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trailfinder
12-15-2004, 12:04
Other than layering clothes resulting in more weight and bulk, what are the atlernatives? Expensive thermal underwear, e.g. under armor? Thanks!

SGT Rock
12-15-2004, 12:32
Well layering is a part any system. But there are other tricks.

COLD-

C = clean. Stay as clean as possible and keep your clothing as clean as possible.

O = Overheat. Prevent overheating by dressing in layers. Remove layers when needed.

L = Layers. See above, but also have layers you can add when needed in camp.

D = Dry. Staying dry is 50% or better of the battle.

Also staying out of wind or wearing clothing that can block the wind, carrying a hot water bottle to bed, eating high fat foods before bed, going to bed with an empty bladder, using a pee bottle, etc. All little tricks of the trade.

jackiebolen
12-15-2004, 12:32
The best way to prevent hypothermia is to ALWAYS have something warm and dry to put on when you get to camp and having a dry sleeping bag to crawl into. When you're hiking, it's not so much of an issue what you wear as long as it's not cotton because the hiking will keep you pretty warm.

rocket04
12-15-2004, 12:34
Other than layering clothes resulting in more weight and bulk, what are the atlernatives? Expensive thermal underwear, e.g. under armor? Thanks! If you really want to go as light as possible, the sad answer may be yes. The lightest stuff out there is likely more expensive. Whether you need to have that many layers is another question. If you're doing winter hiking, chances are you'll end up with a little more weight or bulk no matter what. But you can manage in the 20s without needing too many layers or expensive stuff. Just make sure that when you get to camp you have a good sleeping bag to curl into though, it's easy to stay warm while hiking but not so easy when resting. Having said that, the folks with lot of experience in winter hiking will surely have better advice.

SGT Rock
12-15-2004, 12:40
As to bulky clothing issue. My system is this:

Temps above 60:

Wear wicking t-shirt, microfiber underwear, nylon shorts, running socks, and have an extra set of socks and underwear in my pack. I also have a rain suit that has pants, bottoms, Sealskins, and gortex mittens. If the weather spikes down or gets wet, this does the trick.

Between 40-60:
Add an extra pair of socks, long johns, a knitt hat, and some fleece gloves. Very little extra bulk. I have found that the heavy weigh brown polypro underwear the Army issues is just as good and a lot cheaper than some of the high tec high end stuff.

Below 40:

Add a field jacket liner and field pants liners to wear under a rainsuit. Adds better insulation than the same weight of fleece and compresses better. I also add a polypro neck gator to turn my knitt hat into a balaclava, an extra set of warm wool socks, and some fleece mittens to wear under the rain mittens.

It ain't a lot of bulk or weight using a layering system similar to this.

TakeABreak
12-15-2004, 12:52
The above is really good advice, but I would to add a couple of things.

1 Always change your shirt when you get to camp, the one you have on will be damp from wear your pack, and as soon as you stopyou will notice it robbing your back of heat.

2 Put on a fleece or wool sweater to, this will very important to conserve body heat.

3 After I did the above and my bedroll setup in the lean to or tent, and my meal cooking I would change my socks, let the feet breathe a second and pout on dry socks.

4 I carried a wool cap and gloves, did not always wear them, but as soon as I got into camp I would don the on. i also used them to regulate my body temperature, when I would start getting warm I would off the gloves, and warming I would take the cap off from time to time.

5 as said above wear layers when yuoustart to get warm, shed a layer at a time.

6 Dry a dry and warm sleeping bag is very Important, if you are getting chills during the day, call it a day set up camp and get in the bag for a while you will warm and quickly. Its better to do low miles today than none ever more.

rocket04
12-15-2004, 12:59
A wool hat will definitely make a world of difference in keeping you warm. Keeping your head warm will likely have you feeling 100% better in cold weather. It sure saved my ass during some cold nights.

Doctari
12-15-2004, 13:00
First let me say, from experience, Hypothermia SUCKS!!!!

The best thing you can do is to keep your withs about you, dress as warm as you reasonably can (in layers as you mentioned, as much weight as you are willing to carry) BUT, be prepared to stop, set up your shelter, & get warm however you can, usually by getting into your sleeping bag. Be prepared to stop before the Hypothermia gets a hold on you, set up your shelter, & get warm however you can, usually by getting into your sleeping bag.

I "Know better" having fairly extensive medical training, yet I have been caught by the beast TWICE! Embarising (almost as much as my spelling :D ) & fortunatly I survived both, the last one because I happened on some other hikers at the Rich Mt fire tower who saw My condition & helped me set up camp (insisted actually) & got me into my warm sleeping bag. I protested, but was outnumbered, once I was warmed up, I saw what was happening. After cooking dinner, & getting warmer, I realised I may well have died on the AT, I was that bad.

Hypothermia is a decetful beast, first you are cold, but keep hiking, then slowly your thought processes slow down, then you FEEL warm, "OH, I'm OK now" is what I thought at this point both times. All I felt at this point was exceptionally tired. I was almost to the point (about 1 more mile of hiking I think) of laying down in the middle of the trail & going to sleep, possibly forever, yet I wasn't aware of being cold. Both times it was raining, but not very cold, about 50f, I was wearing a rain jacket.

So Trailfinder, thanks for the post! Carry what you want, be alert!! Probably carry/wear: Poly pro long underwear (tops & bottoms) a medium weight jacket (to suit YOUR temp range) a extra pair of socks or 2, the socks can also double as mittens, I like wool, a wool or fleece sweater also doubles as a pillow. Wear a hat! Avoid COTTON! A cotton shirt takes 6 weeks to dry (not really, but it will seem so). Stay dry! This may mean that you should hike cool, to avoid sweating, in order to stay warm when you stop. Be aware that when you stop shivvering (as I had last time) That is a BAD sign, a VERY BAD sign, so stop & get warm NO MATTER WHAT!

Doctari.

Alligator
12-15-2004, 13:23
Thanks for sharing that information Doctari. It really helps to show that hypthermia can strike at temperatures that are not really that cold. Were you an obvious case (to others)--soaking wet? What was it that the other hikers saw that made them insist?

As for me, I have a pair of 200 wt. fleece gloves, fleece neckband, fleece headband, and windstopper hat that I use to maintain body warmth without sweating. These items give me a nice range while hiking to adjust to uphills, downhills, and shadows w/o having to switch into and out of core warmers(shirts, etc) and/or pants.

At most when hiking, I will only have two layers, polypro top and bottom and outer shell. If it's really cold (below 20F), I will add an item to my core.

Footslogger
12-15-2004, 13:35
Couldn't help but post an entry to this thread. Reason being ...that I slipped into hypothermia last year on my thru-hike and it wasn't one of those real obvious situations.

