Sleeping Bag & Pajamas

Is my sleeping bag's performance affected by what I wear when I sleep?

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Is my sleeping bag’s performance affected by what I wear when I sleep?

Submitted by – Philip – Athens, GA


Absolutely. For the most part, your best bet is to sleep in your long johns. Not only does this keep the liner free from contamination (from your body oils, dirt, sunscreen, bug spray, etc.), it provides a wicking layer that will pull sweat away from your skin as you sleep, so you don’t get that clammy feeling.

If you’re cold, you might need to add another layer. For best results, go with thinner layers rather than big bulky ones. A sleeping bag actually works by trapping warm air near your body. If you overfill your bag’s internal space, there’s no room for that warm air to live (and insulate). Also, adding more layers means adding more bulk, which can lead to compressed insulation and cold spots. The key is to try to find your sweet spot: Just enough clothes to keep you warm, but not so many as to inhibit the insulation from fully lofting.

Here are some more tricks to staying warm while you sleep:

  • If your bag doesn’t have a draft collar—an insulated tube that fits around your neck to seal out drafts– wrap a piece of clothing around your neck to prevent cold air from sneaking in.
  • Go with a thick (up to 2.5 inch) mattress that has some insulation inside. Otherwise, you’ll lose a lot of conductive heat to the cold ground. Forget about those plastic blow up air mattresses—save them for the pool in the summer time!
  • Wear a wool or fleece hat to bed to prevent heat loss from your noggin.
  • Make a hot water bottle. From September to May, I always snuggle into my bag with a leakproof bottle filled with boiled water.
  • Eat a good dinner and stay hydrated. Your body needs food and drink to function properly and keep you fueled throughout the night.
  • When you have to pee, don’t hold it in. Get up and do it, no matter how cold it is outside. You’ll sleep warmer and better after you expel that extra liquid.