instead of sleeping * on * a pad which has a flat surface, and your shoulders and hips have their pressure points... how about something completely different.

assuming you are a back sleeper:
take a tight T-shirt that fits you, overlay it on a sacrificial foam pad, follow the outline and make a cut-out of it. somehow attach that 2-dimensional foam cut-out of a T-shirt to your sleeping shirt, use velcro, buttons, sewing or clips.

make the bottom of the shirt cut-out a bit longer, to cover the lower back.

when you lay down on down back, you are only using just enough foam padding for your back, and none of the extra mattress space.

then all you need after that is a pillow, which as discussed in other posts can be a variety of clothes in a stuff sacs or air bag containers.

I'm thinking a shorty sleeping pad the size of a T-shirt is really all we need. why have a mattress that covers unused areas. It will look like back body armor. the advantage is that it you will not roll off the pad, it will serve as insulation, you can wear it INSIDE your sleeping bag, especially if you get those backless Big Agnes sleeping bags.

just a thought.

well, OK, I have nothing else to do , so here we go...
What about your arms and your legs ?
Forgetting that, you will probably find that you will sweat against that foam
another possible problem is that given the right situation you can get condensation on the floor (often mistaken as water penetration) so that would directly wet out your sleeping bag.
Besides , do you really sleep all night on your back ?
Franco

rethink the rethinking.

really

When I was young I didn't use a pad or ground sheet at all. Maybe we need to lighten our age?

Ken, 'thinking' in it of itself is hard enough. You ask too much.

My arms and legs dont need padding, just my pressure points on my back and hips. In a UL tent, I usually put my knees and feet up on my backpack, so that gravity will reduce any foot swelling.

Sweating against the foam, depends on the foam type, temp and type of shirt used. Im generally not a sweaty guy, i suppose that is remedied by ventilation of the shelter.

In the outdoors i do sleep solid on my back the whole time, at home with a fufu mattress its different.

I think the natural position for mammals is side sleeping. Ever see any mammals besides humans sleep on their back? It's not natural as far as I'm concerned, it does not keep the spine in neutral, that is not good. I'm a side sleeper and think that the side position with about 20 degrees of hip flexion requires about a 15-20 inch wide pad with perhaps a hour glass shaped torso pad would work for side sleepers. That could cut some weight.

When it's cold and my arm or leg go off the pad and lay directly on the ground they get cold, like they'll get numb after a while.

But I like the thought process here.

I don't sleep comfortably on foam pad, I use heavier air mattress. I could have air mattress just under torso where it's needed and foam the rest of area to keep warm.

I've slept in a float coat a few nights. This is pretty close to your idea but with closed cell foam on all sides. Worked pretty well.

I had a bit of condensation between my shoulder blades but that was about it. The coat fit fairly loosely so I think the moist air was able to escape as I slept. I'm a side sleeper and change positions often during the night.

I certianly wouldn't rule out your idea without trying it.

"I think the natural position for mammals is side sleeping. Ever see any mammals besides humans sleep on their back?"

Yes, my dog; and he snores when he does. Most of the time he sleeps on his side and sometimes on his stomach too.

Hmm... seems I do the same.

Most of the time I sleep on my side. And until just a year or so ago I mostly used a foam pad. Torso length only the past few years. Not as young as I used to be.

The only sore spot I get is at my hip, but I am pretty skinny so it is mostly bone down there. I have been pretty happy with my NeoAir. But I have been thinking about just using a NightLite and putting my partially inflated Kooka Bay pillow under my hip. Going to try that one of these weekends.

"I think the natural position for mammals is side sleeping. Ever see any mammals besides humans sleep on their back? It's not natural as far as I'm concerned, it does not keep the spine in neutral, that is not good. I'm a side sleeper and think that the side position with about 20 degrees of hip flexion requires about a 15-20 inch wide pad with perhaps a hour glass shaped torso pad would work for side sleepers. That could cut some weight."

Some mammals sleep standing up. If we could get that figured out, we wouldn't need any pad at all...

BM

It is a generalization that most mammals sleep one way or another. My dog sleeps curled up with his nose in his butt. I know in my family everyone has their comfort zone, primarily based on body shape and mattress type.

I looked up a thread from year 2000, everyone has a different fav, and some people rotate. http://www.thebackpacker.com/trailtalk/thread/6375,-1.php

My initial statement was that if you are already a relaxed back sleeper, may be the T-shirt back-side body-armor foam pad can be efficient in space for the torso.

When you cut out only what you need, by reducing weight, you can afford to go for a thicker pad such as .75 or 1 in, because the surface area is reasonably smaller.

Some people cut and round up the corners on their foam pads, I'm thinking go extreme and trim it to the outline of a long T-shirt. then attach it to the T-shirt.