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-   -   Exercise Associated Hyponatremic Encephalopathy, Gatorade and the ACSM (https://board.crossfit.com/showthread.php?t=86218)

Brian Chontosh 03-06-2014 08:20 PM

Re: Exercise Associated Hyponatremic Encephalopathy, Gatorade and the ACSM
 
"A key to athletic success is [I]avoidance[/I] of a state of [I]underhydration[/I]. …people rely on 'thirst' as an alarm bell for when to drink. Thirst, however, is a delayed sensation that does not occur until the person has already lost 1 to 2L of fluid. … Because of this, athletes should learn to consume fluids on a fixed time interval rather than relying on thirst for when to drink."

"Staying optimally hydrated… has multiple benefits, including:… a less pronounced body core temperature, improvement in skin blood flow (enabling better sweat rates and improved cooling)"

"Fluid intake recommendations are to… drink as much as needed to match sweat loses… not rely on thirst as a stimulus to drink (the thirst sensation will only occur after 1 to 2L (1 to 2% of body weight) has already been lost)."

"Sweat rates are often 1 to 2L per hour, and it is difficult to consume and absorb enough fluid to match these loses."

"Ingesting large volumes of dilute, low- (or no-) sodium fluid may increase the risk of hyponatremia."

"…athletes will often develop dehydration when there are sufficient fluids nearby for them to consume"

[SIZE="1"][B]Bushman, Battista,... American College of Sports Medicine (2014). ACSM'S RESOURCES FOR THE PERSONAL TRAINER, 4th Ed. Lippincott Williams and Wilkings. Chapter 6; pp177-191.[/B][/SIZE]

Any one of these statements taken singularly might sound fairly reasonable (despite this message board thread's continued references that suggest they are inaccurate/unfounded). But, allow me to link the chain for what we are given...

The key is to drink. I am not thirsty now but I should start soonest because thirst isn't on time. This drinking will keep my body cooler and increase the ability to sweat so I can cool, my already cooler, body better. Then, drinking more helps me sweat more so that I will need to replace more water losses and do so faster, else I become [I]underhydrated[/I] again. Unfortunately, my body already can not keep up with sweat losses because I can not consume and absorb well enough anyways. And even though there are already ample fluids around for me to drink, I will fail to consume them.

If I were to quote concepts around respiratory loses (which I've briefly researched and find to be pretty much irrelevant compared to urinary and sweat loses) and the strategy/methodology with considering this, it compounds the issue a third way into contradiction to drink more because of the effects despite the causes and requirements are opposite to the said situation of the effects that are needed. Uhm... right effects but for the wrong situation. Nevermind.

"To ensure better athlete compliance, fluids should be cool and taste good…" [same source]

The answer? Let them drink Sports Drinks. Cool and really tasty Sports Drinks. Show pictures of athletes using Gatorade drinks (fig 6.10, 6.11, 6.12) and listing Gatorade products by name in tables (6.15).

I refuse to consider what the 'pre-sportdrink man' ever did to survive in the efforts against nature when he only had water.

What is of more interest is the publish date; 2014. This is the latest and greatest information that the ACSM is propagating. A text that is updated every 4 years (2001, 2006, 2010). This is the primary source used to study, test and receive their CPT certification. Hyponatremia is mentioned one time (EAH zero times) in 14 pages of fluid and hydration guideline text, yet it may affect over 13% of endurance athletes. Chapter 6 references do not include any of the more recent scientific publications regarding fluid and hydration post 2000 other than their own publications or those from the GSSI. Every scientific reference provided by Russell Greene calls into question, at worst, or flat out contradicts, at best, the arguments that tie these fluid statements of requirement/interest together.

((Sidenote: HomeOwner's Associations got greater word count hits in their marketing and sales sections of Business Basics and Planning; even received an Index entry.))

It is really almost as if a collection of 'research' was gathered, some interesting points are pulled from each of them fairly independently, and presented as a collage of factoids. In the end, the final position really is 'every athlete is different and you will need to take caution to stay hydrated at all times, when in doubt, drink a sports drink'. I can not accept this as science - especially after reading [U]Waterlogged[/U] and 100's of pages of separate and supporting scientific research.

