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Date: 24 Aug 2006 15:08:04
From: Bucky
Subject: experts: drink when thirsty
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Here's the latest mind-blowing advice from experts: drink when thirsty.
http://news.yahoo.com/s/nm/20060824/hl_nm/marathoners_hydration_dc
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Date: 24 Aug 2006 17:51:43
From:
Subject: Re: experts: drink when thirsty
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runsrealfast wrote:
> Man thats great news, wow now when i'm thirsty I can have a
> drink.<---being sarcastic,
> John
_
Thousands of runners are told to systematically hydrate as a matter of
procedure periodically even though they don't sense thirst. We're
told by the time we sense thirst, it's too late. The article is
debunking this lore. This lore is prevelant, people assume it's a
universal truth, hell right in this thread this Kaz person is repeating
this lore. This is entrenched lore in running circles....and the
article debunks it....this is hardly "no brainer content" worthy of
mocking, etc.
I can race a Spring or Fall Half Marathon here in the North East and
feel no desire to hydrate. If I do, it might be to wash down some Gel,
that's it. I've also had Spring & Fall Half Marathons wherein I did
follow the "lore" and hydrated every 3 - 4 miles...and yup, felt
slighly bogged down in the those final miles.
I don't hydrate w/I train on my 9 mile runs even in the Summer. The
article is basically saying the lore "ain't quite on spot / right and
ymmv".
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Date: 25 Aug 2006 16:09:12
From: Dan Stumpus
Subject: Re: experts: drink when thirsty
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Lance, Lance, Lance...
Here's some info gleaned from this site, although you can find confirmation
all over the physiology literature. My comments are in parentheses.
http://www.ultracycling.com/nutrition/electrolytes.html
Weight Loss Consequences
0 to 2 % beginning thirst, performance loss at 1.8%
2 to 3 % thirst, 7% performance loss
3 to 6 % cramps, strong thirst, 20% performance loss
> 6 % severe cramps, heat exhaustion, coma, death
(Confirmation of my constant harping to maintain hydration to prevent
cramps)
.....
Normal sweat rates can range from 0.75 to 2 Liters/hour, depending on
conditions such as temperature, humidity, pace, clothing, and the degree of
heat acclimation the rider has. A rate of one Liter/hour is not uncommon for
an acclimated cyclist. At that rate, typical electrolyte loss rates by sweat
are 1,300 mg/hr for sodium, and 230 mg/hr for potassium.
(Note that is about 1/2 - 1 teaspoon of salt, in layman's terms, or 1-2
Succeed caps)
Early in the event, sweat rates and sodium loss rates are high. Urination
amounts may be high too. As sodium levels fall, the body increases the level
of the hormone aldosterone that influences kidney function to slow sodium
loss. As exercise continues and sodium is lost, blood pressure may fall. The
body produces the hormone vasopressin to help maintain blood pressure. If
exercise continues, with more water and electrolyte losses, performance
begins to suffer and athletes slow down. Since sodium is important for the
absorption of food and water from the digestive tract, what the cyclist eats
and drinks is not absorbed. Nausea results. Even the sight of food may make
one want to retch. This is your body's way of telling you "Don't bother
because I can't process it even if you force yourself to eat." If you drink,
the water won't be absorbed well and will slosh around in the stomach. What
is absorbed cannot be retained and will soon be urinated out.
(The body needs to pump sodium into the stomach to make the water salty
before it can be absorbed. If you're low on salt, it would be dangerous to
dilute your sodium concentration further, hence the queasiness)
As the level of sodium in the blood decreases, the ratio of sodium to water
decreases to dangerous levels. As a defense mechanism, water will be moved
from the blood into the spaces around body cells. That is why hands and feet
can swell after many hours of competing.
(I have noticed that you get mental status changes at this point -- that
glassy stare and "whatever" attitude, and an unwillingness to say more than
a word or two)
Loss of water from the blood stream is equivalent to further dehydration,
causing additional loss of performance. Such conditions lead to a DNF or
misery all the way to the finish line.
.....
So Lance, go ahead and run your races finishing 3-4% lighter at the end.
It's done all the time. But it will slow you down...
-- Dan
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Date: 25 Aug 2006 17:19:55
From: Donovan Rebbechi
Subject: Re: experts: drink when thirsty
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On 2006-08-25, Dan Stumpus <dstumpus_NOSP@mindspring.com > wrote:
> 3 to 6 % cramps, strong thirst, 20% performance loss
> > 6 % severe cramps, heat exhaustion, coma, death
"The Nevada Desert Study revealed the following (Noakes 1993):
...
