The name is Lyte. Pedialyte [Update: As Rahul points out in the comment, I took some liberty with "baby formula"; the "baby elixir" that athletes have fallen in love with is actually a rehydration liquid for kids experiencing diarrhea.]:
Athletes are always looking for an edge, even the macho ones who would rather be seen off the field with a Cadillac Escalade than with a teddy bear. But despite that cuddly label, Pedialyte continues to pop up in locker rooms.
If there’s some secret formula to victory, and, these days, if it’s legal, athletes will try it. [...]
From the beverage cart on the Anaheim Ducks’ team flights during the 2007 Stanley Cup playoffs to the training camps of the National Football League teams whose regular season started this weekend, Pedialyte has found its place in the kit bag of professional athletes.