It all began as I and 2 other hikers hitched out of N Woodstock, NH last September. Something I had eaten for breakfast didn't agree with me but I figured by drinking a lot of water I could "hike it off", so to speak. We got a ride out to the trail crossing and began our climb up towards Franconia. Instead of getting better I got more and more nauseus. I told the other two hikers to go ahead and that I was going to take it easy and I'd meet them at the top. The nausea turned into cramps and I finally decided to just sit down and take a little rest. It was early in the morning. The weather was clear and cool but not really bone chilling cold. In response to the nausea and cramps I began to perspire heavily. My clothing became damp from the sweat and the evaporation caused by the wind brought about a rapid decrease in my body temperature. Within 5 minutes or so I got a bit dizzy and lightheaded and decided to just lay down on the ground off to the side of the trail. As a former paramedic ...I knew this wasn't normal and called out for the other 2 hikers. I went into shakes and shallow rapid respiration. Lucky for me, the other two hikers ran back down the hill and, noticing what was happening, took rapid action. They got me out of my wet clothes, dug out my sleeping bag and wrapped me up in it. After about 10 - 15 minutes my core body temperature was back within normal range and I began to feel more like myself. I was eventually able to hike back down the hill on my own power and hitch back into N Woodstock, where I spent the rest of that day just relaxing and counting my lucky stars.

So ...as can be gleaned from the above, hypothermia doesn't necessarily occur in freezing temperatures and amazingly enough there a lot of contributing factors to a hypothermic episode. As it all turns out, when I returned home after summitting Katahdin, I found out that I had hiked the entire trail with fairly bad kidney stones and what happened that morning was a byproduct of an acute kidney stone attack.

Bottom line is that I was lucky. While I'm at it I want to publicly recognize those 2 hikers (FireFeet and ChickFlick) for responding quicky and appropriately to my situation and essentially warding off what could have developed into a life threatening situation. I owe them a lot and will always credit them with having saved my life and my hike.

Two kidney stone operations later and healthy again ...I remember that day like it was yesterday. We talk a lot about hypothermia in the paramedical circles but until you are a victim yourself it is hard to fully grasp how fast it occurs and how helpless the victim is (despite having a medical background) to help themselves once hypothermia sets in.

'Slogger
AT 2003

SGT Rock
12-15-2004, 13:42
My experience with hypothermia and those that get it is that it usually happens above freezing. The standard temperature is in the 40s when it is wet. The victim isn't always wet either. Hypothermia can happen as high as the 50s.

Blue Jay
12-15-2004, 13:58
The worst part of Hypothermia is that one of the first stages is a lessening of the blood supply to the brain. In short, you start to get stupid (OK bring on the stupid jokes). As if that is not bad enough, you have no idea that it is happening. You think you are thinking normally, but you are not. Unless you survive it, like Footslogger, it's hard to imagine. I got off a Harley once, was wet and cold, but felt fine. I said something to a friend. He knew I had not been drinking, but he told me I did not make sense and was slurring my words (again with your jokes). I was in an advanced state of Hypothermia and felt fine. Remember, if you stop shivering but are not in a warm place you are in trouble, you just don't know it yet.

grizzlyadam
12-15-2004, 14:20
hypothermia can be a very scary thing. i delt with a group of hypothermic individuals in the mountains of new mexico once. you can read about it here (http://www.trailjournals.com/grizzlyadam/).

the lesson being that you should always make sure you are prepared for any situation that may arise, even if that means carrying more weight and bulk.

Alligator
12-15-2004, 15:45
My hiking buddy and I watch for the -umbles and a suggestion I have seen is to ask a less than easy math question (or other topic). Just something that takes a little thought to see if the person is all there. I would expect that if you are with someone you know well that you could spot something wrong with them, but I found Doctari's account interesting because the rescuers became aware of his condition without knowing him.

Good point by BJ about the shivering.

orangebug
12-15-2004, 21:44
-umbles

Grumbles - becomes irritable and cranky
Mumbles - doesn't talk much or clearly
Stumbles - falls more frequently
Bumbles - can't manage to solve problems, such as opening a pack and getting into a sleeping bag.

You will notice that these all involve the brain. Hiking alone in the cold puts you at risk of having to figure out you are in trouble with a brain that is impaired from the git-go. Shivers may be the best symptom to let you know you are getting into trouble, but the -umbles frequently hold sway.

minnesotasmith
12-15-2004, 22:50
I have used TU extensively when the air temps were below -5* F. actual and I had to be outside most of the day. However, I have never cared for how it felt against my skin. The silk versions sound like a dream solution comfort-wise. I am concerned with how well they would work, though:

1) How warm are they, especially when damp?

2) How durable? Would I have to replace a pair after a month or two while thru-hiking during winter conditions?

3) How easy would finding replacements be in trail/near-trail towns? If the answer is "not very", and the durability is such that I can expect to have to replace it, then I would suspect that I'd need to buy extras in advance, having them shipped to me by home base, or in a bounce box.

4) How demanding is care for thick silk? Can I just gently handwash it in a sink, or does it take dry cleaning?

Cost is not so much of an issue for me, as my finances WRT funding for hiking gear purchases have recently improved substantially. :sun

Doctari
12-16-2004, 03:43
Thanks for sharing that information Doctari. It really helps to show that hypthermia can strike at temperatures that are not really that cold. Were you an obvious case (to others)--soaking wet? What was it that the other hikers saw that made them insist?


You are Welcome.

I'm not exactly sure what they saw. All I remember is something to the effect of "You don't look so good". I wasn't soaking wet, just damp inside my rain jacket. As I said, I didn't feel cold, at least not until I was warmed up, then I thought "OH! I was cold!". Perhaps I was blue? Or extremly pale? Knowing my mental condition (In hindsight) perhaps I looked dazed? That was over a year ago, and I still feel those people saved my life, wish I knew who they were.

I wrote this to remind all of the hazzards, and to remind ME that I need to be careful.

I see that others have added to these warnings, Read & Heed them. The life you save may be your own, I was lucky. I solo hike, I will continue to solo even knowing the dangers, I hope I learned my lesson.

Doctari.

BTW: I am almost glad footslogger had a similar experience, another medic having a hypothermic encounter makes me feel a little less stoopid :bse

Pencil Pusher
12-16-2004, 05:12
Have you had some rather incredible pain while the blood gets flowing again in your hands as you warm up? What the heck is that, for the doctor types out there? It seems the best remedy is to shake the hands like crazy and get the pain over with much quicker.

orangebug
12-16-2004, 09:32
I think you are talking about frost bite. You could also rewarm them quickly by putting your hands under your armpits or in your pants.

Footslogger
12-16-2004, 11:57
BTW: I am almost glad footslogger had a similar experience, another medic having a hypothermic encounter makes me feel a little less stoopid :bse==========================

Worst part about it Doctari ...is that I knew what was happening but the onset and progression was so rapid I couldn't move fast enough to help myself. I'm sure another part of that was a bit of DENIAL. This COULDN'T be happening to me !!

'Slogger
AT 2003

Nameless
12-16-2004, 16:29
Hello,

Some points to stress about Hypothermia... It happens when you least expect it, so never let down your gaurd thinking it is to warm to get hypothermia. Born and raised in Alaska, the only time i have gotten hypothermia (and not to bad, only to the point that my thinking capacity was lowered and i stopped shivering) was in the Florida Keys. I thought Florida was too warm to get Hypothermia, so i wasnt prepared.

