As a cold sleeper, here is my answer to your question:
Whether your backpacking or car camping, you run into the same problem in the winter. During the day, no matter how much you try not to, your body will perspire, even when cold. Its part of being made up of ¾ of water. This water evaporates for the most part, but you still maintain some of that moisture in your clothing. That’s why we have things like UnderArmor and breathable outter layers. When your body is at rest it generates the least amount of heat, and the moisture in your clothing will, if it touches your skin, steal that heat away (water is a natural heat sink), making it harder to stay warm.
If you are a cold sleeper like me, which means that my core temperature at rest is lower than some, it makes it harder for your body to stay warm. I have to take every precaution to keep my heat contained. The best way for me to do this is to completely change out my base layer at bed time. For me that means, fleece long johns, wools socks and a fleece cap (and sometimes even liner gloves and down camp bootys). All must be dry. My feet and head must stay warm if I am to keep my core temp up and sleep well. There are plenty of light weight options (think down) for some of these items. I can usually fit them into a 4” x 8” compressed bag that weight about 1.5 lbs. Another benefit to doing this is that it keeps the inside of your hammock and UQ or sleeping bag cleaner. The more dirt and grime you have in your bag, or clothing, the less the insulation works, and the more moisture they will retain, cutting down on your warmth. Like a weapon, you want to keep it clean to keep it serviceable.
The clothing that I change out of is hung up at nigh to allow them to dry over night. This is another reason that hammock camping is cool. I have clothes lines all over the place. In the morning I change back into the previous days clothing, after giving them a good shake to knock off frost and critters. I then hang my night clothes out to air dry while my tarp is drying from the dew or frost of the night. If my day clothing is damp, that’s not terrible (except for the first few minutes), but I can do things to get my body heated up: Like drink a hot drink and eat high calorie foods, do some camp site chores, or sit by the fire (or my favorite – all of the above). Within an hour or so I’m good to go.
I envy the hot sleepers like my friend FatDaddy. I’ve seen him sleep in boxers in 0 degrees. He unzips his bag all night long to vent the steam that rolls out. “I hate that guy”. If you’re a hot sleep, you have the added concern of sweating all night long. Then it is a good idea to change your base layer every morning, and air dry your entire kit, just to keep it dry. But it’s not a bad trade off, if you never get cold at night.
That’s my two cents.
Aka - Roger-Dodger
Backpacker w/QRP Gear - Schofield WI
Above all else, it should begin and end with HONOR!