Not to get too off topic but quick Google yielded this first hit.DennyDoyle said:
F*ck. That keeps happening to me. I think he's probably forgotten more about high performance athletics than I've known, so I was genuinely curious. But back to your regular programming . . . .
http://breakingmuscle.com/nutrition/cold-vs-room-temperature-water-during-workouts
Power lifters could bench press more drinking room temp water vs. cold but no effect was found in other athletes. Seems right to me - that it would only have a significant effect in a situation where you are pushing your muscles to failure. All those calories matter in an extreme situation like that. It's far from what is happening in football. Otherwise, they'd have to take the starters off the field every game.