58

The calories to melt even frozen water are pretty small, and the water gained is certainly greater than that used to aid the use of those calories. http://en.wikipedia.org/wiki/Calorie So 1 calorie = 1 degree celcius (roughly with minor variation). Okay easy. Except it takes 80 times that to melt it initially. Screw snow, let's figure on ice cubes. 1 ...


47

All the advice I've seen emphasises melting snow before consuming to avoid lowering your core body temperature (rather than, specifically, risking dehydration). If possible, melt the snow using a stove, or alternatively, pack the snow into a waterproof container and keep it in a pocket or your sleeping bag until it melts. News stories such as this one, ...


36

First, you won't need to make this observation if you routinely drink when you stop to rest, and if you eat something at least slightly salty whenever you snack (if your snacks include jerky or salted nuts you're more than covered.) Second, pay attention to your thirst. Many of us ignore our bodies for hours at a time - postponing bodily functions during a ...


31

Liam's right that you can't/shouldn't overhydrate, but based on my experience it's easily possible to start the day under-hydrated. Maybe you're office-bound and don't drink enough water, or you've had a spot more alcohol the evening before than you should, or too much coffee... Either way, you start walking under-hydrated, and end up drinking more water ...


28

Dehydration occurs when there is more water going out or being used than is going in. Additionally, if you're drinking too fast (more than a litre an hour for an average adult male), you're not absorbing the water and so it doesn't count as going in. Confusingly, dehydration can also be classified loss of water, loss of electrolytes or loss of both. To add ...


22

In a survival situation without water you will die in days and without food you will die in weeks. So in general, there is no need to eat in a survival situation. That said, the quick burst of energy you can gain from eating a sugary snack could make all the difference. There is probably little harm eating a little after one day without water. Your body ...


18

As with any relatively unscientific field, there is a lot of lore out there that may have originally had a good scientific foundation, but the restrictions or specific conditions have long been forgotten and the answer takes on a life of its own out of context. The myth about eating snow seems to me to be one of these things. The main point is that it ...


18

If you run out half-way, perhaps you should bring twice as much? That being said... One option for day hikes is to hydrate well before hitting the trail. Also, have readily available water for your return. e.g. leave a water bottle in your car. An other option is refilling from natural water sources during the trip would allow you to consume an adequate ...


18

The symptoms of dehydration and over-hydration are similar, and this can lead to occasional mistreatment. Symptoms common to both include headaches, confusion, loss of appetite, irritability, nausea and vomiting, muscle weakness, muscle cramps, and seizures. With the popularity of sports drinks and staying hydrated, exercise-associated hyponatremia (EAH) ...


17

The usual advice to someone in an emergency situation in the wilderness is to stay put, so that it's easier for rescuers to find you. In this situation, performance isn't an issue. There is a folk belief that "thirst is too late," and that people are commonly dehydrated without knowing it. If you believed that, then you might drink some of your water even ...


16

Do a google search for urine colour (or color) chart and you will find many charts showing examples of what your urine should look like when you are hydrated. or not. Here is a slightly more humourous version but shows the principle:


16

The literature is mostly pro-drinking and anti-rationing. Hopefully these sources will provide some details for you. The U.S. Army survival manual does not recommend that you drink water only when thirsty, as this leads to under hydrating. Instead, water should be drunk at regular intervals. Even in cold weather: Don't take chances with hydration. Do ...


15

I think the problem is the generalization. It depends on the food. Watermelon is surely not comparable to trail mix. Also I have my doubts about the idea that berries are a problem and a mash to squeeze out the water is better than eating them because of the skins and seeds... that makes no sense. The way your intestine absorbs water is different through its ...


14

You'd be better of strength training your muscles to carry the extra weight of the water you need to carry. How much water an individual needs to stay hydrated is not a standard measure. Different individuals need more or less water to keep their bodies properly hydrated. I don't think it's necessarily wise to try and train your body to do with less of ...


14

I actually answered a similar question over on Pets not long ago... Warm weather walkies and water... however you've asked in a bit more detail so here goes... How can I know that the dog is perfectly hydrated? The dog will refuse water given to them if they feel like they've had enough to drink - this is a slim balance especially in male dogs, as it's a ...


