That's very interesting Midnight. I've known for some time, from other research your post last year, that hypothermia comes sooner if you are already calorie depleted, but I think what you are saying here is that it not only comes sooner because you have less energy to stop the heat loss, but even sooner than that because the core temperature and brain temperature doesn't have to drop as far to start malfunctioning. So we should constantly asks ourselves not only is our core temperature warm enough, but also do we have enough glycogen stores and hydration level, since bonking and dehydration and hypothermia are all so closely related.

I think the other thing to keep in mind it how much of a reserve we have for what ever situation might hit us, like falling through ice, or being exposed to cold wind after hiking up a long hill, or just gradually getting cold and tired and stupid. Our short-term reserve, like within the hour, is probably a function of stuff like our glycogen levels in our muscles and liver, but also such things as how much reserve heat is stored in our outer layer of skin and our clothing, and how much moisture our clothing can absorb before it becomes saturated. Those three things are our short term heat tank. We can speed up our activity to reduce our heat loss, but ultimately its all coming out of the same tank. Sometimes you need to stop and eat and dry clothes and warm up in a sleeping bag, especially if your in really bad shape and conditions are deterirating. Other times it might be sufficient to slow down to a slow but steady trudge with enough extra layers that you are warming up but not sweating. When in doubt, especially after you discover a lapse of judgement or clear thinking or balance, its probably best to stop and eat and get warm and rest up and reassess the situation before continuing. Sometimes you have to walk a little ways to find a place to take a break, but putting on extra layers and trudging there is probably better than going in a hurry. That allows you to burn more fat and save your carbs, and even make a few carbs from muscle. If you fall through the ice or something like that it can be a little different, as you can get into a race against time. I guess in Iceland if your rowboat flips over the rule is to swim for shore as fast as you can, rather than to stay with the boat. Different strokes for different folks. I think the idea is to try and stay topped up, especially as conditions deteriorate, and always try to avoid situations that would require more effort than a stop for the night or a slow steady trudge to get yourself out of trouble when things go badly.

Just my thoughts.