Another point... DO NOT drink alchohal when it is cold out. I have heard of a countless number of deaths from people ridding out, fully prepared for cold weather on their snowmachiens, drinking as they were setting up camp, and dying from hypothermia without using any of their cold weather gear. You do not feel or think of the cold weather the same when drinking. DO NOT do it.

Drink a LOT of water when it is cold, your body can always opperate better when hydrated. And soda does not hydrate you. If you start feeling cold immediately get warm somehow. Drink warm water while walking, layer up more, prevent being wet at all costs, and all that common sense. But, if someone starts showing symptoms of hypothermia, ACT QUICK!

Get the person into a tent (or shelter) stip them naked, get them into a sleeping bag, WITH ANOTHER PERSON who is not hypothermic. You want to warm their inner core, but not too fast, too fast WILL kill them. Give them hot water and liquids to drink, but not too many. Get help.

Carefull planning and you should never have trouble with hypothermia. And for those frostbitten fingers... swirl them around your head in a windmill motion. It will get blood to your fingertips and warm them up. For the feet, just get to a warm place and massage them, you just have to live through the pain, it will end.

Thanks, and i hope this helps someone,
Pink

Doctari
12-16-2004, 16:58
==========================

Worst part about it Doctari ...is that I knew what was happening but the onset and progression was so rapid I couldn't move fast enough to help myself. I'm sure another part of that was a bit of DENIAL. This COULDN'T be happening to me !!

'Slogger
AT 2003

Yes, DENIAL was initally the main problem with me, then of course the stupids set in & I was "Lost".

Please note: Foot slogger fortunatly had someone there to watch over him, I found someone (6 I think) who stepped in to watch over me, BOTH of us have a fair amount of training in this field, and the temp wasn't "That bad" yet perhaps without the help of others, we may both have "passed on".

On the other hand, I had a great day the next day, and for the rest of the trip.

Doctari.

Footslogger
12-16-2004, 17:49
On the other hand, I had a great day the next day, and for the rest of the trip.
Doctari.=======================================
Amazing coincidence Doctari ...after an afternoon of rest and hydration I woke up the next morning and climbed that hill to the Liberty Ridge campsite like I nobody's business. And, although the kidney stones were an issue all the way to Katahdin, I never had another really bad episode or totally bad day.

'Slogger
AT 2003

orangebug
12-16-2004, 20:39
That is kind of the way it is with kidney stones, chokingchild birth and other episodes of potentially catastrophic events. Once the crisis passes, you are generally good to go.

But you often require assistance of other people. This is much more predictable in winter hiking. I've promised myself never to hike alone (as much as I love it) between November 15 and March 1, at least in the Southern Apps. I'm available as a hiking bud!

stickman
12-16-2004, 21:34
I've never had hypothermia but I remember that some Army Rangers died of it a few years ago, while training in Panama in weather that was in the 50's. These were obviously guys in peak physical condition (actually, they were probably run down by that point in the training). They were in swamps / wet conditions.

Not related to hypothermia, but I once had a pair of very wet boots freeze absolutely rock solid overnight while I was nice and toasty in my sleeping bag. There was no way I could thaw them out (that was the days of heavy leather boots) without actually cooking them over a fire, which would have destroyed the boots, so I tried to warm them up with my feet by hiking. It was like hiking with frozen concrete around my feet. Blister City, only I couldn't tell because my feet were in such pain from the cold. Ever since, I carry a garbage bag and if its really cold, the boots go inside my sleeping bag with me.

Stickman

Pencil Pusher
12-17-2004, 01:18
Kidney stones suck:( No wait, kidney stones REALLY suck...

Youngblood
12-17-2004, 08:51
I've never had hypothermia but I remember that some Army Rangers died of it a few years ago, while training in Panama in weather that was in the 50's. These were obviously guys in peak physical condition (actually, they were probably run down by that point in the training). They were in swamps / wet conditions.

Not related to hypothermia, but I once had a pair of very wet boots freeze absolutely rock solid overnight while I was nice and toasty in my sleeping bag. There was no way I could thaw them out (that was the days of heavy leather boots) without actually cooking them over a fire, which would have destroyed the boots, so I tried to warm them up with my feet by hiking. It was like hiking with frozen concrete around my feet. Blister City, only I couldn't tell because my feet were in such pain from the cold. Ever since, I carry a garbage bag and if its really cold, the boots go inside my sleeping bag with me.

Stickman
Stickman,

I've done the same. When it gets to the point that I have to put wet shoes in plastic bag(s) and sleep with them to keep them from freezing, I also keep a snack or two handy to eat during the night to keep me from freezing. It can be like sticking a bag of ice inside your sleeping bag... fun stuff!

Youngblood

Bloodroot
12-17-2004, 09:53
I read some people mentioning to drink warm fluids. Along with this, if at all possible (assuming the person can get it down) the person to try to eat as much simple carbs as possible. Carbs are the fuel that most quickly transforms into heat and energy.

Along with this, has anyone ever experienced any immersion syndrome (esp. Immersion foot). Seems that would be a common injury knowing people hike in wet socks all day.

Tim Rich
12-17-2004, 10:38
Other than layering clothes resulting in more weight and bulk, what are the atlernatives? Expensive thermal underwear, e.g. under armor? Thanks!

You can get good quality underwear at a good price from Sierra Trading Post. I've had great experience buying their blems and seconds - they guarantee it doesn't affect the fit. My comfortrel long sleeve top, thermax t-shirt and capilene bottoms have all lasted for ten to fifteen years of section hikes and a couple of ski trips per year. The comfortrel top dries very quickly - I can leave it on in camp for as little as a half hour and my body heat has it dried. I have a North Face synthetic t-shirt that cost more but is far slower drying.

Personally, I would avoid underarmor because of its price. It's still too popular to be priced right for me. That being said, my three football players at home all have some, but I've also bought them the Starter brand knockoffs from Walmart (sprawl! My name is sprawl!) and they work well for them short of the style points.

Take Care,

Tim

Footslogger
12-17-2004, 11:24
Kidney stones suck:( No wait, kidney stones REALLY suck...========================

That's a BIG 10 / 4 !!

'Slogger
AT 2003

Pencil Pusher
12-17-2004, 14:19
Stickman,

I've done the same. When it gets to the point that I have to put wet shoes in plastic bag(s) and sleep with them to keep them from freezing, I also keep a snack or two handy to eat during the night to keep me from freezing. It can be like sticking a bag of ice inside your sleeping bag... fun stuff!

