Food and Nutrition for Winter HikingThe Importance of FoodNutritional requirements for a winter hiker are not that much different than they are for a summer hiker, or for any other athlete, for that matter. However, a lot of calories are required, on a winter hike, simply because of the extra exertion and the energy you want available to keep your body warm and moving. You need to drink liquids frequently and deliberately to avoid dehydration in the winter environment - water is required to metabolize your food, and thus to keep you warm and energetic. This permits you to better endure the physical and mental challenges of winter hiking. The following simple guidelines should help keep you well, energetic, and warm on the trail. Calorie Requirements On A Winter Hike An active winter hiker usually tries to lose heat rather than stay warm enough - at least, as long as he or she keeps moving! The energy demands of a winter hike do not depend as much on the outside temperature, but rather on your level of activity, body weight, weight of clothing and gear, and the type of terrain. You might burn a minimum of 100 extra food calories per hour (with a light load, traveling over flat, packed snow) up to 500 or more (with a heavy pack, on steep terrain with deep snow). A winter hike requires larger expenditures of energy than a summer one, and while energy output can be moderated by various means (for example, by adjusting your pace, or by rotating your position in the group since breaking trail requires twice the energy of hiking on packed snow), energy requirements are high. Moreover, keeping well fed is important psychologically, particularly when under a high level of stress or exertion. For a typical winter hike, the energy expended will amount to 2,000 to 3,000 food calories over what you normally eat. If you also sleep outside, you may burn another 1,000 calories maintaining your body temperature while you sleep. Added to a basal metabolic requirement of 1,500 to 2,000 calories per day, your total daily caloric intake should be 3,500 to 5,000 calories! For reference, a candy bar has about 250 calories and a half pound bag of M&Ms has only about 1,000 calories. When you stop, your requirements for extra calories decrease. You still need enough food and water to keep you warm, but you don't need nearly as many as when you exert yourself. If you find yourself getting cold during a break, eat a little bit, then exercise. Remember to put on extra clothing when you stop - food isn't all you need to stay warm! Don't worry about gaining weight, as you will in fact efficiently burn all of this energy. Think of it - you can pig out and not feel guilty. You need to eat a lot of food, and don't think you can get away without it either. Your body will feel it, and by going into energy debt you may be endangering yourself and other people on your trip. A winter hike is absolutely not the time to be on a diet. What Should I Eat? Planning your diet is very important. Eating that large an amount of food is tricky in practice (for some people, anyway). Moreover, some food takes a long time to digest, and won't help you while hiking. There are three major food categories to consider: Carbohydrates provide about 100 calories per ounce, on average, and can be digested quickly into blood sugar, which is immediately available to your muscles to burn. Thus, carbohydrates serve as the best source of readily available quick energy. Simple carbohydrates, which you will find in sweets and fruits, can be turned into blood sugar in minutes, and thus make great high energy trail food. Complex carbohydrates, like breads, take an hour or two to digest, and are good breakfast and lunch food to keep you loaded up with energy. Fats store up to 200 calories per ounce, but take longer (hours) to digest. They are metabolized differently than carbohydrates, and provide more long term endurance energy. Proteins provide 80 calories per ounce or less, take days to metabolize, and are never metabolized directly into blood sugars. Exercise doesn't increase your short term need for protein, although eating a balanced diet in general aids your general health and fitness. A diet of 50-60% carbohydrate, 25-35% fat and 15% protein is ideal for most active people. Importantly, you need an adequate intake of fats on the trail to properly metabolize carbohydrates, even though the fats will not give you the quick boost that carbohydrates do. If you rely strictly on carbos for quick energy, you may sugar crash: you wind up excessively boosting your blood sugar and then using it up very quickly. Symptoms include becoming sluggish and cold suddenly. You can rectify this by (you guessed it) eating some quick energy and drinking some water. However, you can best prevent sugar crashing by eating a sizable amount of fats with your carbos both before hiking and while on the trail - this helps even out your blood sugar levels during longer periods of physical exertion. Suggested Meals Breakfast is an important meal for active people: in studies, regular breakfast eaters show an increase in productivity and athletic performance. Suggested foods include:
Coffee and tea contain caffeine, a diuretic that contributes to dehydration, as discussed below. You should consider keeping coffee and tea to a minimum before a hike. Lunch as such usually doesn't happen on a winter hike. Instead, hikers nibble from breakfast to dinner and call it lunch. Sure, you can eat bits of a sandwich near midday if you like, but you're still not going to want to stop in the cold for too long.
