What to wear under your sleeping bag for best results

Sleeping oudoors? Sleep under the stars, on hard jutty stones and having creepy crawlies snailing up your sleeping bag, to your face. And this is possible with proper gear. Buying it right, wearing it right…. and you’ll find yourself loving it just as much as your warm comfy bed back home. And once you have bought the right gear, you might want to know how to use it right too.

There are many theories discussed to how to keep yourself warm in a sleeping bag. You might think that wearing everything you have brought along on your trip will keep you really warm in your sleeping bag. You slip in your sleeping bag and feel how it warms you up. Once comfortably warm, you fall asleep only to wake up in the middle of the night feeling damp, sticky, cold and utterly uncomfortable. What happened? Lets take a closer look.

There are some who swear with a comfortable PJ layer or long johns. Even many altitude campers sleep naked in their sleeping bags. So whats the best? Putting on any layer inside your sleeping bag means that the heat produced from the body radiates only to the next layer, and if there is one, it will be absorbed by this layer and not directly into the sleeping bag. That reduces the radiation of your own body heat the sleeping bag is supposed to give back to you. More ever, sweat and dampness in the clothing (even though you think they are dry) will make you feel cold when trapped in the bag and can’t escape. You might wake up in the middle of the night and start to freeze or feel uncomfortable. A loose t-shirt works well for me. I am pretty sensitive at the shoulder and at some time in the night, usually fight my way through to get the arms free and out of the bag. Thus I’m much safer with a cotton t-shirt on top to prevent myself from waking up with a frozen torso. The motto is: the less, the better. If you shy from sweaty, sticky gooiy, stinky sleeping bags in the long run, you have two alternatives. Either get an ultra thin cocoon bag out of silk as an inlet, or shower before you sleep 😉 Airing your sleeping bag well the next day is also important to let the bad air out.

Not everybody can sleep naked. Sleeping in your birthday suit has a few disadvantages too. If it’s really freezing outside, a trip to the loo could make you lose all the cosy warmth you have built up the last hours in your sleeping bag. Depositing your base layers inside the sleeping bag ensures that you have your clothing handy when you need them, and that your body stays warm when you get out of the bag. At the same time, these clothing are heated up together with your sleeping bag through your body heat which makes it far more comfy to slip in the mornings.

So there you go. You can really choose whats best for you. In all cases the motto stays “The less the better”.

Read here, here and here, for reviews on synthetic Sleeping Bags I have slept in.