+1 on most of the above. Water is not optional - your body and mind does not function properly, and you freeze much faster without fluid. Peeing color is the best indicator...


Poor ydration severly limits your ability to fight off cold. A hot drink is best if you are cold, but a cold drink is infinitely better than no drink. You may want to adjust your drinking cold water into periods with surplus heat (i.e. high activity, or when moving). Eating snow is not recommended - it requires calories to melt, and burning those calories requires more water than you gain. (You CAN eat SOME snow in periods of high activity -- but you will NOT be able to gain much fluid this way. Think of it more as an extra "cooling device").


Oh, and one point about nordic skiing: There is no law that states that nordic skiing needs to be an aerobic activity. I do both a "hiking skiing", which is at a leisurely, low aerobic pace and as a training exercise I ski as fast as I can (high intensity aerobic). Depends on what kind of trip I do, whom I go with and what our purpose is. Also, I ski with heavier gear at my "hiking skiing" trips. Going downhill with telemark turns is just too much fun.... Using skis that are somewhere inbetween "nordic racing skis" and slalom, we call them "mountain skis" as you can use them skiing off tracks in the mountains. I reserve the thin, light ultra-fast-track running "nordic skis" for aerobic training purposes only.