13

There are a lot of myths about water and dehydration: Drinking Water for Hiking: Myths and Facts. One of these is the belief that people are in danger of being dehydrated without knowing it. Dehydration is a serious medical condition that sets in long after thirst, and thirst is a powerful sensation that commands your attention. When people say casually, "...


13

The absolute best way to figure out when to drink is by paying attention to your thirst. If you drink a cup of water when you aren't really thirsty, your body will start getting rid of excess fluid within a few minutes. But if you drink that same cup when you are seriously dehydrated, you won't pee it out because your body won't have excessive moisture. ...


12

There are two types of water-based concerns while doing strenuous activity in the desert: dehydration and hyponatremia. Dehydration occurs when your body is not getting enough water, and is the most common. Symptoms include irritability, headache, lack of energy, bright yellow/orange and infrequent urine. You lose water while you sweat, but in hot climates ...


11

Colour if urine is a good indicator. The lighter the colour, the better your hydration is. Once you start to feel thirsty, you are already dehydrated.


11

You have not provided any evidence you were actually dehydrated; it seems you only tought you were dehydrated - I assume you had dry mouth and felt thirsty. Symptoms and signs of dehydration are described here in great detail: Dehydration Symptoms and Signs. In short: thirst, dry mouth, fatigue, headache, nausea, decreased skin elasticity, dark urine, ...


11

How much water you need depends on how big you are, how fit you are, where you are and what you're doing. For example, on Mount Everest, the average person needs to drink 4-5L of water each day just so that their body can function properly. You lose water through your breath, perspiration, urine and bowel movements. If you're a big guy that's out of shape, ...


10

If you can, melt it beforehand - not because of dehydration but because of the obvious; it'll cause you to get rather cold rather quickly! If you can't and it really is an emergency (the only time I'd suggest it might be worth considering) then I haven't found a general consensus on whether it's a good idea, probably because it comes very much down to ...


10

Maybe not a real way to get water inside your body, but what helps with me is chew on chewing gum. It distracts from the feeling I'm thirsty or drinking too much water without really needing it. Also chewing gum is very light to take with you. Of course the gum is not a substitute for water which is needed anyway.


10

This seems a bit low to me, but there are lots of other factors to consider. The main ones are temperature and exertion/walking speed. Different people also definitely need different amounts of water. One of my friends was nicknamed desert-man as he drank approximately 4x as much as everyone else. If you are in the UK or a similarly cool climate, then 100ml ...


10

Dehydration in dogs is very similar to dehydration in humans. This link should give you an in depth answer. My main points are these: If the dog has a dry nose, dry gums and/or dry mouth it most likely needs water. Excessive panting is another big sign to look for seeing as that's how dogs regulate their body temperature. You should treat their dehydration ...


10

While various sources suggest drinking some blood in emergency will help, the risks outweigh the benefits. From 5 Myths of Dehydration: Sure, there’s water in blood. But whose or what’s blood are you planning to drink? Some of the traditional cattle cultures of Africa still consume cattle blood, often blended with milk. But this is done for protein and ...


10

You basically have it, the formula is Your Weight at start - Your Weight at end + Weight of water consumed - Weight of water urinated --------------------------- = Water lost via sweat Then you divide the water lost via sweat by the amount of time to find your sweat rate. Water lost via sweat/time spent exercising = sweat rate. Of course, this will ...


9

You really don't need equipment as such. There are quite a few symptoms that you can observe, may be at a gradual rising rate. Symptoms are observed with as the degree of Dehydration gets worst. Normal: (I'll say recoverable without having to stop the venture then and there itself. One can continue only if he/she can start hydrating himself/herself from ...


9

I am assuming that, as you moved out of the snow field you were also descending, therefore, I think it is more likely you were experiencing altitude sickness and your symptoms reversed as you descended. The presence/absence of snow was purely coincidental. Dehydration contributes to altitude sickness through, lower air density which increases respiration ...


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