There were no immediate health risks associated with the levels of
dehydration (7%-10%) that were present at the termination of the
exercise"
Noakes, Lore of Running
Most people will be pretty damn thirsty long before they reach 7%.
Cheers,
--
Donovan Rebbechi
http://pegasus.rutgers.edu/~elflord/
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Date: 25 Aug 2006 17:14:34
From: Donovan Rebbechi
Subject: Re: experts: drink when thirsty
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On 2006-08-25, Dan Stumpus <dstumpus_NOSP@mindspring.com > wrote:
> Lance, Lance, Lance...
>
> Here's some info gleaned from this site, although you can find confirmation
> all over the physiology literature. My comments are in parentheses.
>
> http://www.ultracycling.com/nutrition/electrolytes.html
>
> Weight Loss Consequences
> 0 to 2 % beginning thirst, performance loss at 1.8%
> 2 to 3 % thirst, 7% performance loss
> 3 to 6 % cramps, strong thirst, 20% performance loss
Poppycock. What is this based on ?
I usually feel pretty good within 5lb of starting weight (3%). I'm OK if I
finish within about 5%. I've *never* had cramps on a run or during a race.
I certainly don't get 20% performance loss (or any observable performance loss
for that matter) at 3-6%. If that were true, I'd be in the low 7s for the last
mile at the half marathon.
Noakes has a lengthy discussion on this which is more or less consistent with my
experience.
Cheers,
--
Donovan Rebbechi
http://pegasus.rutgers.edu/~elflord/
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Date: 26 Aug 2006 04:30:12
From: Dan Stumpus
Subject: Re: experts: drink when thirsty
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"Donovan Rebbechi" <abuse@aol.com > wrote
>> Weight Loss Consequences
>> 0 to 2 % beginning thirst, performance loss at 1.8%
>> 2 to 3 % thirst, 7% performance loss
>> 3 to 6 % cramps, strong thirst, 20% performance loss
>
>
> Poppycock. What is this based on ?
Actually, I should have excised that. (I was "working" when I composed that
in the midst of umpteen interruptions) I've seen numbers all over the place,
and the 7% number *is* way off my experience. Apologies.
My personal experience suggests a 2% (maybe 10 secs/mile) for 3-4% weight
loss, if it isn't hot. If hot, it's hard to unconfound the heat and
dehydration parameters.
You also get a boost from being losing that weight. This effect is greater
than it is for cycling, since we runners are constantly accelerating our
body weight as we leap and land, and the cyclist is pushing against friction
(mostly wind).
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Date: 25 Aug 2006 15:31:17
From: Donovan Rebbechi
Subject: Re: experts: drink when thirsty
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On 2006-08-25, lanceandrew@aol.com <lanceandrew@aol.com > wrote:
> I don't hydrate w/I train on my 9 mile runs even in the Summer. The
The tricky thing with hydration is that it's very non-linear. On a 9 mile run,
you still water at a fairly rapid rate, but as long as it's less than 5lb, you
can probably get through the run and just drink at the end. The key point is
that you can make it from start to finish on a single full tank of gas. You don't
really get any adverse effects until you're close to empty. Like you, I'd never
take water on a training run less than 12 miles long.
But with a longer run, like 18 miles, you'd not only need to top up, you
probably want to take your first drink before the 9 mile mark. So on an 18 mile
run, I'd ideally drink at 3,9 and 15 miles (in central park, I'll stop at a
fountain on the opposite side from where I start).
Cheers,
--
Donovan Rebbechi
http://pegasus.rutgers.edu/~elflord/
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Date: 24 Aug 2006 17:37:37
From:
Subject: Re: experts: drink when thirsty
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Kaz Kylheku wrote:
> ... it's bullshit advice. By the time you are thirsty, it may be too
> late to start rehydrating, particularly in hot weather.
_
the article directly addressed and debunked the lore you are now
repeating. yet and still you call it bullshit advice? might you have
the slightlest bit of foundation for your characterization?....perhaps
credentials and research trumps that found in the article?
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Date: 25 Aug 2006 01:52:44
From: Doug Freese
Subject: Re: experts: drink when thirsty
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<lanceandrew@aol.com > wrote in message
news:1156466257.387404.240300@75g2000cwc.googlegroups.com...
>
> Kaz Kylheku wrote:
>> ... it's bullshit advice. By the time you are thirsty, it may be too
>> late to start rehydrating, particularly in hot weather.
