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The Hype of Dehydration and Heatstroke


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  • #1974960
    Dan @ Durston Gear
    BPL Member

    @dandydan

    Locale: Canadian Rockies

    Scary stuff indeed. My heart was fast but not erratic – so steady but alarmingly high while I laid there for hours. My guess was 120 BPM whereas I normally measure 55-65 at rest.

    #1974965
    Bob Gross
    BPL Member

    @b-g-2-2

    Locale: Silicon Valley

    Many years ago I was leading a peak climb on skis. The group got up to the midway camping point during the first day, and the plan was to bag the summit early on the second day. That first evening we were sitting around eating dinner, and then we retired early to sleep before the 4 a.m. wakeup call. Late that night one of the crew came over to my tent to wake me up. His tentmate was having some sort of stress and could not sleep. I checked the guy out, and he had a fast pulse. His respiration was not shallow and rapid (which might point to hyperventilation), but in fact it was deep and rapid, and he had plenty of oxygen. There was not a great deal that I could do for him, so I gave him one pill, had him drink some water, and then try to sleep. That worked. At 4 a.m., the rest of us got up to prepare for the summit, and this guy decided to stay in camp, even though he felt better. We all left the mountain by the afternoon of the second day.

    What was the pill? A salt tablet, perhaps as a placebo.

    What was the ailment? Hard to say. Maybe an anxiety attack. Maybe dehydration. Maybe low electrolytes.

    –B.G.–

    #1975025
    Paul McLaughlin
    BPL Member

    @paul-1

    Dan, I can't diagnose what happened to you, but I can safely say that if I had done what you did while eating and drinking as you describe I would have felt like crap at best. Saltier food and more water would be my recipe for a better result – it's what I have done in the past in similar situations. Walking across the Grand Canyon in a day in midsummer, I drank all the water I could get(around 3 or 4 gallons) and ate a lot of salty peanuts. That worked out well. My feet were trashed by the end, but no ill effects from the extreme heat (110 at the river) and low humidity.

    #1975031
    Roger Caffin
    BPL Member

    @rcaffin

    Locale: Wollemi & Kosciusko NPs, Europe

    Hi Dan

    > some insight/diagnosis on my situation last August.
    I am NOT a medico, but …

    To me that sounds a bit like a combination of heat stress (not heat stroke) and a viral infection. I suspect that without the virus you might not have been affected at all.

    Cheers

    #1975036
    Nick Gatel
    BPL Member

    @ngatel

    Locale: Southern California

    A highly trained endurance athlete is a lot different than us mere mortal backpackers.

    I agree that we focus too much on drinking water and to never, never feel the least bit thirsty.

    Each individual is much, much different. A while back Craig and I did an all day hike through the desert. I consumed probably 1/2 the water he did and probably was less thirsty. At the time Craig was doing a lot of long distance running training and I am about 30 years older than him. My body just works differently, not to mention I am more attuned to water needs since I hike in deserts a lot. In addition Craig is bigger than me with lot more muscle. Neither of us were in any kind of danger or was water a problem, just want to point out that each body is different.

    I normally stop to drink about once an hour, and sometimes longer between stops… even when it is hot. But I have a lot of experience hiking were water is a precious commodity and am acclimated to the conditions — if there is such a thing a acclimation.

    The other thing to consider is the ambient temperature. Anyone running a 5K in 90F temps is going to have a different experience than running it at 100F.

    I remember Colin Fletcher posting a table showing how long a person could last with different amounts of water. At 120F during the day and only walking at night, the average person will die in 1 day with no water, 2 days with a quart of water. If they sat in the shade at 120F and did nothing to exert themselves, the average person will die in 2 days. Move the ambient temperature down to 70F and death occurs in 10 days for no movement and 7.5 days if hiking at night.

    Almost every year people die from "heat stroke" where I live when it gets hot. Most of these die on day hikes on strenuous trails. Of course we don't know about any pre-existing conditions or their physical condition. There have been several Marines from the 29 Palms Marine base, where they do desert training, who have had to be rescued on the Skyline Trail here, when they have hiked less than 7 miles and ran out of water and became too ill to continue.

    I guess the bottom line is that we need to know what the hell we are doing when hiking. Articles like this a good, but we need to be prepared.

