through prespiration. You need a little sodium, to replace lost salt, and some electrolytes. A little nutrition is good too.
But do you need a specially “manufactured” sports drink? Of course not! Everything you need is found in nature. Just dilute orange or cranberry juice with a lot of water, add a pinch of salt, and you are all set!
The sports drink craze may not be harmful to your health, but it isn’t necessary either.