If these things are so obvious (and I understand that they appear so because we are diligently investigating) what else in the entire curriculum is suspect? What is the supervising body that truly reviews this material for accuracy? Better asked maybe is who do they work for - public health and safety or $$$? At least in the Fluids and Hydration section, everything appears to be self-referential, without any real scientific strength, and built like an elementary textbook. How do they have the credibility that they claim?

In my personal domain of interest, my concern is that there is a significant reluctance to decouple the relationship of Dehydration from Heat Injury. At least a reconciliation of the appropriate nature of the relationship is begged between the two. My hope is that as we kick the door open further, events like cramping, rhabdomyolysis, hypothermia, and others will take different shapes. My fear is that if we don't decouple the GSSI from the ACSM (and the other many private interest funded relationships in our health and fitness community) we will never be able to make the necessary progress.

I am hesitant to dig into the "High Carb, Low Fat diet for performance" that precedes this subchapter.

Brian Chontosh 03-06-2014 08:39 PM

Re: Exercise Associated Hyponatremic Encephalopathy, Gatorade and the ACSM
 
In all fairness and credit, in the ACSM's Guidelines for Exercise Testing and Prescription, 9th ED (2014) pp218, hyponatremia receives two word hits.

They define EAH as a state of lower than normal blood sodium (typically <135) and then:

"Hyponatremia tends to be more common in long duration physical activities and is precipitated by consumption of hypotonic fluid (water) alone in excess of sweat losses (typified by body weight gains). The syndrome can be prevented by not drinking in excess of sweat rate and by consuming salt-containing fluids and foods…"

They then politely ask you to refer to the ACSM 2007 Position Stand on fluid replacement for further information.

What isn't being said is more damaging than the suspect items that are and how they are being said.

Ask them how we determine sweat rates so we can match and not exceed them. Certainly we do not want to fall short of them else the dangerous [I]underhydration[/I].

They answer "it is very complex". I rebut: thirst is pretty simple, water is pretty economical."

Graham Leck 03-07-2014 12:55 AM

Re: Exercise Associated Hyponatremic Encephalopathy, Gatorade and the ACSM
 
I would be interested in a book if any left.
Graham.

[COLOR="Blue"][I]on the list! ~Lynne[/I][/COLOR]

Preston Sprimont 03-07-2014 11:55 AM

Re: Exercise Associated Hyponatremic Encephalopathy, Gatorade and the ACSM
 
[QUOTE=Coach;1222579]

To date nothing adverse has been demonstrated in under drinking during athletic competitions yet at least a dozen deaths and thousands of injuries have resulted from over drinking. [/QUOTE]

"Under drinking" seems kind of vague, so I guess it depends on how that's defined... but as far as I know, dehydration (do we have a working definition for dehydration for this discussion yet?) can still pose health risks; and, to my knowledge, there is record of injury and death occurring from dehydration. Again, "under drinking" is not defined here; if defined as less hydration than optimal, sure, there's a good chance there's no evidence of injury and death; if defined as less than necessary, however, I imagine we are entering the realm of health-risk-posing dehydration. But I'm not interested in arguing semantics ad nauseum...
My point is this: let's not demonized hydration. Yes, the GSSI and ACSM have skewed, distorted, and butchered the science, seemingly to their benefit, and have disseminated and advertized and pushed this "information" at the expense of the public's knowledge and of some individuals' health. They are in the wrong here. That has been thoroughly demonstrated. However, hydration is not the enemy. Hydration does not threaten the public health or the health of athletes. Super-hydration to the point of hyponatria is the problem. Yes, we all know hydration is important, and maybe that's why it hasn't received much mention here, but I'd hate to see the responses (which are intended to educate and expose) to the GSSI's and ACSM's erroneous claims and falsified science be tainted by error on the opposite end of the spectrum.
If I am in error in claiming that dehydration poses a health risk, and if hydration is in fact an issue, I'm all ears.

Cliff notes: hydrate, but not too much.

Edit/note: I quoted Coach Glassman here because his succinct statement about over- and under-drinking directly addresses what I wanted to comment on, but my comment is a "reply" to many of the quotes in this thread from a number of users that expressed such a sentiment.