    #1975089
    jscott
    BPL Member

    @book

    Locale: Northern California

    Elevated heart rates will often revert to normal rhythm on their own. You really want this to happen. But think this through: someone like Dan, obviously young and fit, crashed his body to a point where his heart went crazy for many hours. This is a warning sign. If it happens to you, and your normal rhythm returns, you might want to take it easy for a couple of days.

    Look, Dan's "one night sixty miler" without a hat in high temperatures and not enough water: that's extreme. This would be extreme–in my estimation– even with the hat and water etc. I mean, I couldn't do it. Sometimes everything works right and you get away with pushing the envelope. But if you watch (or play) enough basketball, for example, you realize that the human body has peaks and valleys. Performance varies. Everyone on this forum has bonked for no apparent reason, etc. And you can't always predict things beforehand.

    Sometimes mental determination overrides the body's needs and messages.

    I used to think that I couldn't exert myself too hard; it was always healthy to push the limits. I'm backing off on that philosophy. But then I'm becoming an old guy.

    p.s. they did instantly put me on fluids in the e.r. and say that I was dehydrated.

    #1975137
    Larry De La Briandais
    BPL Member

    @hitech

    Locale: SF Bay Area

    I always thought that the link was when you became dehydrated enough to stop sweating your temperature began to rise. If it got high enough then you could suffer heat stroke. Anyone know? And anyone know what heat stroke actually is?

    #1975144
    Bob Gross
    BPL Member

    @b-g-2-2

    Locale: Silicon Valley

    Generally there is a maximum body temperature, maybe 106 F, and that is where irreversible brain damage occurs. Maybe it will be a little. Maybe a lot.

    –B.G.–

    #1975156
    Michael Ray
    BPL Member

    @topshot

    Locale: Midwest

    I wish the author explained more of what they found in the runner that kept gaining heat in the ice bath.

    Fascinating subject since my son and I will be doing Grand Canyon and a little Death valley this summer. I don't recall noticing my sweating in dry desert heat though I suspect it's just because it evaporates so fast and the air temp negates the evaporative cooling effect. That was decades ago so maybe I don't recall correctly. I do remember having the windows down while driving felt like standing in front of a furnace duct. :)

    #1975162
    Ian
    BPL Member

    @10-7

    Dan,

    Without being there to take your vitals over a period of time, and BP checks supine and standing, all I can offer is pure speculation…. And I'm not a Dr.

    My first guess is hypovolemic shock exacerbated by hyponatremia/kalemia.

    Second guess is SVT.

    Third guess, all of the above.

    #1975163
    Gregory Allen
    BPL Member

    @gallen1119

    Locale: Golden, CO

    I'm reading Noakes book now and it is slow going with lots of detail and references. It is a VERY well documented and referenced book. I think the key is drinking when thirsty and not forcing water, or a "sports drink", past that point. It is very clear that ultra endurance athletes are much different than us mere mortal BPL-ers, but how much different I don't know…maybe not as much as we think. We do respond in a similar fashion to water loss, but the human body is well equipped to handle that water loss, elevated HR, and even some moderate elevated body core temperature and recover without untoward effects. Metabolic rate, or level of exertion, seems to be the key and not what has been hammered into our heads about hydration, electrolytes, etc over the last 30-40 years, is the key. The body will adjust itself with a fairly wide margin of safety. Even ER docs have been duped my the pseudoscience propagated by the market gurus on the payrolls of the sports drink and supplement companies. Pushing too far past what our bodies tell us is dangerous, but maybe not as dangerous as what we have been led to believe marketing and industry. Moderation, and doing what your body tells you, is key. Slow down when it tells you to slow down, and drink when it tells you rhat you are thirsty. Keeping it fueled with balanced nutrition is far more critical that some "cocktail" of electrolytes or excessive water.

    #1975177
    Lynn Tramper
    Member

    @retropump

    Locale: The Antipodes of La Coruna

    Though I don't doubt the hype of heatstroke caused by dehydration, for me, even mild dehydration can cause a migraine. I am not alone in this. So I drink regularly, before I am actually thirsty, to prevent migraines. My migraine-free comfort has improved immeasurably since I have been using a hydration bladder instead of waiting until I stop to access a stream or bottle on my pack. We are all different!