YoungbloodAn alternative is to use your boots as part of your pillow. Laying them on their sides like to LLs but the second L upside down (the keyboard didn't have one, sorry), allows you to rest your head on the soft uppers. Throw the gaiters on top to serve as a barrier to the snow accumulation on the boots. Putting the goretex under the sleeping bag helps to not have to put on frozen stuff in the morning, plus I have enough crap inside my already clausterphobic sleeping bag as it is, what with the water bottles, munchies, gloves, socks, thermals, etc. Or prolong getting into your frozen boots for as long as possible and then hurriedly hike your ass off to thaw them:D

I agree with the folks that say sleeping naked, or close to it, inside the bag is warmer than sleeping with thermals on but the downside is when the morning comes and you must put all your clothes back on. Maneuvering inside the bag can be rather awkward and so it becomes a speed-fest trying to put everything on again while hoping to maintain some semblence of that oh-so-toasty feeling of the sleeping bag. If you are getting cold inside your bag and you've already stripped naked, drink a half liter of water or so and you might very well warm up. I don't know the why, but someone told me that and once while I was shivering inside my bag and thinking at 1am of bailing on the trip altogether and hiking out under headlamp, I drank a bunch of water and that sure helped me to warm up. On the naked side, another winter outing had me sleeping in damp thermals and I was getting chilly. So much so I decided to get naked and see if that would help and it did.
Of course the warmest winter sleeping is to have two bags that mate together. Speaking of which, if you're a homophobic guy, get rid of any such stupidity if the circumstances get dire enough. Because you're going to spoon and massage the hell out of the dude (or him you) who's about to or already has gone into shock. Then gloss over that part of the story when you get back home.
Sleeping in a snow cave is a rather warm affair. You're out of the wind and the surrounding temp is around 30 degrees. Plus it'll warm up a little, some of the snow will melt and drip on your stuff and you can etch snow animation on the walls to pass away the time. The downside being it's a rather wet undertaking digging one.
If you want to go in style while winter camping in a tent, buy one of those hanging stove contraptions. Fire that puppy up in the morning and let it heat both your water and tent up while you're snuggled warmly inside your bag. For melting snow, the XGK (not a hanging stove) is the best. Your own personal jet engine.
Oh yeah, and having a piss bottle handy is worth it if you'd rather not go through the whole dressing process to drain the vein in the wee hours of the morning. Just tape the hell out of it so there's no mistaking the bottle and be kind enough to empty it after use if sharing. For women, they can use the freshette, a feminine shaped funnel... more like a detachable penis that even allows them to pee standing up while in the elements without having to hang their ass out in the wind. Speaking of which, there's the rainbow zips on some pants that allows you to drop a load while minimizing the exposure. This can sure come in handy, especially if you're wearing a harness. Just be sure it's zipped up before you glissade...

Blue Jay
12-17-2004, 15:12
If you want to go in style while winter camping in a tent, buy one of those hanging stove contraptions. Fire that puppy up in the morning and let it heat both your water and tent up while you're snuggled warmly inside your bag. For melting snow, the XGK (not a hanging stove) is the best. Your own personal jet engine.

If you want to die in style, running through the snow, on fire, covered in burning plastic. Your own personal jet engine, you got that right.

stickman
12-17-2004, 20:12
Hey, it is amazing how much heat you get in a tent off a single candle! I have done that - very carefully - in a candle lantern. It was downright warm in that tent.

Footslogger
12-17-2004, 20:37
Hey, it is amazing how much heat you get in a tent off a single candle! I have done that - very carefully - in a candle lantern. It was downright warm in that tent.=======================
So very true. Used to do that years ago with my old nylon-tafetta tents. Used the candle lantern with the top plate over the flame. Hung the candle from a line just far enough from the apex of the tent so that it didn't overheat the fabric. Heat from the candle would radiate upward and then down the sides of the tent.

Haven't tried that in years and will never have one in my silnylon tent ...but it did take the edge off a cold winter night in the mountains while I sat up reading or journalling.

'Slogger
AT 2003

Pencil Pusher
12-19-2004, 00:42
If you want to die in style, running through the snow, on fire, covered in burning plastic. Your own personal jet engine, you got that right.
I probably should've separated those two ideas. When it comes to melting snow, the XGK does it twice as fast as the Whisperlite. On a separate note, a hanging stove which uses a cartridge heats both your tent and water. Flaming plastic and spastic screams optional:p [and the XGK sounds like a mini jet engine, hence the description]

Ridge
12-20-2004, 00:24
It's amazing how many hikers I see, mostly day or section hikers, who wear cotton items, and this includes jeans. Cotton in winter is a Killer, period. No hiker should have on any item made of cotton. You can get good winter wear, even at second hand stores. I've purchased silk, polypropylene and wool items there. Hikers should also be careful with down sleeping bags and clothing. Wet down will NOT keep you warm, and is hard to dry. Experience will keep you alive, get it safely.

A-Train
12-20-2004, 01:05
The person who started this thread mentioned buying expensive under armour. Unfortunately, though I hate Wal-Mart and DO NOT shop there regularly, and certainly don't like advertising for them (not like they need it), but they sell an excellent cheap alternative. I bought a no-name brand long sleeve shirt, seemingly identical to under-armor for 8 dollars. It weighs 6 oz and is incredibly warm. I wear it many days in Vermont as a base layer. They also sell the Starter brand version of this for about 25 dollars.

Blue Jay
12-20-2004, 08:39
The person who started this thread mentioned buying expensive under armour. Unfortunately, though I hate Wal-Mart and DO NOT shop there regularly, and certainly don't like advertising for them (not like they need it), but they sell an excellent cheap alternative. I bought a no-name brand long sleeve shirt, seemingly identical to under-armor for 8 dollars. It weighs 6 oz and is incredibly warm. I wear it many days in Vermont as a base layer. They also sell the Starter brand version of this for about 25 dollars.

Man are you brave, admitting to going to Walmart. Clearly that's worse than pissing in the water source, then going to Uncle Johnny's with Wingfoot and two dogs. AHHHHHHH.

kncats
12-20-2004, 11:39
The idea that sleeping naked is warmer than with clothes is the trail version of an urban myth that goes back 20 some odd years. It violates some basic principles of physics and thermodynamics. The insulative value of clothing (and sleeping bags) is measured in units called a clo. Clo values are additive, just like R values are. A naked body has a clo of 0.0, typical clothing that you would wear in the winter (long sleeve shirt, heavier pants) has a clo of 1.0. If you add another layer of clothes the total clo value increases. Add a sleeping bag liner it goes up some more.

Bloodroot
12-20-2004, 12:19
The idea that sleeping naked is warmer than with clothes is the trail version of an urban myth that goes back 20 some odd years. It violates some basic principles of physics and thermodynamics. The insulative value of clothing (and sleeping bags) is measured in units called a clo. Clo values are additive, just like R values are. A naked body has a clo of 0.0, typical clothing that you would wear in the winter (long sleeve shirt, heavier pants) has a clo of 1.0. If you add another layer of clothes the total clo value increases. Add a sleeping bag liner it goes up some more.
Maybe I'm wrong, but the sleeping bag system works on the principle of capturing the heat your body produces. This heat is trapped in air space (the reason why loft from down bags are the ideal method to use; besides compressability). So, less clothes you have on, the more heat can enter this air space?

