I recently read this article, and I thought it would be an interesting "talking point" for a CC thread. Even apart from Freeze Fest (a bad idea, IMO, that has only gotten worser!), I recall a thread discussing staying warm in wet/cold canyons. Specifically (IIRC), Tom had suggested that one could take a medication (was it niacin?), which caused dilation of the blood vessels. Whatever the case (and I prefer to stay in the agnostic camp for the meantime), at least there is a clearly proposed physiological mechanism in this case. Scott Carney has written a book, entitled What Doesn't Kill Us: How Freezing Water, Extreme Altitude and Environmental Conditioning Will Renew Our Lost Evolutiuonary Strength: https://www.amazon.com/What-Doesnt-Kill-Environmental-Conditioning/dp/1623366909/ref=sr_1_1?s=books&ie=UTF8&qid=1482539883&sr=1-1&keywords=scott carney which will be released on 1/3/2017. In the meantime, we can discuss his article, published in Men's Journal, linked here: http://www.mensjournal.com/health-f...xtreme-altitude-can-do-for-our-health-w455186 Basically, by following a certain training program/exercise regime, one can gain mastery of their autonomic nervous system (which controls homeostatis), and rachet up their cold tolerance to an amazing degree. Surely this would be incredibly advantageous in canyoneering, and all outdoor activities where hypothermia is an ever present risk. My initial impression is that this claim is a spectacular (though common) case of pseudo-science, which all kind of possible (but irrelevant) "facts" are cited which, upon closer scrutiny, turn out to be entirely improbable and divorced from real-world experience. I am not claiming, necessarily, than Wim Hoff, the Dutch adventurer who runs the training camp in Poland, is a total charlatan. He may indeed have an extraordinarily high cold tolerance. But to bottle this claim, wrap it in pseudo-scientific lingo, and sell it to the public ("any one can do it"), reminds me of the snake oil peddled by charlatans in the wild West, who inevitably left town "before the chickens come home to roost". At any rate, let's thrash it around if you think it is plausible. I value your opinions much more than the headline grabbing stories featured in Men's Journal or Outside.