20 tips on sleeping warm in the outdoors
-- by Greg Rouse
Sleeping warm is one of the factors that can make or break a cold weather adventure. Remember the body cools down during sleep and the blood is drawn from the extremities (feet and hands) to the center or core of the body, so proper insulation must be provided to prevent heat loss. For a good nights sleep on your next cold weather adventure, you may choose to use some or all of the tips below:
Keep hydrated during the day and avoid drinking lots of fluids at night, so you won’t have to go to the bathroom in the middle of the night.
If you must go, use a pee bottle, it’s better than exposing yourself to the elements (just make sure you label the bottle). Besides, holding it in requires your body to waste energy (calories) trying to heat up the water in your bladder to 98.6 degrees.
Eat a big dinner with lots of calories. Calories are a unit of heat, without them the furnace won’t burn hot.
Keep a snack with you for the middle of the night, so if you wake up cold you can replenish lost calories.
Go to bed warm. Warm up by taking a brief hike around camp or doing some jumping jacks. If you wrap a frozen salmon in a sleeping bag, will it stay frozen? Yes, because your sleeping will insulate cold or heat, just like a Thermos.
Select a protected campsite out of the wind and off the valley floor and other low areas where cold air settles. A good rule is to be ~50 feet above the valley floor.
Fluff up your sleeping bag with vigor to gain maximum loft before you climb in.
Use a good insulating pad between you and the ground. Studies show, it’s more important what you have under you, then what you have on top of you.
Where a stocking hat to bed, you lose most of our heat through your head.
Keep your nose and mouth outside your sleeping bag, your breath contains a great deal of moisture. Wear a balaclava or wrap a scarf around your face instead.
Roll the moisture out of your bag each morning when you get up (roll from foot to head), then leave it open until it cools to air temperature. If weather permits, set it out to dry.
Use a layered sleeping system (i.e. sleeping bag, liner, half bag, bivy sack). A layered system helps to remove the frost buildup that naturally occurs when your body warmth meets the cold air (a concern if you’re staying out multiple nights).
Avoid overheating at night and make sure you go to bed dry. Overheating produces perspiration, so vent your bag if needed or take off your stocking hat.
Make sure your feet are as dry as possible before going to bed. This can be done by having a pair of dry sleeping socks or polarguard booties in your bag for sleeping only. Also, you can “dry” wash your feet with a good foot powder that contains aluminum chlorohydrate, which helps dry the skin and reduce perspiration.
Use a “sleeping suit”, which is a clean and dry pair of long underwear stored in your sleeping bag.
Wear loose fitting clothing to bed so it doesn’t restrict circulation.
Keep your sleeping gear clean. Dirt clogs air spaces in the material and reduces insulation value.
If you have cold feet, sleep with your feet together in and elephant foot or half bag. It’s a bag that uses the principle of the buddy system, where the feet share heat instead of being isolated, much like mittens are warmer than gloves. The bag slips over your feet and legs and then drawstrings shut or you could just use a fleece jacket wrapped around the same area.
Fill a water bottle with hot water before you go to bed and then strategically place it at any cold spots in your sleeping bag. Just make sure it has a screw on lid like the Nalgene bottles. A variation of this is to use disposable heater packs or hand warmers, which costs a little extra money. Or, in the old days they would take some heated rocks from around the campfire and place them in a wool sock (just make sure there not to hot, so they don’t burn your sock and/or melt your bag).
Finally the old stand by, snuggle up to someone else or the Buddy System (shared warmth with others).
About the Author:
Greg Rouse has been teaching wilderness sports and emergency response at the university and college level for over a decade. He is also the founder of a unique web site called WildernessTrip.com, a one-stop resource for self-guided wilderness trip planning. This web site is basically; a free online guidebook that photo-documents trips with interactive maps and detailed route descriptions. Each trip has free pictures and free topographic maps of the trail, all in a print-friendly format. Check it out at http://www.WildernessTrip.com