Who wants credit for this one?

[polar]

But it also takes energy to keep it warm, since it's taking heat that would otherwise go into muscles or organs.

This line of thinking is why this myth persisted. But think of it this way: if you put warm water in a vacuum insulated bottle, does it need any energy to keep warm for a few hours? Your body is obviously not a vacuum insulated bottle, but it still does a good job of insulating your bladder from the outside world.

[Wildernessjane]

I have to go a certain pace to generate heat, to me it is not fast, its just my normal hiking pace. If I go too slow I am much colder than if I just go my normal pace, so there is a safety factor in going your normal pace. You know what you need to do to stay warm...

Totally agree, and you have said it much better than I did in my post, I set a very steady pace the entire day. It does not change than much going up or down.

I suspect it’s not really about managing your temperature at all though. If you can’t make a minor laying adjustment to accommodate a drop in temps then you don’t have your systems dialed in at all (which is essentially what’s being said here since you have to go at a certain pace to stay warm). Throw on an extra layer and I promise you you’ll be able to go a bit slower. That said, I’ve noticed that I tend to fall into a very consistent and steady pace and when I’m asked to go significantly faster or slower for a sustained period of time it zaps my energy on a big day. Purely anecdotal though. Another thing that seems to drain the life out of me is stopping every hour for a five minute break, which is something some people really like to do. I’ll stash food in my pockets and eat on the fly. These things become so much more important in winter when everything is just harder. I’m doubtful that anyone on here who gets out regularly and pushes for summits in winter is truly all that “slow”.

[CaptCO]

Pretty cool picture

[Chicago Transplant]

I have to go a certain pace to generate heat, to me it is not fast, its just my normal hiking pace. If I go too slow I am much colder than if I just go my normal pace, so there is a safety factor in going your normal pace. You know what you need to do to stay warm...

Totally agree, and you have said it much better than I did in my post, I set a very steady pace the entire day. It does not change than much going up or down.

I suspect it’s not really about managing your temperature at all though. If you can’t make a minor laying adjustment to accommodate a drop in temps then you don’t have your systems dialed in at all (which is essentially what’s being said here since you have to go at a certain pace to stay warm). Throw on an extra layer and I promise you you’ll be able to go a bit slower. That said, I’ve noticed that I tend to fall into a very consistent and steady pace and when I’m asked to go significantly faster or slower for a sustained period of time it zaps my energy on a big day. Purely anecdotal though. Another thing that seems to drain the life out of me is stopping every hour for a five minute break, which is something some people really like to do. I’ll stash food in my pockets and eat on the fly. These things become so much more important in winter when everything is just harder. I’m doubtful that anyone on here who gets out regularly and pushes for summits in winter is truly all that “slow”.

I definitely agree with being more zapped going others pace. Faster and I am working harder, slower and I am at altitude longer with more start/stops. Steady is more comfortable than start/stop for sure. I also get more sore if I try and match someone else's pace as I am either extending or shortening my steps and working my muscles differently.

I think I understand what you are saying, and agree that if I wore more clothes and matched a slower pace I would still be warm, but that seems to me its more from insulation and not so much from generating heat. Its the same in buildings, more insulation = less energy to heat a home. I guess from my standpoint the issue with going a slower pace and not generating heat is because I am not pumping as much blood. My heart rate is lower and closer to an at rest heart rate. So yes, more insulation would still keep me warm but I would still be generating less heat.

[Sluglas]

But it also takes energy to keep it warm, since it's taking heat that would otherwise go into muscles or organs.

This line of thinking is why this myth persisted. But think of it this way: if you put warm water in a vacuum insulated bottle, does it need any energy to keep warm for a few hours? Your body is obviously not a vacuum insulated bottle, but it still does a good job of insulating your bladder from the outside world.

Now let's tackle the myth about 70% of your heat escaping from your head because heat rises.

[highpilgrim]

Now let's tackle the myth about 70% of your heat escaping from your head because heat rises.

The number is wrong, the concept is correct.

40-45 percent of body heat is lost through the head and neck due to increased blood flow in comparison with the rest of the body.

Only Mensans lose 70% through their noggin because of huge output capacity.

[Aphelion]

Now let's tackle the myth about 70% of your heat escaping from your head because heat rises.

The number is wrong, the concept is correct.

40-45 percent of body heat is lost through the head and neck due to increased blood flow in comparison with the rest of the body.

The military literature on this is just wrong, and comes from a single discredited study from the 50's. Heat loss through the head is a result of not wearing as much clothing on your head relative to the rest of your body. There's nothing special about the head/neck.

https://journals.physiology.org/doi/ful ... ossref.org

https://www.bmj.com/content/337/bmj.a2769

[12ersRule]

Now let's tackle the myth about 70% of your heat escaping from your head because heat rises.

The number is wrong, the concept is correct.

40-45 percent of body heat is lost through the head and neck due to increased blood flow in comparison with the rest of the body.

Only Mensans lose 70% through their noggin because of huge output capacity.

If an online IQ test says I'm a genius, is that good enough to get me into Mensa?

Not surprised by that 70% number, I always feel like I'm about to freeze to death without a hat on.

[highpilgrim]

If an online IQ test says I'm a genius, is that good enough to get me into Mensa?

Haven't you heard?? Everything is done online now. You can even become an epidemiologist there. Lots of peeps on here have graduated from just that program.

[highpilgrim]

The military literature on this is just wrong, and comes from a single discredited study from the 50's. Heat loss through the head is a result of not wearing as much clothing on your head relative to the rest of your body. There's nothing special about the head/neck.

Good to know. I try to learn something new every day and this day, thanks to you, I'm a success!

Thanks for the link.

[Wildernessjane]

I think I understand what you are saying, and agree that if I wore more clothes and matched a slower pace I would still be warm, but that seems to me its more from insulation and not so much from generating heat. Its the same in buildings, more insulation = less energy to heat a home. I guess from my standpoint the issue with going a slower pace and not generating heat is because I am not pumping as much blood. My heart rate is lower and closer to an at rest heart rate. So yes, more insulation would still keep me warm but I would still be generating less heat.

It seems like overall we have very similar philosophies on winter travel. Just to play devil’s advocate here though, is that necessarily a bad thing to be generating less heat and getting more warmth from insulation? As long as you are not wearing too many layers to where you start dragging or even worse sweating, that is. Wouldn’t that mean you don’t have to consume as many calories over the course of a really long day? And I have the same issue, by the way, with a very low pulse and top of that I have unusually low blood pressure so I get that the struggle is real. It’s taken me years to perfect my layering system.

Edit: That is of course unless your goal is to be able to drink more beer and/or eat more cupcakes. That I can understand.

[Trotter]

The input of the metabolic process is more important in this case. If you drink cold liquid, then your body would need to use energy to warm it up to body temperature. But if your drink is already at body temperature or warmer, then no extra energy is wasted.

And even that is such a small amount of energy used. Drinking a glass of cold water vs a glass of room temperature water uses about 7 calories.