I heard somewhere that the best way to keep warm in a sleeping bag is to strip off to your underwear, with the logic that layers of clothing will not allow the bag to reach it full potential, due to air being trapped between you and your clothing.

Now I tried this in an Artic simulator (Great Britan woods) recently. I took my pants off and left a wollen jumper on top.

My legs froze and the top half was ok.

Now I get to thinking. If my clothing is working as insulation, not letting my body heat escape out to the bag, then I should still be warm, once the clothing I am wearing isn't keeping heat in, then I might get cold, right?

How do you folks go about it?

Express,
I always wear at least something when in the bag.The main idea being to keep the bag a tad cleaner,sweat and all.
2:The only heat when in the bag is produced by your innards.
How you insulate that to the outside is irrelevant.The bag does not provide any heat.The result:The more you wear inside the bag,the warmer you shall remain

sheephunter

Hi Express,

I think the Army recomends stripping down to your under shorts but I can't get it through my head how that could be warmer!!! I leave my long underwear on and I always make out just fine. The only problem that I can see with this is if you sweated and got your bag damp. I usually unzip my bag a ways so that if I get too warm I can let some cooler air in.

Hawkeye47

Ah ha, the army bit rings a bell, I might recall that this piece of advice was given to me by a Marine...

I have always slept with long underwear on, I just thought I'd try this version. one things that does work to warm yourself and the air within your sleping bag is to do a few pushups (if you're alone ;-) ) when you get in.

I have heard of sleeping naked, what I was told was the bag will absorb persperation. I've done a fair amount of cold weather hunting, I think sleeping naked is BS, I like to sleep in long underware. There's a time to sleep naked and theres a time not to.

From what I recall the reason for removing clothing in the sleeping bag was to retain those garments thermal efficiency in the morning after getting out of the sleeping bag. Or something like that.
Bill

If it is really cold then I will line my sleeping bag with a thin blanket anyway.

I generally sleep in my underwear unless it is very cold then I will sleep in long underwear.

I also leave all my clothes in the bag with me so they will be dry and warm in the morning.

After many nights in a sleeping bag from hunting Alaska to climbing mountains in below zero up to summer temps, the more you wear into the bag the warmer it will keep you. When you hunt or climb you will also be proud of what you already have on your body at wake-up time the nest morning, or in the middle of the night as in Climbing high. You can increase the temp rating of the bag by wearing cloths into it, (should I have said lower it) or throwing a blanket or tarp over the bag. This hunter is gratefull for the backpacking and climbing experiences that taught me about the cold. Good shooting.

Hello;
My own experience says avoid breathing into the bag in cold weather, as in pulling it over your head. The moisture in your breath will make you cold and clammy. I usually strip down to a T shirt and shorts. The bag after all is supposed to keep me warm and again it avoids moisture building up in my clothes.

Grizz

Hello again;
One thing I forgot to mention is the importance of airing the bag out, daily if possible, again to get rid of the accumulated moisture.
Grizz

EXPRESS,

I've actually done quite a bit of camping in minus 20-30 weather. What I found is that changing to a fresh set of long johns just as I went to bed, wearing a stocking cap and having a minus 40 bag made sleeping fairly comfortable. As others have mentioned moisture is your enemy. Do not wear so many clothes in your bag that you perspire. Your clothing will get damp and your bag will loose its loft/insulating value and you will be cold and miserable.

Regards,

Mark

Mate



- when I mentioned that it was amazing how you warm up when nekkid in a sleeping bag - maybe I should have clarified!! That happens when you are sharing it with a nice warm female - or, in your case, a nice warm pig!



Her Majesties armed forces all sleep in long underwear Mate - some of it their own!



Have a good one Bud - you will acclimatize eventually!



Ian

I wear a different set of long underwear in my sleeping bags than I wear during the day, I prefer silk undies for this as they are super-light, compressible and easily laundered in tent camps as they dry rapidly.

I do not sleep in my clothing, althhough I have as the bit of extra warmth is offset by the accumulation of sweat and by the dirt that can be brought into the bag from hunting clothes.

I do not put tarps, etc. over my bags as this can compress the insulation and increase vapour retention causing a reduction in effectiveness. A tarp suspended above the bag can aid in longwave radiation heat retention and moisture control, so, that is what I do.

A Gore-Tex and down bag by a top maker, such as Integral Designs, Feathered Friends or Western Mountaineering, under a very light tarp and worn with the light longjohns gives me the best sleep of anything I have tried, I have used this to sleep in recorded temps. of -40F in relative comfort.

In typical hunting season crappy weather, I have and do use a synthetic bag as an emergency bag, I will be shortly getting a "Wiggy's" for this purpose, the design is the new style developed on the Kifaru board.