Jeff Glassman 03-07-2014 11:57 AM

Re: Exercise Associated Hyponatremic Encephalopathy, Gatorade and the ACSM
 
[QUOTE=Dakota Base;1220500]
While deaths from faulty data are tragic, I don't think the format in which you're fighting this "war" is productive, or ethical. Coach's arguement here is passing off that the ACSM/Gatorade are STILL promoting hyperhydration, which just isn't true.[/QUOTE]

Part I of II:

ACSM promoted incompetent, if not unconscionable, over-drinking in its 1996 [i]Position Stand: Exercise and Fluid Replacement[/i], written by Victor A. Convertino, (Chair), Lawrence E. Armstrong, Edward F. Coyle, Gary W. Mack, Michael N. Sawka, Leo C. Senay, Jr., and W. Michael Sherman. The names will prove important.

All hold PhDs, and all are Fellows of the ACSM. Convertino and Sawka, who may have retired, at one time were Research Physiologists with the US Army, Convertino at the Institute of Surgical Research (USAISR), and Sawka at the Research Institute of Environmental Medicine (USARIEM). Sawka was on the [i]Panel on Dietary Reference Intakes for Electrolytes and Water[/i], L.J. Appel (Chair), 2005 (Appel (2005)). Sawka chaired the ACSM revision of its [i]1996 Position Stand[/i] in 2007, with five co authors, including Scott J. Montain. Here is a capsule summary of ACSM’s Positions:
[indent]>>During exercise, athletes should start drinking early and at regular intervals in an attempt to consume fluids at a rate sufficient to replace all the water lost through sweating (i.e., body weight loss), or consume the maximal amount that can be tolerated. Convertino, V.A., et al., (1996) [i]ACSM Position Stand, Exercise and Fluid Replaceme[/i]nt, p. 517.[/indent]
Updated to read:
[indent] >>The goal of drinking during exercise is to prevent excessive (>2% body weight loss from water deficit) dehydration and excessive changes in electrolyte balance to avert compromised performance. Sawka, M.N., et al., (2007) [i]ACSM Position Stand, Exercise and Fluid Replacement[/i], p. 377.[/indent]
The latter introduces overdrinking, even considering possible health advantages, but allowing that it can be a threat to life. [i]Id.[/i], p. 381. However, it does not use the phrases [i]water intoxication[/i] or [i]water poisoning,[/i] a phenomenon known for almost a century. Rowntree, L.G., [i]Water Intoxication[/i], ArchIntMed, v32, n2, August 1923. ACSM now recognizes that overdrinking can cause hyponatremia, but not that the body normally reduces water volume during intense or prolonged work, just as it increases pulse rate.

[b]Definitional problems[/b]

Exercise physiologists almost exclusively refer to a reduction in body water as dehydration, measuring it as the ratio (percent) of body weight loss, impliedly referenced to some set point corresponding to steady state resting. Other physiologists use dehydration to mean a disease with symptoms similar to hyponatremia. Appel (2005), p. 163. Dehydration symptoms begin with thirst, then progress to include dry mouth, oliguria (low urine volume), dark urine, dry or inelastic skin, orthostatic hypotension (light-headedness upon standing) to syncope (fainting), and to confusion, organ damage, coma, and death. See [i]ICD10, E86.0, Dehydration[/i]; [i]Merck Manual [/i]online.

The two definitions, dehydration-as-weight-loss and dehydration-as-disease, are incompatible. ACSM’s [i]Position Stands[/i] try to medicate dehydration-as-disease by combatting dehydration-as-weight-loss with a glut of its favored sponsor’s product. The effect bristles with scientific arrogance as well as unethical conduct. This ACSM recommendation works against nature, trying to force the athlete into a presumed rest state while his body is trying to adjust its regulation for intense exercise.

[b]Homeostasis vs. Heterostasis[/b]

Perhaps ACSM’s recipe was attractive to physiologists who misunderstand homeostasis, the fundamental principle of their field that the body adjusts its parameters to maintain a well-state. The confusion lies in applying homeostasis to mean that the body has a unique well-state under all conditions.