Snacks are absolutely necessary. Don't stuff yourself at any one meal, but snack frequently throughout the day with:
Remember to repackage foods at home into single serving containers such as plastic bags. Remove as many extraneous wrappings as possible - it's hard to remove wrappers or open up containers at subfreezing temperatures with mittens on! Also be careful of foods that become inedible when frozen. The Importance of WaterDrinking ample amounts of water is one of the most important aspects of hiking:
When you exercise, particularly in cooler weather, the thirst mechanism becomes suppressed, and it often requires conscious effort to drink enough. On a typical day hike, you will lose four liters of water (about one gallon), more than you probably drink. Most hikers load up on water (and calories) before they head out, perhaps by drinking a liter of water with breakfast, and they hydrate again when they get done. You should still drink two to three liters of water during the day hike. A caution: don't drink too much water at once. You can not absorb it that fast, and it will go right through you. Along with water, your body also needs electrolytes. Your body fluids contain minerals such as sodium, potassium, calcium, and others, which are responsible for muscles contracting and nerves working. So called "sports drinks" help replace electrolytes, as do certain foods such as bananas. In the past, doctors recommended salt tablets to athletes, although today most doctors discourage using salt tablets. Unfortunately, in New England, you can't simply dip your cup into the nearest clear, running mountain stream and drink; most New England waterways have become contaminated with Giardia, a nasty bug, which causes extreme intestinal distress! Chapter 8 presents more about how to avoid getting giardiasis. You'll need to know this because you have to drink a lot of water to prevent dehydration. Preventing Dehydration Ask the leader of the trip how much water you expect to require on any leg of a trip. Besides your personal drinking water, there may be group needs for water, such as cooking. During the winter, you can melt snow for water. However, you still require enough water during the day to get you through the day's hiking. Also, snow may not be available at very low or very high elevations, or during the months of November through early January. Carrying water in the cold is tricky: you need to keep your water bottles insulated to prevent them from freezing (putting them in a thick sock or an insulated water bottle carrier works well), and keep them upside down (so the water will first freeze at the top, away from the lid). To keep your water bottle accessible (and thus help you drink enough!), you can carry a water bottle outside your pack in an insulated carrier, or keep a small pint bottle or wine skin inside your jacket on a strap around your neck. Wide mouth Nalgene type bottles are good because they are less likely to freeze closed, and they don't leak. A thermos filled with hot chocolate also adds a nice touch after an invigorating climb to a summit. Heed the following warnings: Caffeine suppresses both thirst and hunger sensations and causes your kidneys to remove water from your bloodstream faster than they normally would (i.e., caffeine is a diuretic). Not only are you dehydrating yourself by taking a diuretic, but you also are fooling your body into believing it is not hungry or thirsty. Caffeine comes in many of our favorite winter (and summer) drinks like coffee, tea, and hot chocolate (or any chocolate, for that matter). Alcohol also acts as a diuretic. In addition, it dilates the blood vessels of the skin, giving a false sense of warmth and affecting your thermal regulation and sweat control (to say nothing of its effect on your judgment!). Don't Eat Snow. Always melt snow before you consume it. Although you need to have water to metabolize and produce heat, the amount of energy you spend melting snow is greater than the amount of energy your body will gain in increased metabolism. © 1997 H-B Committee, Appalachian Mountain Club-Boston Chapter |