sleeping in the extremes

[Thomas Conly]

I’m going to be winter camping this coming January in potentially -30F weather. It may or may not get that cold but I need to be prepared for it. After a lot of backyard testing I’ve found that I can sleep pretty comfortably in those temperatures but I still have two gripes.
First, I’m tired of breathing in cold air. I made a face mask with fleece, Climashield and silnylon to keep my face warm and to prevent frosting up. It works well but I breathe through slits that don’t warm the air. If I breathe through a fleece neck gaiter it frosts up and drives me nuts. Any solutions? I’ve heard that silk scarves don’t frost up. Is That true?

Secondly, I always have to pee at least once or twice a night when it’s cold out. I can’t figure out why my body hates me in the winter. I know that others have the same problem. Anyone found a way to kill the urge while sleeping in the winter?

[Chad Miller]

Warm breath:
Try wearing a cheap dust mask under your face mask. Punch a few holes in the dust mast to prevent C02 buildup

Have to pee:

Get a pee bottle, pee into it while still inside your bag. Dump it out in the morning.

[bj bretzke]

Have to pee:
Peeing in the middle of the night might suck but you will be warmer in the long run. Your body will not burn calories keeping unneeded fluids warm. It really does make a difference.

Into the Great White Open!
BJ

[Roger Caffin]

> Peeing in the middle of the night might suck but you will be warmer in the long run.
> Your body will not burn calories keeping unneeded fluids warm. It really does make
> a difference.

It really does NOT make any difference at all. Sorry, but that is just a myth. Your bladder is deep inside your body and all your 'guts' are at the same temperature. Since the organs surrounding your bladder are at the same temperature as your bladder there is no heat loss from your bladder. As a result, how much liquid it contains has no direct influence at all on how warm you are.

But … if you have this 'need to go' feeling you are very likely to be squirming around and unable to sleep. THAT may well result in you losing heat, or at least feeling cold. But that is quite a different matter.

Cheers

[Steven Evans]

Hey Thomas,
I hate breathing in the cold air aswell. I use a ninjaclava which helps out quite a bit but it can freeze up a bit. I remember there is a product called the Psolar Face Mask…or something like that. It looks to have a metal/mesh screen over the mouth.

I have no experience with it, but I've always been intrigued by the idea. This thread just reminded me of it…maybe I'll pick one up.

http://www.psolar.com/id5.html

[Alpo Kuusisto]

In Finland they sell this:
http://www.jonas.fi/tuotteet/tuotekuvat/p0901_beige.jpg
for the athmatic and people doing sports in the cold.
Similar in function to Psolar mask, way lighter and smaller, probably not quite as efficient.
There must be something similar available in US too.
For MYOGers: it's just stainless steel wire mesh. Density is close to frying pan splatter guards.

I have used it in sleeping bag but personally rather take in cold air than wear something that heavy on my face. Didn't Roger Caffin write something about breathing in to your sleeping bag hood?

This started to bother me:
When you pee in a bottle and keep it in your sleeping bag, doesn't it make you warmer? Air inside your bag is probably no more than 85F and the liquid starts at 98F.
So you divide your body mass in two pieces and that warms you up??

[Elliott Wolin]

In the old days we just put a thick wool mitten or sock (unused, I hope, but I don't recall) in the opening of the sleeping bag and breathed through it. I don't recall having problems.

[Michael Martin]

> Peeing in the middle of the night might suck but you will be warmer in the long run.
> Your body will not burn calories keeping unneeded fluids warm. It really does make
> a difference.

> It really does NOT make any difference at all. Sorry, but that is just a myth.

Roger, you're spot on thermodynamically (as usual). However, I've heard of a physiological reason why holding fluid in your bladder may in-fact make you sleep colder. The reason is that with a full bladder, your body will push more blood to the extremities, defeating the body's mechanism of preferentially cooling the arms and legs to preserve "core" warmth. Ironically, if this is true, having a full bladder may make you feel warmer as your hands and feet will have more blood flow, but your total heat loss will increase and you'll ultimately end up colder. :(

Sorry, I can't cite a reference at the moment, so we may have to chalk this one up to folklore as well. ;)

Oh…to the OP:

If you sleep in a floorless shelter, you can just roll over and pee in the snow. Dig a little pit if you're self-conscious about it.

Cheers,

-Mike

[Greyson Howard]

THANK YOU ROGER!!!

I'm no scientist, but I'd been thinking this for years when told the old adage of needing to pee making you colder. Now I know I'm not crazy.
I'd be curious to learn more about the possible physiological contributions to this belief also mentioned in this thread though.

[Matt Lutz]

I find that I need to drink a lot of water in the winter (including throughout the night) to keep my throat from getting harsh. I'd rather not wear anything over my mouth because of freeze up.

You can also dig a hole in the snow in your tent's vestibule and use that for midnight trips.

[Eric Blumensaadt]

For really cold nights I use a "Polar Wrap" mouth cover that has copper wire mesh inside to warm incoming air.