That the human body does not have a unique set point is supported by the evidence from athletes under stress, as, for example, when pulse rate increases and heart stroke volume decreases. That the rest state is neither a unique set point nor the optimum under stress is recognized in modern physiology by the terms [i]heterostasis[/i] (multiple, discrete set points, attributed to Selye (1973)) and [i]allostasis[/i] (dynamic, adaptive set points, named by Sterling and Eyer (1988)). See Berntson, G.G. & J.T. Cacioppo, [i]Integrative Physiology: Homeostasis, Allostasis, and the Orchestration of Systemic Physiology[/i], Ch. 19 in J.T. Cacioppo, L.G. Tassinary, & G.G. Berntson (Eds), [i]Handbook of Psychophysiology[/i], 2007, 3ed Ed, NY: Cambridge University Press, p. 436.

[b]ACSM Prescribes MINIMUMs, never MAXIMUMs[/b]

Both the Convertino (ACSM PS 1996) and the Sawka (ACSM PS 2007) versions of Gatoraded physiology conclude with a prescription for the MINIMUM amounts to drink, without regard to any MAXIMUMs. For Convertino, the athlete was to lose no body weight by drinking as much as could be tolerated. Sawka removed the reference to “drinking the amount that can be tolerated”, but only lowered the maximum body weight loss from zero to 2%, still achieved by drinking beyond the body’s thirst signal. Neither [i]Position Stand[/i] recognized the danger of water intoxication.

To the contrary, several studies over the years investigated whether hyperhydration could be beneficial. Sawka, writing with Latzka in 1998, concluded that the only possible benefit of hyperhydration is that it delayed hypohydration during exercise. In 2001, Sawka went further, indicating that his 1998 study found not just no benefit, but in fact no effect at all from hyperhydration. Sawka, M.N. & K.B. Randolf, [i]Physical Exercise in Hot Climates: Physiology, Performance, and Biomedical Issues[/i], Ch. 3 in [i]Medical Aspects of Harsh Environments[/i], Vol. 1, Textbooks of Military Medicine, 2001, Table 3-3, p. 107.

[b]Sawka Leads the Army To Abandon MINIMUMs for MAXIMUMs[/b]

In fact for a decade, the U.S. Army conducted an experiment with hyperhydration, with disastrous results. Since 1988, the U.S. Army regulations set minimums for water intake. They were “At least ½” quarts/hour in the most benign environment, increasing to “At least 1” quarts/hour, then to “At least 1½” quarts/hour, and finally to “More than 2” quarts/hour. So drinking more than 2 quarts/hour would satisfy all conditions.

Sawka, writing behind Montain and Latzka, observed:
[indent]>>The U.S. Army's fluid replacement guidelines emphasize fluid replacement during hot weather training to prevent degradation of performance and minimize the risk of heat injury. Little consideration has been given, however, to possible overhydration and development of water intoxication. Sufficient epidemiological evidence is available to demonstrate an increasing incidence of water intoxication during military training. … revised guidelines will sustain hydration and minimize the number of heat injuries during military training while protecting the soldier from becoming sick from overdrinking. Montain, S.J., Latzka, W.A., & M.N. Sawka, [i]Fluid Replacement Recommendations for Training in Hot Weather[/i], July 1999, abstract.[/indent]
“Little consideration has been given” by whom?

From 1988 to 2000, the US Army prescribed MINIMUMs for water intake, which were at least 2 quarts per hour at a Wet Bulb Global Temperature of 90ºF or higher. This resulted in 190 hospitalizations between 1989 and 1999 for hyponatremia attributed to over-drinking. Kolka, M.A., W.A. Latzka, S.J. Montain, & M.N. Sawka, [i]Current U.S. Military Fluid Replacement Guidelines[/i], USARIEM, December, 2013, p. 6-1. In 2000, the Army, joined now by the US Marine Corps, revised the Army regulations following trials, replacing MINIMUMs entirely with MAXIMUMs for the first time, and emphasizing that the fluid of choice was water. The overarching regulation includes that hourly water intake should not exceed 1 1/4 quarts under any conditions, i.e., the intakes are MAXIMUMs.

