Water alone won't keep you well hydrated, will it?

[cliffdiver]

dc4bs once bubbled...


A small part of this may be because when you introduce a blob of very cold water/drink into your stomach, your body then has to "warm it up"... This burns up energy/resources better spent keeping you cool and the end result is a higer core temp, not lower.

By drinking "room temperature" liquids, you don't create that temperature imbalance your body then has to deal with.

Either way, your body gets the liquid needed to produce more sweat to cool you off so cold water is still much better than no water.

It's kinda like in school in late spring when the teacher tells everyone not to fan themselves. The energy spent waving a folded piece of paper to cool your face creates more body heat than the cooling you get from the fan... But it does feel nice in the short term...

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EDIT/ADDITION: It's better to drink cold liquids (if you have to) in small amounts over time rather than chug it all at once to help reduce the shock to the bodies natural temperature regulating systems.

Okay, uh, but not really. Your body doesn't really have any system with which it detects cold liquids directly and heats them up so you can absorb them. Your body doesn't spend any extra energy/calories heating up the liquids. By the time your large gulp goes through the throat, down the esophagus and spends a moment or two in the stomach, it's very rapidly heated up. These are very hot passageways and caverns (stomach) and heat is quickly transfered to the drink. It has even more time to heat up if there is any "solid" food in your stomach. It is true that your body, already plenty warm (not fighting to keep so, that is, you're not facing imminent hypothermia) that your body's got heat to spare, and it simply takes it and passively transfers some to the relatively tiny amount of liquid you just injested. You'd have to overwhelm your system with an uncomfortably large (read: you get sick and perhaps "brain freeze" before this happens) quantity of ice water to cool you down enough that your body says, "okay heater, kick in!" Don't forget, it's almost 100 degrees F in there, even when you feel chilled.

True, though, that you want to consume over time, rather than massive gulps followed by periods of drought.

Now, I would have to dig for the references on this, but I do believe I've seen a report recently that your body actually absorbs water more efficiently when it's cold than when it's hot. I can't remember the specifics of that report, so just take the general substance: you don't save your body a big effort or absorb more of the fluid by drinking warm/RT water. How much more efficiently, I don't know. Remember, room temp is going to be roughly 25 - 27C / 70 - 75F, and cold is going to be around, what? 4 - 12C / 35 - 45F? Doesn't matter too much; it's dropping into a 37C / 97F, i.e. much warmer system either way. It heats up fast.

 

[DandyDon]

:grad: Thanks fellow. Appreciate your help here. :grwow:

don

 

[Albion]

cliffdiver once bubbled...
Okay, uh, but not really. Your body doesn't really have any system with which it detects cold liquids directly and heats them up so you can absorb them. Your body doesn't spend any extra energy/calories heating up the liquids.

no it doesnt try to heat them up, but your body does expend energy in trying to keep itself warm. You are burning calories through heat loss to the surrounding water during the dive and by introducing cold liquids inside you it is making it work harder. I met someone who claimed to get very dry mouth whilst diving and she had a camelback type bladder stuffed down her wetsuit containing warm OJ, she had tried the cold stuff but said she was frozen by the end of the dive.

Surely most dehydration from diving is just that, without much loss in salts and so water would be best solution?

In my medical kit i carry a rehydration powder, but not sure what is in it. A few years ago i got a bad dose of food poisoning and my doctor recommended water with glucose powder mixed for rehydration, that seemed to work pretty good.

 

[cliffdiver]

Albion once bubbled...


no it doesnt try to heat them up, but your body does expend energy in trying to keep itself warm. You are burning calories through heat loss to the surrounding water during the dive and by introducing cold liquids inside you it is making it work harder. I met someone who claimed to get very dry mouth whilst diving and she had a camelback type bladder stuffed down her wetsuit containing warm OJ, she had tried the cold stuff but said she was frozen by the end of the dive.

Surely most dehydration from diving is just that, without much loss in salts and so water would be best solution?

