Ken Bob Saxton, in his book Barefoot Running, Step by Step, identifies what he calls B.R.E.S.: Barefoot Running Exuberance Syndrome. He refers to some of the pains one can get when getting too exuberant about barefoot running and overdoing it. Like everything else, you have to work up to barefoot running.
The same principle applies to acclimating to the cold. I’ve called that Acclimatization Inadequacy Syndrome.
Unfortunately, sometimes those of us who push the limits of barefooting can overplay its ease and comfort. We’ll regularly go out in near-freezing temperatures (and enjoying the heck out of it) and do just fine. Then the newcomers to barefooting try it, get uncomfortably cold, and wonder what they are doing wrong.
The answer is they are not doing anything wrong. It just takes longer than you think before your body (and your feet) adjust to cooler temperatures.
Let me give some observations on what works and what doesn’t.
The main thing new barefooters need to know is that it can take something like 3-6 years (yes, that’s years) for the body to adjust to cool-weather barefooting. At first one can wonder a lot just how others do it, but it really takes that long for changes to occur. Each winter your feet will be a bit better at dealing with the cold, but it is unrealistic to expect full acclimatization more quickly.
I imagine that could get acclimated sooner if there weren’t that annoying, intervening summer
.
Here are also some tips.
You’ll do better if you are moving around, that is, running or hiking. Don’t just sit there in the cold. (When my kids were in high school, I’d go to football games. Just sitting there could get uncomfortable.) If you are moving around, that is helping to pump warm blood down to your feet and getting they used to operating in cooler temperatures.
I’ve mentioned before that leg warmers can also be used to help keep you warmer. As the blood passes through your ankles, it is much closer to the surface of the body than in many other locations, so that can deliver pre-cooled blood to the feet and inhibit comfort.
Actually, one of the best things one can do to get your bare feet used to the cold is snow-shoveling. (No heart attacks, please!) One reason is that you are generating a lot of heat. There is no question that your body core temperature is being preserved, so the flow of warm blood to your extremities will be maintained.
You can also do the shoveling just the way you do reps when exercising. Do a bit, pushing yourself slightly, then go back inside for a while. Repeat. Not only will this give your feet the stimulation they need to acclimate, but it will also teach you just how various levels of cold discomfort feel so that you know when to quit.
However, just as it is with lifting weights, don’t overdo it. You’re not trying to damage yourself, just prompt your body to make changes will within its normal capabilities.
One thing that gets me every time is getting snow on top of my feet. My (thicker) soles provide a fair bit of insulation that slows heat loss there. That’s not true of the tops, and getting snow there will cool your feet very, very quickly. If you have to tromp through deep snow, my suggestion is to put on shoes! Or do as Cody Lundin does: wear a couple of layers of wool socks.
Speaking of Cody, in the first Dual Survival episode he talks a bit about cold training. Here’s the video:
Here’s what the narrator says:
Native arctic cultures have adapted to the cold on a cellular level over generations. Cody is trying to do it in just one.
Here’s Cody’s explanation:
I’ve been going barefoot for over 20 years. It trains the mitochondria, which are small organelles within the human cell. They’re the body’s furnace. It makes them train harder and longer, which helps me produce more body heat on a day like today.
And Dave’s not buying it:
If he chooses not to wear shoes, and not to wear pants, it’s bush-hippie logic and Mother Nature stuff that I don’t get.
I was rather suspicious. You’re not going to evolve cold-resistance in a single generation.
Well, I forgot about the way that existing genes can be upregulated.
The genes are already there. But the cold really can train cells to modify their internal genetic structure. There actually are changes in the brown adipose tissue (brown fat) gene expression that conveyed greater heat generation from those cells. For instance, as it says in Biogenesis of thermogenic mitochondria in brown adipose tissue of Djungarian hamsters during cold adaptation, Biochemical Journal (1996) 316, 607-613, by Klingenspor, et al.:
[T]he maximal rate of protein synthesis analysed in a faithful in organello system was increased 2.5-fold in mitochondria isolated from BAT after 7 days of cold exposure. We conclude from these data that the biogenesis of thermogenic mitochondria in BAT following cold adaptation is achieved by increasing the overall capacity for synthesis of mitochondrial proteins in both compartments, by increasing their mRNAs as well as the ribosomes needed for their translation.
[OK, this study was done in hamsters. But there is no reason to think it doesn't also apply in humans.]
Another interesting study to read is
Adipose tissues from various anatomical sites are characterized by different patterns of gene expression and regulation, Biochemical Journal (1993), 292, 873-876, by Cousin, et al..
So you really can train yourself to adapt better to the cold.
Of course you don’t really need to know all the scientific information to do so. Just go out and push your limits a bit.
And realize that the full changes you are hoping for will not happen overnight (or even particularly overmonth). Patience, grasshopper. It will eventually come.

Interesting, I actually saw this episode the other day, funny that you brought it up. Cody is a beast, that is all I can say!
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