[b]ACSM Continues To Defend Its Position Stand on Drinking MINIMUMs[/b]

ACSM has yet to follow suit, to set maximum fluid intake to prevent hyponatremia and water intoxication. Its [i]2007 Position Stand[/i], above, prepared by Sawka, still recommends a MINIMUM intake of fluid, preferably fortified water (aka Gatorade).

Continued

Jeff Glassman 03-07-2014 01:16 PM

Re: Exercise Associated Hyponatremic Encephalopathy, Gatorade and the ACSM
 
[QUOTE=Dakota Base;1220500]
While deaths from faulty data are tragic, I don't think the format in which you're fighting this "war" is productive, or ethical. Coach's arguement here is passing off that the ACSM/Gatorade are STILL promoting hyperhydration, which just isn't true.[/QUOTE]

Part II

ACSM has not not been swayed by the facts. January of this year, in the latest publication reasonably attributable to ACSM, Samuel N. Cheuvront, PhD, and Robert W. Kenefick, PhD, of USARIEM unveiled a "comprehensive review of dehydration assessment [to present] a unique evaluation of the dehydration and performance literature." Cheuvront S.N. & R.W. Kenefick, [i]Dehydration: Physiology, Assessment, and Performance Effects[/i], January 2014.

USARIEM and ACSM are joined at the hip Sawka-t. As COL K. E. Fiedl, Commander of USARIEM with J. H. Allen, his Chief of Staff, said in [i]USARIEM: Physiological Research for the Warfighter[/i], October 2004:
[indent]>>The influence of USARIEM researchers in the exercise physiology community is highlighted by large representation of our scientists in the professional activities of the American College of Sports Medicine (ACSM), including as senior editor of the primary journal of the ACSM and in the authoring of many of the organizations position statements. [i]Id.[/i], p. 40.[/indent]
[b]Exercise Physiologist Writing Is a Team Sport[/b]

Cheuvront & Kenefick’s comprehensive review has 385 references, some with as many as 12 authors for a total of 1,302 author credits. The authors cited number 899, unique to the first initial (951 unique to the second initial, unfortunately often omitted). The top fifteen authors according to the number of credits, in parenthesis, are Sawka M (29), Cheuvront S (20), Kenefick R (15), Armstrong L (14), Fraser C (13), Montain S (10), Nadel E (10), Casa D (8), Ely B (8), Maresh C (8), Maughan R (8), Adolph E (7), Convertino V (7), Gonzalez-Alonso J (7), Greenleaf J (7). The next five have six credits, and the next 11 have five each. However, these credits are not solo performances (which total 76), but most frequently are partnerships, averaging 3.4 authors per paper. Five references have 10 authors, three have 11, and one has the record of 12. Casa, for example, has written on dehydration eight times, but always with Armstrong.

Cheuvront’s name appears on 20 papers of the 385 reference (which does not incude his comprehensive review), but never alone, and 17 times with Sawka, the most prolific on the subject and the lead author on both Army and ACSM papers. Over half (17 of 29) of Sawka’s papers are partnered with Cheuvront, and 85% of Cheuvront’s papers are written with Sawka. All of this is to observe that Cheuvront has earned credence as a spokesman for ACSM alongside and second only to Sawka.

[b]Cheuvront’s Comprehensive Survey on Dehydration Ignores Overhydration[/b]

Cheuvront (2014) restricts its discussion to dehydration, as promised in its title, but only admits the subject of overhydration through its references. It fails to be comprehensive because it omits the parts of its own references that contradict the ACSM hyperhydration [i]2007 Position Stand[/i], Reference 309. Two examples are Reference 187, Appel (2005), above, with Sawka, and Reference (312), Sawka & Noakes, [i]Does dehydration impair exercise performance?[/i] The latter is an unusual paper, being a debate in two columns with opening statements and responses. Sawka is in the left column, Noakes on the right.

Cheuvront quotes Sawka from #312, Sawka & Noakes, but never Noakes.

In #187 Appel (2005), the summary for water has water intoxication as the lead topic. [i]Hyperhydration[/i] is the first word in the title of three of its sections. It refers to [i]water toxicity[/i] 4 times, and [i]water intox[/i] 22 times, including 17 times in its reference titles.