The Old Fhart
12-20-2004, 13:01
I've got to agree with Kncats. If I'm just standing outdoors and I get cold, I put on my down parka. I do not take everything I'm wearing off before I put the down parka on-doesn't make any sense. Where I would remove my base layers is if I've been hiking all day and my clothes are sweaty. After I've set up camp and have stopped sweating, I can take my sweaty clothes off and put dry ones before I get cold or before I get into the sleeping bag. If you're on a multi-day trip your sleeping bag could get progressively wetter as sweat enters the bag and freezes. This makes the bag heavier and less effective as an insulator. I've read stories of old-time arctic explorers whose sleeping bags ended up weighing 50 pounds after a long stay in the cold. Also as the sweat evaporates, your body is going to be cooled by the process. Under extreme cold conditions is where vapor barrier clothing as a first layer actually works.

I remember in 1987 getting to the top of Roan Mountain, in a storm, after dark, with 6 inches of snow on the ground and staying in the cabin. I took off my wet polypro shirt and put on dry clothes before getting into my sleeping bag. The temps hit 20 degrees that night and when I got up the next morning my long-sleeved poly shirt was frozen solid. It took me a half-hour to get up the courage to put that back on before I started hiking that day.

kncats
12-20-2004, 13:14
Maybe I'm wrong, but the sleeping bag system works on the principle of capturing the heat your body produces. This heat is trapped in air space (the reason why loft from down bags are the ideal method to use; besides compressability). So, less clothes you have on, the more heat can enter this air space?
Sure. And the more heat that enters one side of the sleeping bag then the more that is going to go out the other side. The insulation value of the sleeping bag isn't going to change, clothes or no clothes. That's a physical property of the insulating material. It's the total value of the insulation between your skin and the outside air that matters. Adding a layer of clothing increases the amount of insulation.

Glee
12-20-2004, 13:29
I’ve been reading so much about how to stay warm in winter it’s driving me nuts. When I was in the army in Basic Training they told us to sleep naked in the mummy bags. It was @10 degrees and lower at the time. The 1st night everyone slept with everything they could find and froze. The next night we all got naked and slept fine. (Well until someone threw in a tear gas canister) I’ve been trying different combinations for the last 1 ½ months sleeping outside in a hammock, (Sometimes setup as a bivy) with a fly and without. I’ve setup on the bare ground with just a ground cloth, (No Hammock) with and without a tarp. I have several different types of sleeping pads from closed cell to Therma Rest and Big Agnes. I have 3 different sleeping bags and the weather has been from the high teens to 40 degrees, with heavy fog and rain. I’ve been trying out a vapor barrier liner for sleeping bags, using rain gear as a vapor barrier, using rain gear as VBL with all my clothes on and no sleeping bag. 20 Degree bag and naked, and a host of other combinations. Each night I try something different and have started a diary to try and help me see what works best.

I think it was Warmlite which said, where a synthetic bag if it gets wet is harder to dry and will not keep you any warmer. Anyway, It’s a no brainer that you want to keep everything dry. The trick is how to do this in the many conditions and situations a hiker finds ones self in on the trail. I just finished spending 6 months on the AT and even after listening to hundreds of hikers talk of their experience and even my own, it’s still a learning experience.



I also read a post here where someone said that to get a hypothermia person naked and get in a sleeping bag with them. However, now I’ve read where this is not a good idea…(Getting them naked) Yes get them out of the wet clothes, but then if there is dry clothes to be put on, then? So, who’s right?



What is needed is for some of these companies, which are making major bucks off of us to set up a real climate control lab. Wind, rain, snow and sub freezing conditions. (I would love to use some of their top brass as subjects) Anyway, test this stuff (Tents, sleeping bags, clothes) in various conditions with real hikers and campers. Have treadmills to see how it works when we sweat. See how it works wet and how long it takes to dry. I know there is gear test web sites that people write reports, but to me they really don’t have what is needed to really give us an accurate report on all the conditions, (Real temp, wind speed, dew, ect)

Anyway, you get my point and enough of this rant…

Bloodroot
12-20-2004, 13:33
Adding a layer of clothing increases the amount of insulation.
And decreases the amount of radiating heat molecules entering the bag to produce the "furnace". Really not trying to disagree with you, just seems like putting on many insulating layers of clothing decreases the chance for the bag to do its job.

weary
12-20-2004, 14:04
And decreases the amount of radiating heat molecules entering the bag to produce the "furnace". Really not trying to disagree with you, just seems like putting on many insulating layers of clothing decreases the chance for the bag to do its job.
I carried a down sleeping bag liner when I hiked in '93, starting April 13. I don't know its rating, but it weighed less than 2 pounds and was at least 20 years old. When used by itself, the bag is comfortable down to about 50 degrees. Temperatures dropped well below freezing both in the south and during September-October in Maine and New Hampshire.

I supplemented the bag with a down jacket, wool socks, and insulated long johns. Insulation is insulation whether it is part of the sleeping bag or from clothing worn inside the bag. The only way extra clothing could cause one to sleep colder is if the bulk of the clothing cuts off circulation.

Almost every winter for the past 35-40 years I've winter backpacked in Maine in temperatures that routinely drop well below zero. I carry a zero degree sleeping bag and augment it with the same down jacket and insulated long johns that I carried on the trail 12 years ago. I've been chilly at times, but never chilly enough to prevent sleep or to cause danger.

One should carry dual use items on the trail in the interest of reducing pack weight. A jacket and long johns that serves to provide comfort in the evenings and supplemental warmth at night and thus permitting a lower weight sleeping bag makes sense. Colin Fletcher wrote excellent trail and gear guides. But he started the rumor that more insulation from clothing makes one colder at night and it has evolved into a persistent trail myth, apparently even believed by some Army training personnel.

Weary

kncats
12-20-2004, 14:13
And decreases the amount of radiating heat molecules entering the bag to produce the "furnace". Really not trying to disagree with you, just seems like putting on many insulating layers of clothing decreases the chance for the bag to do its job. Yes, adding layers of insulation in the form of clothing reduces heat loss occurring due to your sleeping bag. Effectively, you're improving the rating of the sleeping bag.

Weary - Colin Fletcher started that?! I'm shocked. He's my hero, even if he did think nothing about dragging a 60 pound pack around for thousands of miles. Was that in Complete Walker I? I don't recall seeing that in II through IV.

Footslogger
12-20-2004, 14:28
4. Yes, adding layers of insulation in the form of clothing reduces heat loss occurring due to your sleeping bag. Effectively, you're improving the rating of the sleeping bag.===========================
You might get some arguments on this last note. Up to a point, depending on the fabric being worn and the number of layers you could be correct. But, like in many area of life, too much of anything can be a problem. Wear too many layers of clothing and you could generate perspiration, which is not desirable.

In years of working for an outfitter and participating in considerable research/gear testing, it is my experience that the most efficient way to sleep is in a bag with a rating that is appropriate for your body's warmth characteristics AND that has adequate dead air space. The insulating properties of the sleeping bag combined with the dead air space inside the bag should provide the needed warmth without wearing excess clothing.

'Slogger
AT 2003

SGT Rock
12-20-2004, 14:43
[font=Times New Roman][color=black][font=Tahoma] When I was in the army in Basic Training they told us to sleep naked in the mummy bags. It was @10 degrees and lower at the time. The 1st night everyone slept with everything they could find and froze. The next night we all got naked and slept fine.