> _
>
> the article directly addressed and debunked the lore you are now
> repeating. yet and still you call it bullshit advice? might you
> have
> the slightlest bit of foundation for your characterization?....perhaps
> credentials and research trumps that found in the article?
I can only speak for me and I'm very familiar with the science and how
it has changed, yet it hasn't. The recent drama with people getting
severely sick or croaking from hyponatremia has science people scurrying
around trying to make global statements to prevent these situations from
repeating. Admirable thought but poppycock.
In all my races for 20+ years I have never waited until I felt thirsty
to drink nor wait until I get cramps to take some salt. I still think
that weighing yourself before and after a run, trying to keep and eye on
temp and humidity, will tell each person how much fluid they need. The
only trouble with Global statements is they don't apply to everyone.
Know thyself and don't trust the "globalists!!!!! "
-Doug
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Date: 25 Aug 2006 15:35:05
From: Donovan Rebbechi
Subject: Re: experts: drink when thirsty
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On 2006-08-25, Doug Freese <dfreese@hvc.rr.com > wrote:
>
> to drink nor wait until I get cramps to take some salt. I still think
> that weighing yourself before and after a run, trying to keep and eye on
> temp and humidity, will tell each person how much fluid they need. The
This worked like charm for me. It also taught me that it's pretty hard to drink
too much water on a hot day (and also that heat makes a huge difference). In
hot weather, I drink as much as I can get down comfortably. Curiously enough,
I can get through winter runs just fine without taking water at all.
Cheers,
--
Donovan Rebbechi
http://pegasus.rutgers.edu/~elflord/
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Date: 25 Aug 2006 07:18:23
From: Dominic Shields
Subject: Re: experts: drink when thirsty
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On Fri, 25 Aug 2006 01:52:44 GMT, "Doug Freese" <dfreese@hvc.rr.com >
wrote:
>I can only speak for me and I'm very familiar with the science and how
>it has changed, yet it hasn't. The recent drama with people getting
>severely sick or croaking from hyponatremia has science people scurrying
>around trying to make global statements to prevent these situations from
>repeating. Admirable thought but poppycock.
>
>In all my races for 20+ years I have never waited until I felt thirsty
>to drink nor wait until I get cramps to take some salt. I still think
>that weighing yourself before and after a run, trying to keep and eye on
>temp and humidity, will tell each person how much fluid they need. The
>only trouble with Global statements is they don't apply to everyone.
>Know thyself and don't trust the "globalists!!!!! "
Interesting how we all read things differently, I got a distinct "Hey
- do your own thing man" . . . . *inhales deeply* vibe.
<quote >
In their latest position statement on the topic, they assert that
there is no "blanket advice" to give to people about how much fluids
are needed while exercising. Instead, they write, athletes should be
encouraged "to explore, understand and be flexible toward their own
needs."
"Athletes should learn to trust the sensation of thirst, rather than
adhere to rigid guidelines that do not allow for the flexibility that
is needed in a dynamic race situation," co-author Dr. Tamara
Hew-Butler, of the University of Cape Town in South Africa, told
Reuters Health.
<end quote >
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Date: 24 Aug 2006 15:47:48
From: Kaz Kylheku
Subject: Re: experts: drink when thirsty
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Bucky wrote:
> Here's the latest mind-blowing advice from experts: drink when thirsty.
>
> http://news.yahoo.com/s/nm/20060824/hl_nm/marathoners_hydration_dc
... it's bullshit advice. By the time you are thirsty, it may be too
late to start rehydrating, particularly in hot weather.
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Date: 24 Aug 2006 15:12:34
From: runsrealfast
Subject: Re: experts: drink when thirsty
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Bucky wrote:
> Here's the latest mind-blowing advice from experts: drink when thirsty.
>
> http://news.yahoo.com/s/nm/20060824/hl_nm/marathoners_hydration_dc
Man thats great news, wow now when i'm thirsty I can have a
drink.<---being sarcastic, now being serious-- > I hope this wasn't paid
for by federal funds.
John
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Date: 25 Aug 2006 15:24:05
From: Donovan Rebbechi
Subject: Re: experts: drink when thirsty
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On 2006-08-24, Bucky <uw_badgers@email.com > wrote:
> Here's the latest mind-blowing advice from experts: drink when thirsty.
>
> http://news.yahoo.com/s/nm/20060824/hl_nm/marathoners_hydration_dc
It might sound obvious, but it's actually controversial and IMO probably wrong.
The reason they are arguing this is because they are concerned about hypotraemia
related deaths.
I agree with the people who say that you shouldn't wait until you actually feel
thirsty, but the article makes some good commonsense points about maybe holding
off a little bit if you feel water sloshing around in your stomach.