Cheuvront (2014) does not use the phrases or fragments [i]hyper[/i][-][i]hydra[/i], [i]over[/i][-][i]hydra[/i], [i]tox[/i], [i]poison, [/i]or [i]hyponatremia[/i].

[b]Cheuvront (2014), ACSM's Latest Stand, Fails: It Is Not Comprehensive with Respect to Dehydration[/b]

Cheuvront (2014) omits the 1999 paper by Montain, Latzka, and Sawka, above, that responded to the Army’s bad experience with hyponatremia, which the Army attributed to water intoxication. In the 2014 comprehensive survey, Cheuvront, a member of USARIEM for his professional career, and legitimately a spokesman for ASCM, omits Sawka’s research on the failure of Army regulations to prevent dehydration, and Sawka’s recommendation to replace entirely its 1988 MINIMUMs for water intake with MAXIMUMs, a recommendation adopted by the Army and Marines in 2000.

Thus Cheuvront (2014) is not comprehensive with respect to its subject, dehydration because it omits the Army’s retreat from hydration to prevent dehydration. The ACSM spokesmen have failed to rescue ACSM from its misconduct.

Thanks in large part to the work of Timothy Noakes, reinforced by Army experience, fears over dehydration are obsolete, replaced by the rediscovered dangers of water (Gatorade) poisoning — except at ACSM.

End Part II of II.

Russell Greene 03-07-2014 01:31 PM

Re: Exercise Associated Hyponatremic Encephalopathy, Gatorade and the ACSM
 
Preston,
Our species has drunk water when thirsty since at least 195,000 years pre-Gatorade. Hydration, the activity, is a modern invention. The urge to "hydrate," suggests an effort to consume water at a rate greater than thirst. Hydration can kill.

Gatorade/ACSM advocate the idea that dehydration increases the risk for heatstroke. As usual, this rests on a partial truth. Dehydration has been found to result in a slightly higher temperature. This is not the same as causing heatstroke, however. "Gatoraded physiology," ignores the fact that heatstroke is predominantly a risk during shorter, high intensity activities. Dehydration, in contrast, requires a longer time frame.

Tim Noakes notes in [I]Waterlogged[/I]:
[I]"I was able to trace the reports of 1,939 cases of heatstroke in the literature from 1941 to 2008 in running or other forms of exercise. Of these cases, the majority (1,536 cases) were reported in the militaries of various nations with far fewer numbers in football (predominantly U.S. gridiron) (153 cases) and running (137 cases). The only other large number of cases was reported from the South African gold mines (97 cases). The exercise duration measured as distance run was reported in all but two of the cases of heatstroke in those runners or military personnel who developed heatstroke while running ... Eighty-nine percent of all cases occurred in those who ran less than 20 km; 44% occurred at distances less than 10 km. Remarkably, 10% of subjects developed heatstroke even though they had run less than 5 km. The clear observation is that heatstroke is more likely to occur in those running less than 20 km. Since such a large number of athletes now run marathons each year in different locations around the world, the small number of heatstroke cases in marathon runners cannot be because fewer people run marathons than they do shorter distances. Similarly, the frequency of reported distances that military personnel had marched before they developed heatstroke mirrors that found with the runners: Even when marching rather than running, and hence expending less energy than if they were running, the majority of cases (51%) occurred before the subject had marched even 10 km, and 75% occurred in soldiers who had marched less than 20 km. Thus heatstroke is more likely to occur in exercise of short duration, in which dehydration cannot be a factor (Epstein, Moran, et al., 1999)."[/I]

[QUOTE=Preston Sprimont;1222794]"Under drinking" seems kind of vague, so I guess it depends on how that's defined... but as far as I know, dehydration (do we have a working definition for dehydration for this discussion yet?) can still pose health risks; and, to my knowledge, there is record of injury and death occurring from dehydration. Again, "under drinking" is not defined here; if defined as less hydration than optimal, sure, there's a good chance there's no evidence of injury and death; if defined as less than necessary, however, I imagine we are entering the realm of health-risk-posing dehydration. But I'm not interested in arguing semantics ad nauseum...
My point is this: let's not demonized hydration. Yes, the GSSI and ACSM have skewed, distorted, and butchered the science, seemingly to their benefit, and have disseminated and advertized and pushed this "information" at the expense of the public's knowledge and of some individuals' health. They are in the wrong here. That has been thoroughly demonstrated. However, hydration is not the enemy. Hydration does not threaten the public health or the health of athletes. Super-hydration to the point of hyponatria is the problem. Yes, we all know hydration is important, and maybe that's why it hasn't received much mention here, but I'd hate to see the responses (which are intended to educate and expose) to the GSSI's and ACSM's erroneous claims and falsified science be tainted by error on the opposite end of the spectrum.
If I am in error in claiming that dehydration poses a health risk, and if hydration is in fact an issue, I'm all ears.

