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Pre-Hike Hydration: The Key to Staying Hydrated for Winter Hiking

Staying hydrated in winter takes extra effort
Staying hydrated in winter takes extra effort

Winter hikers and snowshoers often have difficulty staying properly hydrated in cold weather because winter hiking is physically more challenging and the physical act of drinking is more involved than simply sipping from a hydration hose, what with heavy winter gloves and insulated containers.

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 bottles in the morning to get it real hot, before slipping it into insulated water bottle holders that keep it from freezing for most of the day.

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, especially 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.

Boiling drinking water before a winter hike
Boiling drinking water before a winter hike

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 or flavored Gatorade 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 a flavored recovery drink mix to one of liters of water that I carry and to drink it at the beginning of the second half of my hike. My preferred electrolyte additive is Ctyomax with Maltodextrin so it provides me with an easily digested caloric boost without the spiky sugar rush of other drink mixes. I like to think of it as liquid food which makes drinking an entire liter of water at once a lot more appealing. It even tastes good when the water is still warm.

How do you stay well hydrated in winter?

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  1. Maltodextrin is not a sweetener, it’s a carbohydrate. That cytomax product has stevia in it. They have pure unflavored cytomax maltodextrin called Cytocarb which I’ve used for years as a liquid carb source.

    • Good catch – should have remembered that from my beer brewing days. Maltodextrin is short chain of molecularly linked dextrose (glucose) molecules and while it may be slightly sweet, it’s not used as a sweetener but as a carbohydrate element. Didn’t realize it was sweetened with Stevia, but luckily it doesn’t bother me.

  2. Wow, that sounds like over hydration to me. I totally support prehydrating with a 1/2L to 1L befor most hikes in summer or winter so I don’t have to cary as much water or stop quite as much while hiking. For most winter hikes, I get by with carying only 1.5 to 2L. Then I make sure to drink some extra when I get home or to camp, but with what you’re suggesting I’d be stopping every 15 minutes to go pee all day. I don’t find it necessary to force liquids and a little mild dehydration at the end of a hike is rapidly rectified with post hike drinking. If there is snow on the ground, I’ll also hike with a wide mouth bottle inside my jacket and add snow to my water bottle as I drink it so I don’t have to cary as much water, I don’t run out of water as fast, and since I generate plenty of heat while hiking, the cool slush mix under my coat is not a problem.

    • Maybe my definition of winter is different than yours. It’s a lot more than “snow on the ground” and the exertion level can be fairly extreme as we climb up mountains, snowshoe, or XC ski on trips that typically last 6-10 hours. I also guzzle a lot of liquid after a hike to rehydrate.

      The best way to determine your hydration level is to look at the color of your pee on the snow. If it’s clear (uncolored) you’re properly hydrated. If it’s yellow, you’re not. If it’s dark or brownish yellow, you are very dehydrated. Drink water as needed to keep the color clear.

  3. I like your idea of sipping from a water bottle in the car in route to the trailhead. We normally stop at Dunkin Donuts before we start out our drive for some sugary treats and coffee, but it usually takes about 15 minutes or longer before I can start drinking my coffee. I’m going to add the water bottle in the car to my routine. I typically throw a bottle in the way back of the car as extra water for the end of our hike, but now I’m going to add another bottle and keep it up front with me. Thanks for the tips about staying hydrated.

  4. But don’t forget, other things besides dehydration can affect pee color. Asparagus, Vitamin B supplements, etc.

  5. My winter hiking is in way milder weather than yours but I also “camel up” before any hike with a liter or two. For some reason, carrying liquids internally seems less onerous than in my pack. Studies have shown that during exertion, endurance and performance is enhanced by proper hydration. Sure, I have to stop more often because a flatter bladder is a gladder bladder but being hydrated helps keep this old body moving along the trail.

  6. I tend to drink a LOT more water when I’m snowshoeing. That high level of exertion makes me want to drink a lot more water naturally. But when I’m on a slower paced hike, it isn’t at all evident that I’m not taking in enough fluids.

    One thing I notice in winter time is that my lips are constantly chapped if I do not drink enough water, so that is a good indicator as well if your skin is dryer than normal (which it will be just due to the cold dry air).

    I find that taking an insulated mug of coffee with me in the early morning hours helps keep me warm and hydrated. There is nothing quite like the satisfaction of a good cup of coffee in the woods enjoying the scenery. Part of the ritual of morning coffee is manual brew methods and manually grinding the coffee myself. I take coffee pretty seriously!

  7. Very good reminder, need for h20 is not as striking psychologically in winter as it is in summer.

  8. I’ll add a few tablespoons of chia seeds to water, wait for them to fully hydrate, then drink the mixture (first thing in the morning). They absorb a ton of water then slowly release it in your system so that you can stay hydrated for longer than plain liquids. Also has a huge boost of calories, protein, fat, and fiber. Takes some getting used to, but even better with juices.

  9. Any thoughts on thermos flasks for UL/SUL rehydration purposes? I agree on the prehydration before a day outing, then continuous sipping and major intake after. This saves carrying weight. Similarly, prep landing foods as discussed to make hydration easy makes for tastier food. I love a nice hot drink sometimes but most thermos flasks weigh a ton.

  10. Winter hydration is trickier, I agree. Hydrating before any kind of strenuous activity is always smart. I guess I stick to the same routine as summer, which is to be drinking water before, during and after. It’s hard to say which season I lose more water in. I work harder in winter for the equivalent speed, but I move a lot faster in the summer and sweat a ton, as in streaming off my head.

    I’m as guilty as anyone but coffee dehydrates, probably not the best pre-hike beverage. But hell, I drink it on the way up and usually carry some with me anyway. You can’t get ready for a day out in the cold without the java juice.

    I still havent really found a good way to keep my water bladder valve from freezing up. Any thoughts on insulated water hoses? My impression was they didn’t really work that well.

    • The current theory is that coffee is just fine to drink before a hike and not dehydrating.

      As for insulated hoses. Forget that. Get bottles and insulation sleeves or bury them in your down puffy inside your pack for insulation.

  11. All good advice – besides my coffee, I drink a liter of water with EmergenC electrolytes in it on the way to the trail. Find this starts me off right.

    As a leader, I get concerned on both winter and summer hikes where a participant is out for 6-8 hours on the trail and never takes advantage of a “separation break”. Too many people don’t drink enough and get away with it – until the time they don’t.

  12. Outstanding advice, Phillip. I had a sports physiologist tell me that most people are clinically dehydrated on a daily basis.

    He suggested a good rule of thumb is to divide your weight in half and that is the number of ounces of water you should drink every day. This is for sedentary individuals and the amount increases with any type of physical activity.

    In extended high exertion activities you should pre-hydrate and continue to drink as you exert yourself. If you wait till you feel thirsty, your stomach cannot absorb liquids fast enough to repay the debt, leading to dehydration, which in winter adds decreased resistance to cold and hypothermia to the classic symptoms…

    • Same holds with food in winter. Your body can only absorb 250 calories an hour no matter how much gu you eat at once. You need to eat constantly in winter to keep up with the caloric demands.

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