I experimented with weigh-ins during summer runs at one stage, and it really is
quite difficult to drink too much water in hot weather. Unless you're force-feeding
yourself, you're probably not drinking too much.
Cheers,
--
Donovan Rebbechi
http://pegasus.rutgers.edu/~elflord/
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Date: 25 Aug 2006 16:12:42
From: Dan Stumpus
Subject: Re: experts: drink when thirsty
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"Donovan Rebbechi" <abuse@aol.com > wrote
> I agree with the people who say that you shouldn't wait until you actually
> feel
> thirsty, but the article makes some good commonsense points about maybe
> holding
> off a little bit if you feel water sloshing around in your stomach.
If you're dehydrated, this means take more salt.
If you've over hydrated, this means take more salt (to prevent
hyponatremia).
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Date: 25 Aug 2006 16:59:26
From: Donovan Rebbechi
Subject: Re: experts: drink when thirsty
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On 2006-08-25, Dan Stumpus <dstumpus_NOSP@mindspring.com > wrote:
>
> "Donovan Rebbechi" <abuse@aol.com> wrote
>
>> I agree with the people who say that you shouldn't wait until you actually
>> feel thirsty, but the article makes some good commonsense points about maybe
>> holding off a little bit if you feel water sloshing around in your stomach.
>
> If you're dehydrated, this means take more salt.
>
> If you've over hydrated, this means take more salt (to prevent
> hyponatremia).
If you're fit, and it's a <3hr run, you're probably neither of the above, which
means "salt is over-rated".
Hyponatremia is also over rated. It only became an issue when the ranks of
marathons were stacked with 5hr+ plodders. IMO these people shouldn't be running
marathons in warm weather.
Cheers,
--
Donovan Rebbechi
http://pegasus.rutgers.edu/~elflord/
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Date: 26 Aug 2006 13:03:56
From: Doug Freese
Subject: Re: experts: drink when thirsty
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"Donovan Rebbechi" <abuse@aol.com > wrote in message
news:slrneeub3f.m3r.abuse@panix2.panix.com...
> On 2006-08-25, Dan Stumpus <dstumpus_NOSP@mindspring.com> wrote:
>>
>> "Donovan Rebbechi" <abuse@aol.com> wrote
>>
>>> I agree with the people who say that you shouldn't wait until you
>>> actually
>>> feel thirsty, but the article makes some good commonsense points
>>> about maybe
>>> holding off a little bit if you feel water sloshing around in your
>>> stomach.
>>
>> If you're dehydrated, this means take more salt.
Maybe. One could simply be under watered. I could have just muched in
entire bag of chips and tossed down a few Succeed caps. This may drive
one's system to crave fluids but is not a solution to lack of soultion.
While hypernatremia is less common it still happens.
Fact! Too much or too little salt causes the stomach to stop absorbing.
>> If you've over hydrated, this means take more salt (to prevent
>> hyponatremia).
But if one experiencing some degree of hypernatremia more salt will get
you a body bag. For you this works because you tend to under salt and
wait to feel cramps. For someone else with different input this can be
completely wrong if not dangerous advice.
My main point about this whole topic- global statements such as "only
drink when you thirsty" or either of your two above always need to be
qualified and why I say know thyself. There are to many variables to
conclude a simple answer.
> If you're fit, and it's a <3hr run, you're probably neither of the
> above, which
> means "salt is over-rated".
>
> Hyponatremia is also over rated. It only became an issue when the
> ranks of
> marathons were stacked with 5hr+ plodders.
The longer the time the more we beg hyponatremia. Since you are
quicker and stay with marathons and less, hyponatremia is less of an
issue. For us in the ultra world hyponatremia is as common as pregnancy
in a maternity ward. If we don't keep ourselves balanced from the start
be it long run or long race you at least DNF if not worse.
> IMO these people shouldn't be running marathons in warm weather.
That's not a fair statement but you did preface it with "opinion." They
just need to get smarter about their fluid/salt/etc needs not draw some
elitist line at time. I have a lot of friends that run 5 hours marathons
in all heat conditions just fine. They are just slow in pace abilities.
-Doug
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Date: 25 Aug 2006 08:04:22
From: runsrealfast
Subject: Re: experts: drink when thirsty
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lanceandrew@aol.com wrote:
> I can race a Spring or Fall Half Marathon here in the North East and
> feel no desire to hydrate. If I do, it might be to wash down some Gel,
> that's it. I've also had Spring & Fall Half Marathons wherein I did
> follow the "lore" and hydrated every 3 - 4 miles...and yup, felt
> slighly bogged down in the those final miles.