More than likely this is because everything the Army issues comes in cotton. I have experienced similar phenomenons, but I would rathr wear a nice set of polypro longhandels in the sack because you will be warmer than naked. Also, Army sleeping bags generally suck ass.

weary
12-20-2004, 14:52
Weary - Colin Fletcher started that?! I'm shocked. He's my hero, even if he did think nothing about dragging a 60 pound pack around for thousands of miles. Was that in Complete Walker I? I don't recall seeing that in II through IV.
It was definitely Colin. But I don't remember where. It might have been in an account of one of his hikes. I actually believed him at first -- and damn near froze.

While I'm on this subject the claim early in the thread that soda doesn't hydrate strikes me as wrong. Another poster claimed simple carbs provide quick energy. Soda is nothing but water and simple carbs (sugar), fizzing with a bit of CO2.

In the interests of full disclosure, I should probably admit to always wearing some cotton, summer and winter. Until it wore out my favorite winter jacket (from LL BEan) was made of 100 percent long fiber cotton. The fibers swelled up with the first rain and it became virtually waterproof -- except where your pack rubbed against it. Later they sold a similar jacket out of 60-40 cloth, part cotton, part poly. It didn't work as well.

The first backpacking tents were also made of long fiber cotton for the same reason. Cotton, like down, is a perfectly good fabric, providing you keep it dry. I continue to wear a cotton tee shirt most of the time. I try to minimize sweating while hiking by removing layers as needed. When I stop I put on my down jacket and usually the cotton tee shirt drys itself quite quickly.

No. I don't advise others to wear cotton. I know it can kill when used improperly or carelessly. I just like it.

Weary

Bloodroot
12-20-2004, 15:18
More than likely this is because everything the Army issues comes in cotton. I have experienced similar phenomenons, but I would rathr wear a nice set of polypro longhandels in the sack because you will be warmer than naked. Also, Army sleeping bags generally suck ass.

I'm sure this is where I am deriving my mentality. Still having nightmares from the field exercises in my Jan-Feb mobalization in Ft. Drum.

Glee
12-20-2004, 19:43
More than likely this is because everything the Army issues comes in cotton. I have experienced similar phenomenons, but I would rathr wear a nice set of polypro longhandels in the sack because you will be warmer than naked. Also, Army sleeping bags generally suck ass.
I was hoping the Army might have changed as this was close to 35 years ago.



During my experiments this past 6 weeks I have done the no clothes to VBL with different layers on top of the VLB, and everything in between. To be honest, I really haven't come to a decision as of yet as has this thread as to what works best and when.

orangebug
12-20-2004, 21:49
Getting naked removes wet clothing from the cold hiker. This allows the hiker to warm up the sleeping bag without causing cooling from evaporation of water in the wet clothing. Once the hiker is warmer and resuscitated, the hiker can begin to bring some of the wet clothing into the sleeping bag to dry. Of course, warm dry clothes would be warmer than being naked, but naked is better than wet.

Nameless
12-22-2004, 07:41
Hello,

In my original post I commented on getting a person naked and into a sleeping bag with another person. Yes, the main goal here is to get the person dry and starting to get them warmed up. So dry clothes seem as if they make the most sense, more warmth to the person.

But in a scenario where you are stripping someone down and getting them into a sleeping bag with another person, the first person, with hypothermia, does not have enough heat for clothes to function. Clothes work my insulating us from the surrounding temperature, it is your heat escaping you being held to your body by clothing that keeps you warm, not the clothing itself.

In that sense, clothing would only act as a barrier between the warm person without hypothermia and the hypothermic one. The warm person is acting as the heater in the bag, trying to bring up the temperature of the other person so they survive. A hypothermic person thrown into a bag alone has no source of heat, and therefore will not warm up.

On being in a sleeping bag alone on a normal night, you bet i will have my long underwear on, and if needed a fleece coat, hat, and mittens. One more layer of insulation to keep me warm.

Thanks
Pink

jlb2012
12-22-2004, 08:34
In browsing the net I came across an excerpt from the NOLS WFA book about hypothermia - for what it is worth: http://www.nols.edu/store/books/nc_wildfirstaid.shtml#hypothermia
you may want to scroll down a ways to the treatment options section.

note I have absolutely nothing to do with NOLS and in general I don't particularly approve of them but the excerpt did not appear to be too far off the mark.

The Old Fhart
12-22-2004, 13:21
The recommendation of putting a functioning warm person in a sleeping bag with a hypothermic one basically gives you 2 hypothermic people. First of all, putting 2 people in a sleeping bag meant for 1 compresses the insulation making it far less effective. Also if the heat transfer to the hypothermic person is sufficient, then the warm person, whose metabolism is dropping due to inactivity, will probably be cooled enough by conduction to become hypothermic themselves. Shivering is the body’s mechanism to produce heat so putting a dry shivering person in a sleeping bag will probably be sufficient to re-warm them. Using warm drinks and hot water filled bottles will also help. Never put anything too hot against the skin because you can cause burns without the person knowing it because their sense of touch and warmth have been compromised as well.

Hypothermia is the loss of body heat faster than it can be replaced. If the body’s core temperature drops about 3 degrees, to 95 degrees, you have symptoms of hypothermia like shivering. There will be signs of the level of consciousness changing, the person may become withdrawn. As the core reaches 90 degrees you have loss of coordination and the person becomes confused, the “umbles” set in. You don’t need to know what happens below 90 degrees, it only gets worse. It is interesting to note that a person with low body fat and low metabolism, like a nursing home patient, can become hypothermic sitting in an 85 degree swimming pool. You don’t need cold temperatures for hypothermia, only heat loss from the body’s core. Also note that you can get frostbite without being hypothermic if a local area, like fingers, are allowed to freeze.

Most of the problems in the White Mountains occur in the summer with temps around 50 degrees with wind and ill-prepared hikers. Generally winter hikers are better prepared although I have seen frostbitten hikers in cotton seek help at 9pm from the Mt. Washington Observatory where I worked in winter. The best cure is prevention and that means hiking with others because you won’t recognize when you are hypothermic because it is affecting your brain.

Youngblood
12-22-2004, 21:14
Maybe I'm wrong, but the sleeping bag system works on the principle of capturing the heat your body produces. This heat is trapped in air space (the reason why loft from down bags are the ideal method to use; besides compressability). So, less clothes you have on, the more heat can enter this air space?
Bloodroot,

What I think what you are missing is that you are trying to maintain the heat you generate, not warm your sleeping bag. So adding clothes, adds insulation, keeps you warmer... although your sleeping bag may not be as warm.

Youngblood

Lilred
12-22-2004, 23:32
Bloodroot,

What I think what you are missing is that you are trying to maintain the heat you generate, not warm your sleeping bag. So adding clothes, adds insulation, keeps you warmer... although your sleeping bag may not be as warm.

