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Hydration: 1.5 Quarts of Water When Backpacking on the Trail.

How much water should I drink when backpacking?

This is a loaded question with no single answer…so, I decided to look this up to get a better understanding of hydration, why we hydrate, and how much water I need during my hikes and backpack trips. Here is what I found.

How much water should you drink when backpacking? It is recommended by a number of sources to drink up to 1 1/2 quarts of water per hour for every hour you are out on the trail.

Hydrating before, during, and after exercise is very important in maintaining the body’s ability to regulate our temperature. I.e. cool yourself off in the hot summer and warm you up in the winter.

hydration: it is important to stay hydrated on the hike...unsure if this is the right choice.

However, this seems like a wide span of fluid intake. Clearly, many variables have to be taken into consideration when it comes to YOUR exact needs during a long hike or backpack trip and caution should be taken when thinking about drinking from bodies of water. But first, let’s talk about why we have to hydrate in the first place.

Why do I need to drink water in the first place?

It is a well-known fact that our bodies are made up of nearly 60% water. Therefore, to keep proper balance, we need to replenish what we lost through activity. Our bodies are very complex, every day we require water and electrolytes to perform tasks most efficiently. Water helps in several ways.

Why backpackers need to worry about hydration.

To Regulate our Core Temperature

To regulate our core temperature: so, if it is hot, we need to reduce our temperature and if it is cold we need to increase our temperature. That is why hydration plays a large role in how we feel temperature-wise on our hikes. However, many variables are considered for optimal thermoregulation. We will discuss that in the next section.

To Maintain the Health of Our Heart, Brain, and Muscles

  • When we are dehydrated it puts a strain on our hearts. Our heart rate can elevate causing stress to the heart. Moderate to severe dehydration has been also known to cause heart attacks in some cases.
  • Our brains require a delicate balance of fluids to not get confused, agitated, or lightheaded. When you backpack you want to be on alert and ready.
  • And our muscles require the proper fluid balance as well as electrolytes to perform up to their most efficient potential. Dehydration can lead to sluggishness, weakness, and difficulty maintaining balance on your longer more strenuous hikes.

To Lubricate Our Joints

When we hike up and down mountains and along a riverbed, our joints get some pounding. For example, the synovial fluid in our knee joints takes up as much as 80% fluid. This means that if you are dehydrated that percent decreases and puts undue strain on your knee joints.

To Transport Nutrients to the Cells

Our cells require loads of energy to perform at their best. For that reason, staying hydrated helps the cells get the needed nutrients throughout the hike.

To Remove Waste From Your Body

As we hike, our bodies use our food and fat as energy. Therefore, the end products of the metabolism for energy are waste products. Because of that, hydration plays a large role in removing waste through perspiration and the GI tract.

To Flush Metabolized Fat From the Body

Depending on how aggressively you hike, fat is being utilized for energy in varying degrees. Generally, if you are cruising along at a relatively low pace fat to carbohydrate ratio is about 50/50. The end product of fat gets removed from the body primarily through sweat and urine. Meaning, when we are dehydrated this system can’t perform as well.

People who hike in a fasted state, yes some people do, must be extra careful about electrolyte balance and proper hydration. The reason for this is that they aren’t getting electrolytes or water from the foods they eat.

Several other functions require proper hydration but we will leave that to the medical community. The bottom line is, that to stay hydrated there are many variables to consider.  

Hydration variables that you need to consider while backpacking:

I just finished a small hike near my home. It was about 75 degrees out but wicked humid (that’s what we say in the Northeast). While I was only out for about 3 hours, I felt dehydrated and a little overheated even though I drank about 2 or 3 quarts of water. This is what I usually expect to drink at this temperature. However, I failed to take humidity into account.

hot and humidity takes its toll on body temperature when hiking. Staying hydrated helps cool us off.
  • The temperature and humidity on the hike: hot and humid verse hot and dry are two major contributors to dehydration for different reasons which we will point out later in the article.
  • Your personal sweat rate: are you a heavy sweater, light sweater, salty sweater. It has been found that people with more body fat tend to have more difficulty regulating body temperature due to the increased metabolic heat load compared to the size of the surface area to dissipate heat.
  • What physical shape you are in: a person who is in great hiking shape tends to sweat less on exertion than someone just starting out. Therefore, the out of shape person will sweat more and require more water to regulate their heat.
  • Men sweat more than women: The US Military has studied sweat rate during exercise for a long time. They have found that men sweat more than women but have the same physiological response as men.
  • Altitude increases the change of dehydration: Hiking at altitude requires 1 to 1 ½ liters (quarts) of additional water for the lungs to hydrate the air and to help prevent altitude sickness according to the Altitude Medicine.org located in Telluride Colorado.

Does humidity effect hydration and how much water we need when hiking?  

As we already mentioned, we drink water to regulate our body temperature. In order to do so our body sweats which in turn evaporates. When water evaporates off our body, we experience what is called evaporative cooling. Evaporative cooling happens when water turns from a liquid to a gas with a resultant drop in temperature. But what does this all mean when it comes to humidity.

