[big valsalva]

Well, yes. Of course your body warms the cold water up to the core temperature. It doesn't NEED to, but it happens anyway. And of course, it does require a certain amount of energy to do so. I see nothing Bro Science about that claim. The figures may be a bit off though. The talk of drinking cold beer, Kool-Aid, Mountain Dew, etc. and accomplishing the same results is flawed in that those beverages contain calories, and the calories your body needs to bring those beverages up to body temperature is more than offset by the caloric content of the beverage itself. Iced black tea and iced black coffee (especially when used to wash down an asprin and ephedra tablet) would accomplish the same result as chilled water. I wouldn't want to rely on the ice water technique as my sole method of burning up excess calories, but to help bust through a plateau, or in conjunction with a serious diet and exercise regimine, it couldn't hurt at all.