Youngblood

I can only speak from experience. The night I spent on top of Tray Mountain was very cold. It was Nov., and the wind was whipping right into the shelter. I had on my long johns, socks, and a fleece pullover and about froze in my 20 degree down bag. I finally took off the fleece pullover and the socks and warmed up very nicely. I was good as toast after that.

Youngblood
12-23-2004, 11:24
I can only speak from experience. The night I spent on top of Tray Mountain was very cold. It was Nov., and the wind was whipping right into the shelter. I had on my long johns, socks, and a fleece pullover and about froze in my 20 degree down bag. I finally took off the fleece pullover and the socks and warmed up very nicely. I was good as toast after that.I believe you experienced what you say. I also believe that with all other things being equal that wearing dry insulating clothing while in your sleeping bag will increase your warmth… it is basically the layering principle where you add layers to increase warmth and reduce layers to decrease warmth. Where there other factors involved that you overlooked… covering your head, zipper draft tubes in place, shoulder and hood cords cinched, physical exertion, drinking water, eating food, laying on clothing because sleeping mat wasn’t insulating enough, using clothing to shore up thin spots in your sleeping bag, the wind dying out, the temperature changing, etc?

Bloodroot
12-23-2004, 15:53
Yes, I definitely stand to be corrected. The concept is logical and easy to understand, but my experiences (like Lilredmg) for some reason lead me to feel different. Likewise, I always a sleep in thermals and usually stay toasty. Now Im not gonna exaggerate and say that I've never froze my ass off using this method ;). I always up for a good educating from those who have been there done that much more than I. Also, thanks Knats for not calling me out on the "heat molecules", it not unusal to overdose on dumbass pills from time to time.

White Oak
12-23-2004, 17:24
My experience is the same as Lilredmg. I've always been warmer in my down bag with few or no clothes on. I've tried sleeping with polypro layers and wool socks, only to take them off in the middle of the night and get warmer.

Theory is one thing, but experience is often different.

The Old Fhart
12-23-2004, 20:02
If you believe that you will be colder in a sleeping bag with more insulating layers on then you also have to believe that you would be colder if you put one sleeping bag inside another which isn't the case. Check how sleeping bags are rated and you will find the higher the loft (i.e., thickness), the warmer the bag. Doesn't matter if it is one or more bags to get the loft, the thicker the warmer. It may come as a shock to some but Holofill and down are not insulators, it is their ability to create minute air pockets that makes the sleeping bag or parka “warm.” I have a 35 degree down mummy bag that fits me without compressing the insulation. I also have a zero degree long and wide down bag that will fit over the 35 degree bag perfectly. Putting the 2 together gives me about a –40 degree bag. Even with these 2 bags together if I’m on the ground at +50 degrees my back is going to be cold because the insulation underneath me is compressed to almost nothing. The top and the bottom have the same amount of insulating material but the difference is the loft or thickness of the trapped minute air pockets.

The reason Thermarest puts the open cell foam inside their mattresses is to prevent heat flow by air currents in the inflated mattress. It would be cheaper for them to leave the foam out but the mattress wouldn’t be as warm, same principle as the sleeping bag. Has anyone ever had an inflatable sleeping pad go flat in cold weather? Doesn’t take long to realize it, does it? Here again you have the same amount of insulation inflated as flat but the difference is the amount of trapped air in the loft of the pad that insulates you from the ground.

If you’re a knowledgeable hiker and you are getting cold, you put on a layer like long sleeved polypro shirt. If you are still cold, you put on another layer like fleece. I don’t know any hiker who would take off all their base layers (assuming they are all dry) before putting on a down or synthetic filled parka thinking that that would be warmer.

For those who were cold and got into a sleeping bag and believe taking clothes off made you warm, if you had left your clothes on, you would have warmed up eventually, this has happened to me many times. Getting into the sleeping bag has decreased the heat flow from your body to the outside. If the bag has a sufficiently low rating, you will produce more heat than is leaking to the outside and you will warm up. Later, if I start getting too warm, I take off a layer or unzip the bag a little.

Sleeping bags and parka are not magic, they don’t store or create heat, your internal furnace does. Like any furnace, it needs fuel. One of the main causes of hypothermia is failure to eat and drink properly. That is why in winter camping I shift to higher fat, slower burning fuels like greasy sausages, peanut butter, and mashed potatoes with lots of Squeeze Parkay, etc.. I drink often because when you have the sensation of thirst you are probably down a quart already. Monitor your urine output. Yellow snow is good, orange (and other colors :) ) are bad because orange indicates dehydration has set in. As your blood gets thicker, it can carry less oxygen to the cells and you are likely to go into oxygen debt and develop cramps. This happens and it really takes a full day to totally recover.

There have been several very good posts on here based on science. Follow their advice or read a good book on winter hiking and you should be alright. Anything that sounds counterintuitive (like stripping before getting into a sleeping bag) is generally wrong, anecdotal, and based on bad science.

White Oak
12-23-2004, 21:12
[QUOTE=The Old Fhart]If you believe that you will be colder in a sleeping bag with more insulating layers on then you also have to believe that you would be colder if you put one sleeping bag inside another which isn't the case.

For those who were cold and got into a sleeping bag and believe taking clothes off made you warm, if you had left your clothes on, you would have warmed up eventually, this has happened to me many times. [QUOTE]

My observation isn't based on belief or theory, it's based on experience. I'm warmer in my down bag with no clothes on.

As I said before, I've tried sleeping in clothes, and instead of warming up eventually I was chilled. After several hours (with temperatures steadily dropping through the night), I took those clothes off, and was warmer and more comfortable with just me and the bag.

Youngblood
12-23-2004, 21:40
...My observation isn't based on belief or theory, it's based on experience. I'm warmer in my down bag with no clothes on.

As I said before, I've tried sleeping in clothes, and instead of warming up eventually I was chilled. After several hours (with temperatures steadily dropping through the night), I took those clothes off, and was warmer and more comfortable with just me and the bag.Well, my observations and experiences are just the opposite of yours and mine agrees with the theory of additive insulation.

Youngblood

Pencil Pusher
12-23-2004, 21:42
Theory is one thing, but experience is often different.
Exactly. It's a sword that cuts both ways and doesn't prove anything one way or the other here. Nevertheless, this very subject is one argued amongst the Boeing geeks of this local climbing club.

White Oak
12-23-2004, 22:18
Exactly. It's a sword that cuts both ways and doesn't prove anything one way or the other here. Nevertheless, this very subject is one argued amongst the Boeing geeks of this local climbing club.
I suggest we talk more about our actual experiences, rather than our theories. Like a pretty girl, a theory no matter how elegant is an unknown performer until a night in the sack. :D

Ridge
12-23-2004, 22:44
Water/Sweat and cold are a deadly combination. But even relatively mild temperatures can leave an outdoor enthusiast facing hypothermia, a chilling condition that left untreated quickly can deteriorate from uncomfortable to deadly.


When hypothermia occurs, the victim becomes cold from the inside out. That infringes the normal operations of the Big Three: heart, lungs and brain. When they become chilled, bad things happen.

Early signs of hypothermia often include hard or uncontrollable shivering and/or slurred speech followed by loss of fine motor control. As the condition worsens the victim may become irrational and non-responsive.