The Canadian Armed Forces recommend sleeping naked when in Artic conditions. This is for extremely cold temps. This also assumes one thing and that is a bag of sufficient insulation. Not one of your -40 Cabelas bags, but a real one. The theory is, as has been mentioned, the moisture. Damp clothes negate the insulation and getting out of a bag with damp clothes can be a killer. Putting clothes in your bag is a no no as the moisture from your body will make them damp and when you put them on it will freeze.

They recommend turning the bag inside out and allowing any moisture to freeze on the bag and give it a snap to seperate the frozen moisture from the bag. They are talking real cold here.

Like Kutenay, I have slept in 40 below before also, more than I care to remember.

First you loose the most warmth thru the top of your head, so I sleep with a wool hat of some sort covering that. A good down bag is the best thing to have.

My bag has good enough insulation that I do sleep with a tshirt and a good fleece blanket in the sleeping bag with me.
I also sleep with a pillow to hold in the body heat like I am holding my honey.

If I can have it, I have along another regular low cost sleeping bag that I toss over my down bag, like a blanket.

And I wear socks to keep my feet warm. I have slept that way in 40 below and have been perfectly warm.

You want to hold in body heat, you have the air around you be able to breathe, if you don't, your body will sweat and the sweat will freeze,

also make sure the area is well ventilated. if you sleep in a truck like I have, I actually will leave the windows cracked so my breathe will not humidify the area i am sleeping in and freeze and then have your lungs breathing cold dam air. You will get a nice cold with that.

Real cold temps are usually very dry, so you will only get moisture from your own warmn breathe and breathing it back in.

I knew a lot of this stuff from Cold Weather Camping, but I also learned alot about it, being in the Army Medical Corp and having to train troops and advise units on field training in Arctic Conditions.

Cheers and Good "staying warm"
seafire

Until you sweat there sheep hunter, and then that sweat will freeze and you will not be so warm any more.

Evidently you haven't experienced it before

seafire

As many have mentioned, it's moisture that is the real enemy!

I usually use a down bag, and I sleep in whatever the conditions dictate. I am a pretty big guy, and I give off alot of heat. Unless it is really cold, I often leave the bag somewhat open to ventilate.

Because of this, I often wear a light sweater or fleece when in bed. Underneath is usually a poly pro shirt.

I wear long poly pro underwear, as I find that my legs get clammy if they are bare, probably because of moisture build up.

I never bring my pants or heavier gear inside the bag, I use them for a pillow. so my head keeps them somewhat pliable

I sometimes wear socks, and sometimes don't.

What I sure as hell DON'T do, is bundle up before I crawl into the bag, as you are going to SWEAT large, and be cold!

My Dad taught me to strip before getting in the bag. Later, I thought "...well that's a crock, I'll need to be able to hope out of this bag right quick so I'll wear my clothing (or at least the long underwear)." Climbed in the bag (with my wool cap) and not 1 hour later was freezing so badly I was shivering in the bag. Stripped in the bag and shoved the undies to the bottom of the bag. Warmed right up and slept the rest of night through.

I have lined the Army issue bag with a poncho liner (an insulated blanket made entirely of synthetic fiber) and slept in colder weather. I've also slept on a doubled over poncho liner on a doubled over poncho under a poncho liner which had another poncho on top. People in bags around me were freezing but I was dressed, warm and even though the snow was piled on top of me in the morning, not at all uncomfortable. Temps were in the mid-teens.

I think how well you've eaten has quite a bit to do with your comfort level as well as does your body fat level.

Hi
Usally wear some long woolunderwear in cold weather. Helps a lot when you are supposed to get out of warms bag in a cold morning. Just remember to get something under the bag. A rein deer skin is perfect. Almost everything exept one of the inflatable things is okay.

Johan

I usally just wear my underwear and I find I sleep warmer it is do to the warm air in the bag. In a larger bag you probably would sleep colder. I put my long underware on the outside of the bag. Or under it for insulation. A good
example of this is too many socks and cold feet no air circulation.

Sleep naked and bring an attractive opposite-sex sleeping bag partner. If it gets cold, "move around" unitl you warm up, you'll also sleep better afterwards.

Express, a trick I've learned is get yourself one of these "hard" plastic Nalgene quart bottles with the screw on lid. It must be the hard plastic though. Boil some water, put it in the (hard plastic type because the soft plastic type could burst or become soft and actually have the cap loosen up or come off) Nalgene bottle, seal it up good and tight throw it in your sleeping bag and It's good till 4 or 5 in the morning, depending on when you go to bed, giving you a warm and toasty night's sleep. Works for me. My feet get cold easy and I put it down by my feet and it warms up the whole bag nicely. I don't do the naked thing though unless I've got a female partner.
choke