During a humid day, your sweat comes to the skin surface and just sits there. Because of the high level of water in the air, water on your body doesn’t easily evaporate into the air. Therefore, any cooling that you would experience is minimized in humid weather.

How much water should I carry to prevent dehydration?

When I first started hiking we carried metal canteens. Today, hydration packs help you transport large amounts of water easily. How much is enough?

According to a study performed by the National Center for Biotechnology Information, there are general rules to follow to remain hydrated. As a result of some digging, we have found that more water is required in the following situations.

  • In mountainous or desert terrain
  • Extreme hot, cold, or humid temperatures
  • Personal sweat rates, general thirstiness, and obesity cause an increased need for fluid.
Proper hydration: Drinking water even when it is cold out

Recent Hydration Studies

Pre-Hydration Study

The American College of Sports Medicine stated that pre-hydration should begin with 14 to 20 ounces of water 2 hours before your activity. Electrolytes should be replaced as they are lost during sweating; they include sodium, chloride, potassium, magnesium, and calcium.

According to a study by the US military by Dr. Gisolfi finds that water “requirements during exercise in the heat depend on fluid loss from sweating. The sweat rate is proportional to metabolic rate and can amount to 3 to 4 liters per hour or as much as 10 liters per day.

When trained, “heat acclimatization can increase sweat rate by 10 to 20 percent”. Meaning, the more in shape you are the better you thermoregulate your core temperature through sweating.

“Men sweat more than women and require more water, but women show the same physiological responses as men when performing work at the same relative intensity. Well-trained heat-acclimatized women show similar physiological responses to hot-wet and hot-dry heat as men.”

The study also points out that there is “no decrement in sweating as we age”, meaning that we require the same amount of water during exercise.

Do overweight people require more water when backpacking?

While we can’t control the weather, temperature, and terrain, we can, however, control our level of fitness and weight. In the same study by Dr. Gisolfi note above. He found that the heavier and more out of shape a person is, the more water one should drink.

The study found that overweight and out of shape people have “more trouble dissipating heat when exposed to a warm environment exercising at the same intensity as an individual who is not carrying that much weight.”

It was found that overweight people generate more heat but don’t have the surface area to dissipate that heat. Therefore, their core temperature goes up.

What are the signs of dehydration?

As we only can provide generalities as to how much one should drink, we do know the signs of not getting enough water resulting in dehydration.

According to WebMD, the following are signs of dehydration: dry skin, increased heart rate, increased breathing, sleepiness, lack of energy, confusion, fainting, irritability, dark urine, dizzy (WebMD).

Altitude and dehydration

The Institute for Altitude Medicine in Telluride Colorado points out that water requirements increase up to 1 ½ liters per hour when at altitude. They note that “staying hydrated is important at altitude. Symptoms of dehydration are similar to Altitude Mountain Sickness.

Altitude Medicine also noted that “as you hike you also lose electrolytes so you will need to replace those as you go too.” They recommend Himalayan Sea Salt as a great replacement for electrolytes. It can be added to water and into foods that you eat throughout the day.

proper hydration in extreme cold and altitude.

A closer look at Himalayan Sea Salt reveals that it carries many electrolytes and necessary minerals. The most important for electrolyte balance include sodium, chloride, calcium, magnesium, and potassium.

What is recommended to stay hydrated?

For proper hydration, you need lots of fluid balanced with electrolytes. Water is easy, but to get enough electrolytes using sea salt, coconut water, lemons, green vegetables, bananas, and even trying a sugar-free electrolyte drink. I first heard of ketorade from Dr. Ken Berry. Dr. Berry promotes a keto lifestyle and has developed what he refers to as ketorade. So, if you feel you are low in electrolytes here is a link to his ketorade video here.

Or watch the video below:

So, what is the bottom line?

The bottom line is to drink 1 to 1 ½ liters/quarts of water per hour while ingesting electrolytes through your food and drink. For example, try ketorade for a quick and thirst-quenching electrolyte boost. Also, there are a number of electrolyte tablets, like Nuun for example.

And remember it is not just about water and electrolytes but also temperature, terrain, fitness level, and gender. Have fun on your next hike and remember to stay hydrated!

Sample Hydration Packs:

Camelbak Hydration Bladder

Camelbak was my first hydration pack. I still use hydration packs and seldom carry water bottles on day mountain hikes. Check out Camelbak models here.

Related Questions:

How Much Does Water Weigh?

How much does water weigh? For instance, one gallon of water weighs 8.34 pounds or 3.78 kilograms. For example, carrying 64 ounces of water weighs just over 4 pounds-which can be more than your tent and backpack together. 

Are Backpacking Water Filters Safe?

The short answer is YES. Because water filtration devices and purifiers remove the protozoan spores like Giardia and Cryptosporidium, bacteria, and viruses from water that you take from the stream or lake while backpacking. 

If you want more information about water filters and purifiers, check out our post: Are Backpacking Water Filters Safe?

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