Basic treatment is warming the person. If the victim is wet, remove all wet clothes immediately.

This is critical to stopping heat loss. Then dress the person in something dry — preferably a change of clothes, blanket or sleeping bag. If no dry clothes are available, wring out as much water as possible and put them back on quickly.

Stuff whatever you can find that is light and dry — grass, leaves, even crumpled paper — between the skin and the damp clothes to provide some insulation. Move the victim to a warm environment as soon as possible.

Prevention, however, is the best guard against hypothermia. Dress in layers, using synthetic or wool garments. Avoid cotton, which has virtually no insulating or warmth value when wet. And you don't need to fall into the lake to turn a cotton undershirt or a pair of jeans into a hypothermia wrap. Clothing that is damp from perspiration is a cold conduit.

Keep exposed skin (neck, hands and head) covered and avoid direct exposure to the wind, as wind chill can become a killing factor.

Winter sun is a precious commodity. Keep track of how long it will take to return to camp or trailhead and leave ample time to get there before dark.

The best strategy is to prepare for the worst and do your best to see that it doesn't happen.

Carry a survival kit (long underwear, socks, knit cap, packable fleece pants and jacket and lightweight rain gear, small flashlight, fire starter and matches, candle, first-aid kit and energy bar). Seal the survival gear in a waterproof bag.

The Old Fhart
12-23-2004, 22:54
Interestingly some people confuse years of testing and experience by literally thousands of people as “theory”
Originally Posted by White Oak
Theory is one thing, but experience is often different.

Pencil Pusher-Exactly. It's a sword that cuts both ways and doesn't prove anything one way or the other here.
However, lets look at the facts. A quick Google check will give you:

Mountain Equipment Co-op
Like most manufacturers, our ratings assume you're using a sleeping pad and a tent. To increase the warmth of a bag, you can use an overbag or bag liner.

http://www.sierradesigns.com/bags.care.html#6
One misconception about sleeping bags is that they generate the heat necessary to keep your body warm. Of course, this is not the case, as a sleeping bag is an insulator—it will keep hot things hot and cold things cold.

http://www.cheaptents.com/AdSleep.htm
Sleeping Bag Liners can add up to 15 degrees of warmth to your sleeping bag, making it possible to use your sleeping bag in colder weather. I could continue quoting many more sites but if you believe the exact opposite of decades of testing and solid scientifically proven and logical evidence, there is nothing more I can say to convince you. An individually unrepeatable observation is not worth much. People used to believe the world was flat (and some still do-click here (http://www.flat-earth.org/) ) but scientific evidence proves otherwise. If I'm camping and I’m cold, I go with science every time.

weary
12-23-2004, 23:20
=White Oak
My observation isn't based on belief or theory, it's based on experience. I'm warmer in my down bag with no clothes on. As I said before, I've tried sleeping in clothes, and instead of warming up eventually I was chilled. After several hours (with temperatures steadily dropping through the night), I took those clothes off, and was warmer and more comfortable with just me and the bag.

My experience has been to crawl into my sleeping bag whenever it is convenient to do so. If after a few minutes I still feel cold, I add some more insulation (clothing), and keep adding more insulation until I am warm. This process has worked every time now for about 60 years.

The laws of thermodynamics -- or whatever they are called -- have been known for countless decades. White Oak your's is truly a most amazing discovery. I would document it, submit it to the scientific journals, and you will be obviously eligible for a Noble Prize -- I think currently worth about a million bucks, plus a free trip to Norway.

I don't doubt your observations. I just urge their documentation. I once wrote a book that insisted that when owners add insulation to their houses, the energy needed to heat those houses decreases. I am truly fascinated that the opposite may be true.

Let me, however, suggest a couple of things to check. If the clothing one wears to bed are damp from hours of hiking in the woods and mountains, perhaps the chilling effect of the dampness outweighs the insulating value. This also is a common phenomenon. Once many years ago I spent several months, courtesy of the U. S. Army, in the desert of Arizona. There "swamp coolers" were common. Buildings were cooled by having a sponge-like material rotating through a basin of water and the water evaporated by a fan blowing through.

I can envision something like that happening with damp clothing in a windy environment. Check also that the combination of sleeping bag and clothing might possibly be cutting off circulation of the blood in your body. This has happened to me once or twice. If blood can't get to an arm or leg for instance it can't warm the member with the heat generated by the body's internal furnace -- you know, that only source of heat that keeps one warm.

Without heat, body parts most certainly will get chilled, possibly even frozen. And once frozen -- or maybe just chilled -- all the insulation in the world won't help. That's why thermos bottles were invented -- to keep the cold in and the heat out -- and vice versa.

Weary

Ridge
12-23-2004, 23:21
was performed by Hilter on Jews in concentration camps to help the German Military understand hypothermia. I heard this from my Uncle who served during WWII for the U.S. I don't know if this information has ever been placed before the eyes of the public, I just would like to know if it was true or was just another war tail by my dear old uncle. I'm not jewish, but I hope any information from such things be released only with the permission of the next of kin of the victims, no matter how valuable it could be to the rest of the world.

rainmaker
12-23-2004, 23:56
Ridge, I believe the experiments you referred to are mentioned in the tome " The Rise and Fall of the Third Reich".

minnesotasmith
12-24-2004, 02:10
Having read about them in summarized from myself. I cannot vouch that they were in Shirer's book (which I have read), although they might have been.

What is relevant about them that I remember is that young Jewish male concentration camp inmates were made increasingly hypothermic in repeated experiments, being released into the company of other inmates at the end of a day's chilling. One particular male used for these experiments was literally brought back to life over and over by body contact and massage by a group of older Jewish women, having been chilled day after day to an extent that death would have been considered guaranteed by then-current medical knowledge. His repeated survival under extreme conditions skewed the results of the tests to such an extent that the Nazis overestimated their own troops' survivability during winter conditions during the Russian Campaign. This subsequently lead to many avoidable German troop deaths, especially during the Fall Blau (Case Blue) Ukraine/Caucasus campaign of 1942-3, which included the Sixth Army's destruction at Stalingrad (now Volgograd).

oyvay
12-28-2004, 18:14
was performed by Hilter on Jews in concentration camps to help the German Military understand hypothermia. I heard this from my Uncle who served during WWII for the U.S. I don't know if this information has ever been placed before the eyes of the public, I just would like to know if it was true or was just another war tail by my dear old uncle. I'm not jewish, but I hope any information from such things be released only with the permission of the next of kin of the victims, no matter how valuable it could be to the rest of the world.

The next of kin were murdered! Data from involuntary experimentation should be destroyed and NEVER used. This is why you have to be informed by your doctor about any procedure, possible side effects and have to sign papers that you were told about it. Research for new drugs (viagra) are done with VOLUNTEERS that were told and were still willing to do it (they could back out at any time). The nazis didn't allow their "subjects" to quit. If you wish to see some of the results of the nazis "experiments" go to Washington DC and visit the Holocaust museum.
(Not all the test subjects were Jewish, the bas****s used Christians too.)