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You Might Not Be Drinking Enough Water When You Hike

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You Might Not Be Drinking Enough Water When You Hike

Jun 16, 2021

In Utah’s dry climate, you might not notice how much water you’re losing through sweat. Even for short, hour-long hikes, dehydration can set in faster than you realize, which can lead to serious complications like heat stroke and exhaustion. Dr. Emily Harold, sports medicine specialist at the University of Utah Orthopedics Center, talks about how much water you should be drinking on the trail, as well as tips to make sure you stay healthy and hydrated while enjoying the outdoors.

Episode Transcript

Interviewer: Coming up next we're going to talk about a common hiking hazard and how to make sure it doesn't happen to you. That's next on The Scope.

I want you to think about it. When you go hiking, what problems do you normally run into? Maybe sore feet, tired legs, blisters. Pretty common problems, but today Dr. Emily Harold, a sports medicine specialist at University of Utah Orthopedic Clinic, is here to tell us about one of the more common hiking problems that isn't something that a lot of people really think about, and that's dehydration. And when I heard about this I'm like, "Really? Dehydration? Don't we all drink enough water? It seems like everybody's got a bottle of water."

Sweating Can Cause Dehydration

Dr. Harold: Well, I think we all drink some water. I think that we don't all drink enough water. I mean, I think that we are blessed to live in a great state that has an amazing climate, and it's a very low humidity climate. And because it's a low humidity climate, when you're outside and it's hot outside and the sun's beating down, a lot of times your sweat dries quicker and you don't really realize how much you're sweating. And it can almost be pleasant when it's 80 degrees outside in this environment versus 80 degrees in Houston, Texas, in which case everybody knows they're sweating.

And so a lot of times people are sweating more than they realize and they're losing more water than they realize and they don't replenish enough, and that can lead to headaches, and tiredness, and in extreme forms can even lead to things like heat exhaustion, heatstroke, which can cause a lot of damage over time.

Interviewer: So if I was just going out for like an hour or two hike, do I really need to take water? Is that enough time to start getting symptoms of dehydration?

How Quickly Does Dehydration Set in?

Dr. Harold: It's enough time. We would recommend at least a quart an hour. So if you're going to go out for a two-hour hike, one, we recommend probably drinking a liter before you go. And then while you're out, at least a quart an hour while you're out. More if you are running, trail running, doing activities that are more than just walking.

Interviewer: You've covered more endurance-based events like marathons and whatnot, and you say that it can really be common in those events. Explain that a little bit.

Marathons & Hot Weather

Dr. Harold: It's a common problem. A lot of times in marathons, people are out on the course for four, five, six hours. On a hot day, they don't drink enough fluid when they're out running and a lot of times when they come in after they cross the finish line, they can have some dangerously high body temperatures, 103, 104, 105. And so we really kind of institute a rapid cooling part and we try to give IV fluids for hydration, but it's very important that you drink enough water, especially when the temperature gets up above 70.

Interviewer: And when that sun's out, is it even worse?

Dr. Harold: Yeah, because the sun dries the sweat off a little quicker, and so you don't get the same cooling effect as you get when it's a little cloudier.

Benefits of Salt 

Interviewer: So drinking water, very easily preventable of dehydration. What about extra salt in those situations?

Dr. Harold: It is recommended that if you're out for more than an hour that you do ingest some salt.

Interviewer: Really? And above and beyond what I would normally get in my diet?

Dr. Harold: I think that's why trail mix became so popular. Because people realized if they went walking for a long time, that salt that comes from peanuts and that kind of thing can actually help to retain some of that water that you're drinking, and that helps to replenish their water stores a little easier.

Interviewer: Gotcha. And then also we're talking about kids. If you go out hiking for a couple hours with kids, that has a different effect on a kid than it might an adult.

Keeping Kids Hydrated

Dr. Harold: Exactly, and if you're like my kids, you like to run ahead and you're constantly exploring. So you're not drinking water and no matter how much you tell them to drink water, by they time they're to start drinking when they're thirsty, they've already gotten a little bit dehydrated. So it gets really important just to watch your kids' water bottles. I usually recommend bringing a water bottle for each kid and having them drink from it, so you can monitor how much they're consuming.

And if you get somewhere and you realize they haven't really drunk very much water at all, then you can push their fluids a little bit just to keep them from getting dehydrated.

Heat Exhaustion & Heatstroke

Interviewer: How often does heat exhaustion and heatstroke really lead to things? I mean is that not too common, more common than I might think?

Dr. Harold: I think both. I think we'll see a lot of hyperthermia or high temperatures sometimes in the emergency room. Usually if you catch them early and you cool people quickly, it doesn't lead to bad outcomes. Now if you have someone who is in Canyonlands or Moab and gets lost and wanders, that's something that can lead to heatstroke and it can lead to some, exactly, brain injury.

Interviewer: Just kind of wrap up, then, for myself or for my kids, what would I look for for symptoms to indicate they need to be drinking more water? Or is it just monitor water drinking?

Dr. Harold: I think it's easy enough to monitor water drinking. A lot of the symptoms are kind of difficult. Things like fatigue, they get that when they hike anyway. Headache is a common one. So if your child or you notice that you are starting to get a headache when you're walking, a lot of times that's because you're dehydrated. So that's the earliest one.

Know When to Take a Break

Interviewer: So in that instance drink water, get out of the sun for a little bit, rest for how long?

Dr. Harold: Exactly. Find a shady spot.

Interviewer: How long would you want to rest for?

Dr. Harold: Some people find a shady spot, drink some water, you want to rest for probably a good 10, 15 minutes until you start to feel better.

Interviewer: Yeah, and that will start to go away. And then you're fine to go back out again?

Dr. Harold: Absolutely.

Interviewer: I mean, this seems just like one of those topics that I don't think a lot of people think about and a lot of people don't think is really all that serious in their life.

Dr. Harold: Yeah, I think that's my final thought. It's something that I know I could do better at and most of us can do a better job of hydrating, but it is something that can lead to problems and it does make for a much more comfortable walk if you're properly hydrated.

updated: June 16, 2021
originally published: August 24, 2016