artrock23 wrote:Really? Explain, please.
The high, cold mountain environment is very dry. The work is hard. Lots of heavy breathing. Tremendous amounts of moisture are lost to the atmosphere from the lungs. It's a real pain-in-the-ass to melt snow for water. No one drinks enough. Everyone walks around dehydrated.
Dehydration means that the periphery of the body is poorly perfused with blood, relatively speaking. Fingers and toes get cold.
Staying well hydrated means that your extremities will be better perfused - and assuming that you keep your core and extremities insulated - a perfused extremity is a warmer extremity.
If your core gets cold then your body will shunt blood away from your extremities - and your fingers and toes will get cold. So you've got to keep the core warm, too.
Failure to insulate your extremities will also permit your body heat to be radiated to the environment - so you've got to keep that warm extremity insulated.
It's all very dynamic and there are multiple co-dependent factors. But overall, proper hydration is really key to staying warm. A thermos filled with hot water is worth it's weight in gold.
I just did a quick Google search on the role of dehydration in hypothermia:http://www.altitude.org/hypothermia.phphttp://www.momsteam.com/frostbite/cold-weather-sports-recognizing-preventing-dehydration-hypothermia-frostbitehttp://www.justanswer.com/medical/67hmf-does-dehydration-cause-hypothermia.html