Winter hikers and snowshoers often have difficulty staying properly hydrated in cold weather because winter hiking is physically more challenging. The physical act of drinking is also more involved than simply sipping from a hydration hose, what with heavy winter gloves and insulated containers.
Even then forcing yourself to drink water regularly during the day can be difficult, since your perception of thirst is so different in cold weather than in warm weather. Perspiring in winter is far less evident, even if you’re managing your layering carefully. You also don’t realize that your body is working harder to humidify the air you breathe, which can also drain “your reserves” significantly during the course of the day unless you drink more fluids.
There are two tricks to drinking more than I’ve discovered over the years as a winter hiker and backpacker. The first is to pre-hydrate before reaching the trailhead. Before I start a winter hike, I drink 2 liters of liquid before I even start hiking. I do this by drinking a liter of coffee, milk, and juice over breakfast, and by sipping a liter of water in the car on the way to my hike. I pee more during the day, particularly in the morning, but it lets my body get ahead of the hydration curve rather than falling behind it. I swear by this technique.
The second trick is to add flavored herbal tea bags or a sweetener to my water so it tastes more appealing. I go through about 20 boxes of Bengal Spice tea and several bags of instant honey ginger crystals each winter. A little flavoring really increases your motivation to drink liquid during the day.
Preparation is the Key
I usually carry two or three liters of water on winter day hikes, depending on their length, since you can’t count on being able to resupply your water easily. I boil the water for my polyethylene bottles in an electric kettle in the morning to get it real hot, before slipping a wool sock over them. I then pack them inside my backpack next to my extra insulation layers, which keeps them from freezing for most of the day.
I’ve pretty much given up on storing bottles on the outside of my backpack because insulated bottle covers won’t keep them warm for more than a few hours. When I do carry insulated bottle sleeves, it’s usually on a shorter hike, or when I’m hiking with a group of hikers, which makes it harder to top whenever you feel like it for a water break.