Yeah, Albion, you're right. IMO, your body doesn't spend energy directly on heating up cold drink. A lot of your body's caloric expenditure on basal is just on homeostasis - you remember, all that temperature regulation, keeping you warmer than the surrounding air, etc. In water, of course, yeah, you will spend lots more energy keeping yourself warm. Of course, how much depends on exposure suit, Cozumel vs. Pacific Northwest, etc. And yes, sure, that's one reason why we need to get some more calories into us when we're diving. Your body can be engaged in "intense activity" even when it's not running or power hiking, i.e. struggling hard to get warm because you chose to dive in 70 degree water in a 3mm Anyway, even "relaxed" diving is more strenuous than it might seem.

Yeah, most dehydration from diving is going to be from water loss at a rate that is higher vs. salts than if you're also actively sweating. So, no, you're right, you won't need so much electrolyte replacement. But, you will need some, and you still rehydrate more effectively if your water's also got some salts in it, and/or, as your doc suggested, some glucose.

I'd bet you lots that your doc's rehydration solution contained both glucose and salts.

 

[Albion]

cliffdiver once bubbled...


Yeah, Albion, you're right. IMO, your body doesn't spend energy directly on heating up cold drink. A lot of your body's caloric expenditure on basal is just on homeostasis - you remember, all that temperature regulation, keeping you warmer than the surrounding air, etc. In water, of course, yeah, you will spend lots more energy keeping yourself warm. Of course, how much depends on exposure suit, Cozumel vs. Pacific Northwest, etc. And yes, sure, that's one reason why we need to get some more calories into us when we're diving. Your body can be engaged in "intense activity" even when it's not running or power hiking, i.e. struggling hard to get warm because you chose to dive in 70 degree water in a 3mm Anyway, even "relaxed" diving is more strenuous than it might seem.

Yeah, most dehydration from diving is going to be from water loss at a rate that is higher vs. salts than if you're also actively sweating. So, no, you're right, you won't need so much electrolyte replacement. But, you will need some, and you still rehydrate more effectively if your water's also got some salts in it, and/or, as your doc suggested, some glucose.

I'd bet you lots that your doc's rehydration solution contained both glucose and salts.

Sounds reasonable you got me on the technicalities. I read an article a while back about the top ten sports for burning calories.

At 1 Boxing, pretty logical a hard workout
At 2 Skiing, i belive this meant cross country, again makes sense
At 3 Scuba Diving!!!! Well even a tough dive is not that strenuous (well 9.5 times out of ten) so i put this fact down to heat loss!

Anyone care to comment!

 

[DORSETBOY]

Gatorade also works well as an excellent hangover cure. In Thailand we used to knock back about a litre of water with gatorade powder on the boat going out for the morning dive - Best way to deal with the post party hangover!

 

[cliffdiver]

Albion once bubbled...


At 1 Boxing, pretty logical a hard workout
At 2 Skiing, i belive this meant cross country, again makes sense
At 3 Scuba Diving!!!! Well even a tough dive is not that strenuous (well 9.5 times out of ten) so i put this fact down to heat loss!

Well, of course there is always a "it depends," and as much as anything this depends on how intensely you engage in a given activity. But if you look at "calories burned per unit body mass (kg) per unit time (usually: hour)" then there is no way that scuba diving is going to be up there in the company of such intense stuff as cross country skiing, running, good hard cycling (if not racing), boxing, rowing, etc.

I think it's up there, however. The calculation isn't that complex, and there are sites all over the Internet where you can plug in your weight, height and such and find out how many calories you'll burn/hour for a given exercise.

I recently plugged numbers into such a site and came out with this: I burn roughly 800-900 calories/hour running, and 450-500 calories/hour scuba diving.

 

[nwdiver2]

Drink water take salt tablets, drink more water. Keep hydrated, beer must be replaced with water as the beer goes through without hydrating.

 

[DandyDon]

nwdiver2 once bubbled...
Drink water take salt tablets, drink more water. Keep hydrated, beer must be replaced with water as the beer goes through without hydrating.

:beer:
I think beer will hydrate some - just not as much as water. Drink twice as much beer... :cluck:

don

 

[Albion]

dandydon once bubbled...

:beer:
I think beer will hydrate some - just not as much as water. Drink twice as much beer... :cluck:

don

And of course based on the survival of the herd theory it will make you smarter. By drinking beer you will kill off some brain cells which will be the weaker brain cells (of the herd), and thus make you smarter.

a win win situation folks