I hear what you are saying lance. I have done runs where I feel like my
stomace is full of water and I can hear the sloshing.
John
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Date: 25 Aug 2006 13:53:08
From: Bucky
Subject: Re: experts: drink when thirsty
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Dan Stumpus wrote:
> If you're dehydrated, this means take more salt.
> If you've over hydrated, this means take more salt (to prevent
> hyponatremia).
Do you happen to have high blood pressure? That's a lot of salt! =)
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Date: 26 Aug 2006 04:44:47
From: Dan Stumpus
Subject: Re: experts: drink when thirsty
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"Bucky" <uw_badgers@email.com > wrote
> Do you happen to have high blood pressure? That's a lot of salt! =)
90/55 last time my dor checked it. He said "Don't let it get any
lower!".
I eat tons of salty food (love mexican, chinese, etc). I think only a
minority of people are blood-pressure sensitive to salt.
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Date: 26 Aug 2006 08:25:20
From: Kaz Kylheku
Subject: Re: experts: drink when thirsty
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lanceandrew@aol.com wrote:
> runsrealfast wrote:
> > Man thats great news, wow now when i'm thirsty I can have a
> > drink.<---being sarcastic,
> > John
> _
>
> Thousands of runners are told to systematically hydrate as a matter of
> procedure periodically even though they don't sense thirst. We're
> told by the time we sense thirst, it's too late. The article is
> debunking this lore. This lore is prevelant, people assume it's a
> universal truth, hell right in this thread this Kaz person is repeating
> this lore.
Say, Lance person, don't you have some fast little transvestites to
chase down?
What you are calling lore is attributed to the American College of
Sports Medicine by that very article itself.
I take that institute to be more credible than some worldwide gang of
marathon medical directors, who even happen to have a conflict of
interest in this subject matter.
>This is entrenched lore in running circles....and the
Entrenched for good reason, I might add.
> article debunks it....this is hardly "no brainer content" worthy of
> mocking, etc.
The article does no such thing. It actually reiterates some of the
facts which support the theory the idea that thirst may an unacceptably
late indicator. For instance, the fact that more water is lost through
sweating than is regained by voluntary hydration. This means that the
longer you delay hydration, the farther you fall behind and the less
water you will have left in you at the finish.
I had a good laugh at the article's lame attempt to discredit the
existing theory by describing it as historic: that the ACSM has
"historically" claimed so. The subtle implication is that something
historic is outdated and wrong.
That's about the extent of the debunking.
> I can race a Spring or Fall Half Marathon here in the North East and
> feel no desire to hydrate.
What are the temperatures like? How about full marathons?
> If I do, it might be to wash down some Gel,
> that's it. I've also had Spring & Fall Half Marathons wherein I did
> follow the "lore" and hydrated every 3 - 4 miles...and yup, felt
> slighly bogged down in the those final miles.
>
> I don't hydrate w/I train on my 9 mile runs even in the Summer.
Are you citing these experiences as evidence against the accepted
theory, or in support of it?
It appears that in the situations you described, you did not follow the
protocol of waiting for thirst as a signal to rehydrate. Either you
finished the run before that occured, or you drank before getting
thirsty.
My experiences are similar. In mild weather, I don't bother rehydrating
on 8 to 13 mile runs at all. I've gone as far as 18 miles without
rehydrating, in cool weather. So what? I'm counting on finishing before
losing too much water. Does that mean I could avoid rehydrating for
the first 13 miles of a marathon? Hardly.
> The article is basically saying the lore "ain't quite on spot / right and
> ymmv".
The only sense in which the accepted theory is not quite on the spot is
that it sometimes leads to poor interpretations and corresponding
actions. It's not correct to follow some absolute drinking rates, like
1600 cc/h for everyone. Nor is it correct to try to replace all fluids
lost, without the inclusion of electrolytes.
The basic theory is right---or, at least, the article does not show
otherwise. Moreover, it completely screws up with that whole
recommendation about thirst. That is just another "one size fits all"
recommendation that does not work for everyone in all situations.
What's going on is clearly that these medical directors are under
pressure to revise their recommendations, in the light of the recent
sensational hoopla surrounding hyponatremia. With this lame answer,
they are cleverly washing their hands of responsibility.
The next time someone dies of hyponatremia in the middle of a marathon,
the medical director can say that his official recommendation was not
followed: the individual drank in spite of not being thirsty. Who can
prove otherwise? A dead jogger can't say whether or not he or she was
thirsty.
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