    #1975195
    Anonymous
    Inactive

    Dan, i'm not a doctor, nor professionally trained anything medical, but i have had a long time interest and research in diet, natural health, etc. because i was forced to treat myself due to a mysterious childhood condition. Necessity is the mother of invention, AND applied knowledge.

    It sounds like possibly one contributing factor was you were consuming too much protein on too hot of days. The combination of energy bars, jerky, and tuna equals a lot of protein (depending on the energy bars, some seem to have a lot and others not so much). Protein requires a lot of water to digest, hence it can speed up and/or exacerbate dehydration.

    Not only that, because it tends to be harder to digest in general, it generally raises your metabolism making you feel hotter, hence you will sweat more, internal temps may more easily become critical, etc. Plenty of trained, knowledgeable people have advised to limit your protein while very active on hot days and stick more to carbs. Save the proteins for when it's cooled down and you're more inactive.

    Anyways, there may be more contributing factors than that which helped to create a perfect storm of body imbalance.

    #1975248
    Dan @ Durston Gear
    BPL Member

    @dandydan

    Locale: Canadian Rockies

    I didn't actually eat the tuna – I just drank the liquid brine to get some salts into me. My jerky was pretty minimal too – not more than 2oz. I'm not sure how much protein was in the energy bars.

    #1975258
    Rob E
    Spectator

    @eatsleepfish

    Locale: Canada

    Dan,

    I'm no doctor, nutritionist, or anything like that, just my own experience with endurance sports, but here is my take: I would suspect a combination of dehydration, electrolyte imbalance, and not enough calories getting digested properly (note, not eaten, but digested and absorbed). I've had almost identical symptoms quite a few times in the past. The last time I experienced it was a few years ago training in the heat for an ironman distance triathlon. For me the trigger is some dehydration, plus the wrong combination of foods, then trying to push through it basically shutting my body down eventually: bad headache, nausea, overheating, waves of chills, cold sweats, elevated heart rate, inability to sleep.

    To cover that distance in those conditions, the speed, trail time required with the heat, you have strayed from the hiking to an intensity that would be an endurance sport. Hang around the finish line at any all-day endurance event and you'll see a lot of similar symptoms to what you describe. At higher intensities, a little bit of dehydration, or the wrong combination of foods shuts down their digestive system, they can keep eating, but things aren't getting digested, glycogen stores get burned up, blood sugar drops, dehydration kicks in and the results can be nasty.

    Endurance sport forums have many posts from people who are very physically fit and well trained, but are wondering what the heck happened to them when they pushed themselves further/farther/faster in tough conditions and they basically shut down. The lesson on those forums is that muscular endurance and fitness is only one aspect of the training, and that nutrition is critically important and is an aspect of endurance sports that must be trained and dialed in as well. Basically everyone has to experiment in exerting themselves all day in tough conditions and find the right combination of foods and fluids that works for them. I know this forum can think of gatorade, gels and other sports nutrition as simply marketing hype, but in tough conditions at higher intensities, the stuff really works well, at least for me, but it took over a year to fully dial in my nutrition plan to find the combination products, intake rates and timing that really worked for me.

    I will say though, pretty impressive mileage in tough conditions to gut it out like that.

    #1975277
    Larry De La Briandais
    BPL Member

    @hitech

    Locale: SF Bay Area

    I always get a headache when I get dehydrated. It took me a long time to realize that was the cause as I "blamed" it on everything else first.

    #1975284
    John S.
    BPL Member

    @jshann

    Dan Durston had heat cramps that phased into classic heat exhaustion in my opinion, brought on by everything ; ) (environmental exposure, dehydration, electrolyte imbalance).

    #1975304
    Anonymous
    Inactive

    My bad, i assumed after you drank the tuna brine, you then ate it at some point during that difficult period and yes 2 oz of jerky isn't much all in all. In any case, to simplify it, i agree with what John Shannon wrote, as i suspect there were multiple factors. Keep the protein thing in mind though for the future, though that may not have been a big factor in this particular case. I have largely stopped eating any foods higher in protein while being very active on warmer or hot days, and i've noticed a bit of a difference in how much water i will need, how much i sweat, how hot i feel, etc. Btw, Cody Lundin is one of the people who talks about this in one of his books, and as he is a desert survivalist par excellence, he should know what he is talking about.

