Hands usually have a problem when working in sustained cold and wet conditions. Mine surely do. I say “working”: it should be fine if you can keep the expected activity level with hands in pockets but this is often not the case. “Working” usually means hands will be outside, doing things, being exposed to the elements and creating pressure points on the fabric in any protection we might use as a consequence of being holding onto things.
Why hands get cold
To avoid hands getting cold, it is important to know why this happens so we can address the cause, not just the consequence.
The human body is at a constant 36+ degrees. It can’t be at any other, not at least its vital organs. To meet this requisite in an environment where the ambient temperature may be much lower, the body has its strategies. Cold hands is one of them.
When conditions (cold, damp, windy, low energy levels…) threaten our core temperature, the body answers in several ways, two of them very relevant in this instance:
- Avoid losing body heat
- Sacrifice non-vital parts
Our blood is like the hot water in a heating pipe system, delivering heat all over the place. When blood is close to the surface, it is more prone to losing heat to the environment. When the body is aware that saving energy is important, it limits blood flow to the outermost pipes. The areas deprived from blood flow get no heating: they get cold.
Hands are usual suspects. They get all the relevant conditions:
- Non-central location
- High surface/size ratio
- Exposed location
- Technically, they’re dispensable
Put it another way, keeping the hands warm takes a lot of energy, relatively speaking. When energy must be saved, extremities like the hands are among the first victims.
This is why the most intuitive methods of hand re-warming like aggressive rubbing or warm breath exhaling have little effect in the long term. They may provide immediate, temporary relief but they won’t make blood flow return. At the far end of the text I’ll comment on a much more effective strategy for re-warming hands.
Hands are not only extremities, the have unique capacities that no other part of the body can replace so they’re usually out there, doing things. It’d be great if we could keep them under cover every time conditions are tough but this is usually not the case.
Most obvious one is ambient temperature, when it is low enough. It is not the only one though. Let’s check the rest:
Humidity: water is a much better conductor than air. Cold water (cold like in relative to body core temp) is a heat sink: when relatively cold water gets in contact with the skin, there’s heat transfer from the latter due to conduction. Skin gets colder. The higher the temperature delta, the faster this process goes.
Do note the difference between water and air. Air is a much worse conductor. Our skin will be pretty much comfortable in a 20ºC air environment but 20ºC water will feel cold.
On top of that, water will evaporate when heated. This is an endothermic reaction fostered by our own body heat. This is actually how our body cooling system works and it’s so useful for us when we overheat but it may also become a problem when we need to save energy.
Wind: moving air implies heat loss by convection. I can’t fully understand the physics behind how convection affects the apparent temperature as well as any actual heat loss and I will not try to explain it by copying from Wikipedia. It is a known fact that wind means cooling. This may be a blessing or a curse. We’ll check the curse option.
The problem scenario
Low temperature and persistent, heavy-ish rain in a situation where we must keep using the hands. For long hours and with no alternatives. Wind would be an added problem factor.
In such a scenario, it is difficult to keep hands comfortable. I find difficult even to keep them functional.
This is more likely to happen in long distance, self-supported activities. At least it is then that the issue takes more relevance. What works for a few hours may not work anywhere beyond.
It is not deep cold what’s the issue. Deep cold has its own set of challenges but it’s not part of the problem described: when water freezes, ambient humidity is much lower and it can be more easily avoided within the clothing system, hands included. Even if there is precipitation. It’s above freezing what I mean to talk about. It’s hypothermia weather.
To keep hands functional and relatively comfortable for as long as needed.
The idea of “comfort” here does not exclude the hands being somewhat cold but they shouldn’t be painful or anyway bothering. The no time limit means the solution must work indefinitely in a self-supported way. Putting up with it until day’s end at the trailhead is not the question, neither it is altering plans because of the conditions. I need to be self-sufficient as far as this relative comfort goes.
Gloves or mittens
As far as the stated issue goes, it doesn’t matter. Gloves provide better dexterity, mittens are more thermally efficient as well as easier to bulletproof. Still it doesn’t matter much because the problem scenario applies to both. Both eventually fail.
Water is a lost battle
Water will find its way. It’s a matter of time. As far as the hands go, wearing waterproof layers has a limited effect.
No matter what you wear, everything will get wet. It’s important to be aware of this and take it into account for the protective strategy.
The big mistake
Using waterproof/breathable fabrics for hand protection. For two basic reasons:
- It is not necessary
- It soon fails
Waterproof and breathable is quite an oxymoron in real use. This is particularly true for hand wearing: when it’s cold out, hands generate little heat to help drive humidity out; hands are very exposed so any shell will quickly saturate from the outside. And the shell fabric must work under stress and pressure as a consequence of the hands being holding things: too hard for any membrane system that’s not brand new. It will leak.
If the strategy includes a waterproof shell fabric, at least, make it truly waterproof for the expected conditions. This will mean it being not breathable at all but…
Breathability is not really necessary: hands will not perspire much if they’re on the cold side.
Using waterproof/breathable fabrics for hand protection is a commercial strategy paired with a certain lack of interest in the end functionality. Manufacturers don’t expect to sell many items if they’re sold as non-breathable and they’re probably right. This does not make the products that they do sell any better.
Strategies that don’t work
Think of the goal stated above when evaluating whether something works or not. I’ve tried many ideas over the years, some more out-of-the-box than others. The following ones had limited success, at best:
Waterproof/Breathable shelled gloves/mittens
Nothing to do with these, not as stand alone items (shell and insulation) neither in the layering (only shell) approach. They eventually fail and the performance I find rather poor for the reasons explained above. The fact of being aware of not needing the breathability doesn’t help.