It does work well enough that I lose less moisture from respiration during the night and therefore don't get thirsty. Also I don't put as much moist air into my bag if I inadvertently breath into it.
I got mine from Cabela's.

[bj bretzke]

Since Roger popped my old wives tale bubble I've been thinking about it. Perhaps there is some psychological reason I feel warmer. Or perhaps getting cold while peeing makes it seem that much warmer when your done. I am a tentside snow hole guy at midnight. Just pondering…..

[Michael Martin]

Take a look at my post above. :-)

[bj bretzke]

Michael:
Thank you for supporting my fragile belief system!

BJ

[John S.]

I'd have to see Michael's reference (peer reviewed journal article hopefully), otherwise urine in your bladder having any real effect on blood flow to extremities makes no physiological sense to me.

[Michael Martin]

John-

It's not a peer reviewed study, but here is an interesting discussion of this subject:

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=5139&disable_pagination=1

It's been a while, but Roger, you, and myself all participated in that thread — way back in the olden days… ;)

/MM

[Steven McAllister]

I found that using a no-see-um net helps raise the air temp around your head enough to make a difference.

My experience is with an SMD Meteor bivy. Not only does it make the air I breath warmer it also tends to add a few degrees of warmth overall be reducing air circulation.

Any bug bivy or net attachment should add to the comfort for a few more ounces. I'd bet a head net would help?
Try it sometime.

[Barry P]

“If I breathe through a fleece neck gaiter it frosts up and drives me nuts. Any solutions?”

Well here’s what I do;
At 5F conditions, after I have closed the hood so only my mouth and nose is visible, I plop my packtowel over the hole. This takes a little practice. In the morning, this saves the bag from wet and frosted breath. The pack towel is wet and frosted but my face was able to sleep warm all night and the bag stays dry. It helps to be a back sleeper in the winter for this to work.

“…Anyone found a way to kill the urge while sleeping in the winter?”

Yea, I hate the urge. You have to experiment with your body on different meals because you don’t want to have too little liquid and too little calories or you will freeze. For example, I have found that I sleep warm and I kill ‘the urge’ if I just ate some hot Ramen noodles (I love the salt) and 2C of mildly-hot chocolate.

And for Roger “Since the organs surrounding your bladder are at the same temperature as your bladder there is no heat loss from your bladder. As a result, how much liquid it contains has no direct influence at all on how warm you are.”

Don’t you think it requires more energy to keep that extra mass at 98.6F? And that energy could have been better used elsewhere? And adding insult to injury, more energy is expended just by the brain telling you to go!

-Barry

[Michael Martin]

>> Don’t you think it requires more energy to keep that extra mass at 98.6F? And that energy could have been better used elsewhere? And adding insult to injury, more energy is expended just by the brain telling you to go!

Hi Barry,

It doesn't take any energy to keep a mass at a given temperature. There will be a negligible extra energy expenditure keeping the fluid in the bladder warm to the extent that the full bladder increases your surface area (by puffing out your abdomen.)

Take a look at the thread I mentioned above — there's a more complete discussion of this.

Happy New Year!

-Mike M

[Barry P]

“It doesn't take any energy to keep a mass at a given temperature.”

I wish you would tell my electric bill that :(.

And happy new year too!

-Barry

[Michael Martin]

>> “It doesn't take any energy to keep a mass at a given temperature.”

>> I wish you would tell my electric bill that :(.

Conductive heat loss in your home is through the surface skin of the house. If you fill up your bathtub with water at the same temperature as the air in your home, it won't take any more energy to maintain your house temp. :)

Cheers,

-Mike

[Roger Caffin]

Hi Barry

> Don’t you think it requires more energy to keep that extra mass at 98.6F?
Nope, not when the surrounding internal organs are also at 98.6 C. No thermal gradient from the interior of the bladder: no energy transfer from the interior of the bladder. Basic physics.

> And adding insult to injury, more energy is expended just by the brain telling you to go!
Ah … I'll pass on that one. Unmeasurable (and extremely small). I wonder though how it compares with the energy expenditure from dreaming, or from snoring?

Cheers

[Barry P]

“Conductive heat loss in your home is through the surface skin of the house. If you fill up your bathtub with water at the same temperature as the air in your home, it won't take any more energy to maintain your house temp. :)”

Good example for a physics lesson.

From Roger: “Nope, not when the surrounding internal organs are also at 98.6 C. No thermal gradient from the interior of the bladder: no energy transfer from the interior of the bladder. Basic physics.”

I think that’s the assumption: ‘no thermal gradient’ in a human body. But is our physiology really that simple? It has been suggested we have an internal gradient of 0.1C/cm. And here’s an interesting article “parameters such as density and heat conductivity of the various tissues and variables such as blood flow and metabolic heat production of different organs are spatially distributed and thereby influence the temperature profiles within the human body.” http://jap.physiology.org/cgi/content/abstract/65/3/1110

-Barry

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