Name of Experiment: Be Brave, Get Naked!
Introduction: During my time in La Paz, I happened to have a conversation with a girl about the methods of being warm in a sleeping bag. She enlightened me with a theory that had been shared with her. It entailed the following: The less you wear inside your sleeping bag, the warmer you will be. The theory behind this being that the sleeping bag reflects the heat off your body, thus wearing clothes disables this process. The words of encouragement that came with this advice were "Be brave, get naked".
Bianca and I decided to test this theory during our time in Uyuni, Bolivia. We discovered upon that you could indeed be very cold inside your sleeping bad whilst wearing warm clothing - no less than 2 pairs of thermals, winter jackets, socks and jumpers. Both of us were quite shocked at this revelation.
Hypotheses: Sleeping in a sleeping bag naked will provide a warmer nights sleep than wearing clothing.
1 sleeping bag
1 cold night
1 private place to sleep (preferably)
1 set of warm clothes
1) Wait until one night that is exceptionally cold
2) Take off all of your clothing (underwear is permitted) and get inside your sleeping bag
3) Make sure the sleeping bag is completely closed up. Tighten the elastic ties around the hood and neck of the sleeping bag so that cold air cannot enter and warm air cannot escape.
NOTE: Do allow enough space so as not to disrupt breathing or circulation!
4) Proceed to sleep as normal
5) Observe results via comfort in body temperature levels throughout the night.
NOTE: Do not wake up purposefully to observe temperature. Allow this to happen naturally.
6) Repeat exercise wearing warm clothing
Process & Results: We tried this theory twice during our time in Uyuni and the surrounds. The first night of the experiment we stayed in a hotel entirely made out of salt - including our beds. It was indeed a very cold night. Gingerly we took off all the warm clothing we were wearing - to say the least it was unpleasant. Quickly we jumped into our sleeping bags and silk liners, shivering and waiting for the bags to warm up.
After the initial warming period it was indeed warm inside the bag. Although my skin was cool to the touch. I chose to continue to wear my socks, B however did not - which she highly regretted. In the morning we awoke to find that yes, we had been warm all night. Well, B was warm after she decided that socks were in fact a good idea.
The next night was considerably colder. We were in a very basic hostel at around 4300m above sea level surrounded by snow. We repeated the process and achieved similar results.
This experiment proved the hypothesis that "Sleeping in a sleeping bag naked will provide a warmer nights sleep than wearing clothing". However, there are a few potentially confounding factors that need to be acknowledged.
1) We had been drinking rum both nights we trialed the experiment, but not on the day we were trying to sleep with our winter clothes on. However the amount of alcohol consumed was not significant.
2) Both nights of the experiment we had a few thin blankets on top of the sleeping bags, however not on the control trial.
Antagonising the confounding factors is the fact it was considerably colder the 2 nights of the experiment than it was during the control trial.
To be sure of the results this experiment would need to be repeated with fewer variables. However I hypothesise that the results would be similar.
So next time you're spending a cold night in a sleeping bag, remember this motto. Be Brave, Get Naked!
Editors note: To avoid embarrassment and possible arrest: Avoid trying this experiment on an overnight bus or company camping trip.