Waterproof, non-breathable shells
I’m not aware of any commercially available item like this. I made the ones I have tried out of some silnylon. The idea’s got potential but silnylon was probably not the best choice because of the limited waterproofness, enough for its use as a shelter but not for shell mittens. The rough make probably didn’t help. Anyway, this was hoping to keep water out, which is an idea I have given up with.
Simple, thin plastic gloves
Like those to pick up the fruit at the supermarket stalls or to keep your hands from smelling like petrol for days after refuelling at the relevant station. They’re so light that they had to be tried at least. They can be used as a shell (on their own or as outer layer) or as a vapor barrier (inner layer). The most intuitive use as a shell turns out worse than silnylon as the thin plastic is too fragile. They’ve got more potential as a vapor barrier: at least, this is a step ahead in accepting defeat and trying to keep hands comfortable instead of dry. Then, the outer layer will become a wet mess. It will not provide much insulation.
Dish washing gloves
Same as above, these may work as stand-alone shells or vapor barrier under some insulation (that will get wet) but they’re more durable than the thin plastic ones. They’ve got some potential if temperatures are not too low. On the minus side, they’re tight and become a real pain to put on or take off, more so after everything has got wet.
Of particular interest are the directional systems that render such good results for the torso garments. These are technically waterproof without any truly waterproof barrier. They make use of body heat to pump humidity out through a fuzzy liner whose inner will always keep dry. The real softshell.
It doesn’t work well for the hands. Hands are rather cold and they’re not pumping much. Eventually (rather soon), water soaks in and everything becomes a heavy, wet mess.
If anything, the shell will still keep wind out and the fuzzy liner will still keep some insulative capacity.
Lots of gloves
If you don’t know which knot to use, tie lots of them… the same can be applied here: take more than one pair and change on the go. Try to get the wet ones as dry as possible while you wet the second pair. It’s better than nothing but has limited time expectations and carried weight goes up.
The perfect strategy
I don’t know of any. I won’t be the one to say one does not exist.
Be water, my friend
Sorry for the stale quote but fact is it illustrates very well the best success story with the addition that this is mostly about water anyway: do not fight water, just work with it.
The best implementation of this strategy that I’ve found uses neoprene.
This is what they use when they know they’ll get wet but still need to keep warm-ish. It’s got potential for the case study.
The physics behind how neoprene works are not clear to me… it’s waterproof but it soaks in water. It’s not breathable but since humidity will be all over the place anyway, it seems it doesn’t matter. Does it hold water in small cells, pretty much like air-based insulators? I really don’t know…
Neoprene is not a great insulator when compared to the ones we usually use: down, fleece et al. In the case study, however, the problem is not so much the cold but the combination of cold and damp. Neoprene will not keep you too warm but acceptably cold-ish and, what’s important, it doesn’t matter how wet it gets. It will keep you just as acceptably cold and it will do it indefinitely. It will do this to your hands.
Neoprene is elastic and wears tight. I don’t know if this is a requisite for its working the way it does or a side effect of its own structure. If it needs to be tight against the skin, only gloves would work, neoprene mittens would be out. I’ve never seen neoprene mittens anyway but I have seen and used neoprene gloves with a fuzzy liner that were not particularly tight and they worked quite well.
Neoprene gloves can usually be found in 2 and 3 mm. thicknesses. I’ve never seen them in backpacking oriented stores. They can be found in the diving or cycling sections.
Neoprene is relatively heavy, certainly more than fleece or high-loft insulators.
Being elastic and tight, it is difficult to put on and take off, particularly when everything has got wet. 2 mm neoprene allows pretty good dexterity but there’ll come the time when you need to take gloves off. You’ll hate them then.
Neoprene alone is not a great insulator. Be ready to be in the cold side of comfortable.
Neoprene gloves are difficult to fit in a layering scheme. They perform best when planned to be used on their own.
Application to long distance backpacking
Neoprene has the best potential I’ve found to meet the stated goal: keeping hands working and relatively comfortable in long-lasting hypothermia weather. However, it is not a good insulator and it layers rather poorly. It is a path worth exploring if only for the cold/wet performance but it would need to be the only hand wear you need. Neoprene gloves are heavy enough on their own to need another layer. Both would be mutually exclusive.
2 mm neoprene is reasonably light and works well enough. It’s my current choice for 3 season conditions.
3 mm neoprene with a fuzzy liner is too heavy but it might have a place in 3+ conditions or for cycling, where hands are particularly exposed. That’s probably why I found these in the cycling section.
When everything else fails
Sometimes hands get painfully cold, even to the point that they start to lose functionality. It certainly happens to me. Rubbing or breathing into them is relieving but does not solve the problem. There is however a simple exercise that does. A real turning point for me, it really improved the quality of my experience in the outdoors.
Remember the comment above about our blood working as a pipe heating system? And how hands get cold because of blood flow restriction… so in order to re-warm the hands, you just need to re-establish blood flow. You can use centrifugal force.
If you follow soccer, you’ll have surely noticed goalkeepers spinning their arms in cold days, particularly when the the opposing team is not challenging and the keeper remains inactive. They need hands in good working order.
We can do the same: keep arms straight and swing vigorously, up and down, making an arc in front of you, like if you’d be trying to send your hands flying out as far as possible.
Your hands will hopefully stay put but your blood will flow outwards. This is so powerful that you can actually feel it happening, as if your capillary were about to blow up. It’s even painful for a short while if the flow was heavily restricted.
This goes against the body’s strategy described above to prevent heat loss but body responses are sometimes rather bold. Your body does not need to know that you are well fed and you’ll keep your energy levels fine so you’re allowed to cheat. Don’t do this however if you’re hypothermic or at risk of being so.