 The purpose of this study is to compare two novel active rewarming techniques in mildly hypothermic people. Volunteers will undergo 3 cooling trials in a circulating bath at 14 degrees celsius and will then be rewarmed with either shivering alone, warmed iv fluids IVF, or water perfusion pads applied to the hands and feet. The investigators hypothesize that both heated IVF and water perfusion pads to the arteriovenous anastomoses AVAs will prove to provide significantly superior rewarming rates than shivering alone. 