    Conversely, i do the opposite when it's very cold and/or i'm less active on cooler days. I will eat more protein and fat, and definitely notice a difference in being warmer and more comfortable then. I saw some idiot on a reality, comedic t.v. show once, decide to eat only meats for a period, and he ended up being tired all the time, got the "meat sweats" bigtime and generally ran hotter than usual.

    #1975328
    Dan @ Durston Gear
    BPL Member

    @dandydan

    Locale: Canadian Rockies

    Thanks for the thoughts guys. Since then I've been paying more attention to electrolytes (i.e. adding some powder to my water). That also makes the water taste better which helps with hydration.
    sweat

    #1975330
    Nick Gatel
    BPL Member

    @ngatel

    Locale: Southern California

    Dan,

    The white residue is very familiar. In my mind our food should contain most of what we need. For me, eating a few Pringles during the day does the trick. I really don't care for sports drinks — plus if you fill all your water bottles with sport drinks, how do you wash your hands after pooping; don't ask how I know to ask this question :)

    Electrolyte replacement is a different animal for those engaged in extreme sports.

    #1975398
    Sarah Kirkconnell
    BPL Member

    @sarbar

    Locale: Homesteading On An Island In The PNW

    Lynn,

    I too get migraines from dehydration. Walking while having auras blows so I have learned the painful lesson to stay ahead.

    As for the whole heat stroke topic…well all I can say is one of my past hiking partners lost his wife to a combination of it. It came on quick. Anytime other issues crop up – having vomiting or diarrhea for example, while hiking in heat/exposed, heat stroke can easily grab a foot hold. And it can be fatal quickly. It isn't something to take lightly IMO.

    #1975451
    Anonymous
    Inactive

    "plus if you fill all your water bottles with sport drinks, how do you wash your hands after pooping;"

    Purell.


    @Dan
    Wise move, deciding to add electrolytes to your water. Don't let anyone convince you otherwise at the levels you are exercising. That picture of your pack strap says it all. Been there done that, and I'm here to tell you electrolytes have changed my life. It doesn't have to be a fancy sports drink or ripoff Nuun tablets, a 1/4 teaspoon of Mortons Lite salt/liter of H2O will suffice. It provides ~280 mg of Na and ~350 mg of K, which are the two electrolytes most easily depleted. You may want to cut your water with something like Crystal Lite if you don't care for the taste of slightly salty water. A small canister of Mortons Lite costs something like $2.50 and will last at least a year, probably more, depending on how much hiking you do and the conditions you are hiking in.

    #1975455
    Bob Gross
    BPL Member

    @b-g-2-2

    Locale: Silicon Valley

    "It provides ~280 mg of Na and ~350 mg of K, which are the two electrolytes most easily depleted."

    I wish they would sneak a little magnesium in there.

    –B.G.–

    #1975456
    Jason Elsworth
    Spectator

    @jephoto

    Locale: New Zealand

    Born into a Catalan family, Jornet [Kilian] grew up in the Spanish Pyrenees at 6,500 feet, and his gifts are literally in his blood. “When you are born and bred at altitude, you tend to have a higher blood volume and red-cell count for oxygen-carrying capacity,” which translates to better endurance, says Stacy Sims, a researcher at Stanford who holds a doctorate in exercise physiology and nutrition science. Years of daily running and skiing up mountains have further bolstered this advantage. This helps explain why Jornet sweats so little. During exercise, the bodies of very fit people quickly act to disperse heat by, among other things, vasodilation — expanding blood vessels at the skin’s surface where the air can cool the body. A body that sweats less loses less precious liquid from its circulatory system, a major factor in fatigue.
    In moderate temperatures, Jornet says, he can run easily for eight hours without drinking water.

    From -http://www.nytimes.com/2013/03/24/magazine/creating-the-all-terrain-human.html?pagewanted=all&_r=0

    I add salt to my water and have to be very careful to stay hydrated due to a health issue.

    #1975461
    Nick Gatel
    BPL Member

    @ngatel

    Locale: Southern California

    "Purell"

    Hmm… is it a good idea to kill the good germs with alcohol? Might it get rid of the germs that protect us? Does soap and water do a better job of cleaning?

    Inquiring minds want to know.

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