Cliff notes: hydrate, but not too much.

Edit/note: I quoted Coach Glassman here because his succinct statement about over- and under-drinking directly addresses what I wanted to comment on, but my comment is a "reply" to many of the quotes in this thread from a number of users that expressed such a sentiment.[/QUOTE]

Preston Sprimont 03-07-2014 03:11 PM

Re: Exercise Associated Hyponatremic Encephalopathy, Gatorade and the ACSM
 
[QUOTE=Russell Greene;1222820]Preston,
Our species has drunk water when thirsty since at least 195,000 years pre-Gatorade. Hydration, the activity, is a modern invention. The urge to "hydrate," suggests an effort to consume water at a rate greater than thirst. Hydration can kill. [/QUOTE]

I agree, the human body has a wonderful way of figuring things out for itself. When you feel thirsty, drink. When you feel satisfied and your thirst is quenched, stop drinking. However, I was using a different definition of hydration than the one you've suggested here--again, whether I like it or not, I guess it comes down to semantics. I do not think hydration suggests drinking beyond thirst. I consider hydration (the noun) as the absence of dehydration, but not to the point of over-/super-/hyper-hydration (that's why we have all those prefixes); and I consider hydration (the verb) to mean the act of preventing or eliminating dehydration by whatever means (just as when one "wets" something, there is the implication that the thing was previously dry).
Now, how the general public defines hydration, I have no idea. So I guess it's good that definitions are being provided here should someone stumble across it.
So yes, with the definition you provided, hydration can be a bad thing--it is essentially defined as an excess, and we have already shown that excess can jeopardize health. We have also shown that Gatprade's advertising implies a similar, unhealthy definition of hydration.
By my definition, hydration is not a bad thing. In fact, it is a good and necessary thing.



[QUOTE=Russell Greene;1222820]
Gatorade/ACSM advocate the idea that dehydration increases the risk for heatstroke. As usual, this rests on a partial truth. Dehydration has been found to result in a slightly higher temperature. This is not the same as causing heatstroke, however. "Gatoraded physiology," ignores the fact that heatstroke is predominantly a risk during shorter, high intensity activities. Dehydration, in contrast, requires a longer time frame.

Tim Noakes notes in [I]Waterlogged[/I]:
[I]"I was able to trace the reports of 1,939 cases of heatstroke in the literature from 1941 to 2008 in running or other forms of exercise. Of these cases, the majority (1,536 cases) were reported in the militaries of various nations with far fewer numbers in football (predominantly U.S. gridiron) (153 cases) and running (137 cases). The only other large number of cases was reported from the South African gold mines (97 cases). The exercise duration measured as distance run was reported in all but two of the cases of heatstroke in those runners or military personnel who developed heatstroke while running ... Eighty-nine percent of all cases occurred in those who ran less than 20 km; 44% occurred at distances less than 10 km. Remarkably, 10% of subjects developed heatstroke even though they had run less than 5 km. The clear observation is that heatstroke is more likely to occur in those running less than 20 km. Since such a large number of athletes now run marathons each year in different locations around the world, the small number of heatstroke cases in marathon runners cannot be because fewer people run marathons than they do shorter distances. Similarly, the frequency of reported distances that military personnel had marched before they developed heatstroke mirrors that found with the runners: Even when marching rather than running, and hence expending less energy than if they were running, the majority of cases (51%) occurred before the subject had marched even 10 km, and 75% occurred in soldiers who had marched less than 20 km. Thus heatstroke is more likely to occur in exercise of short duration, in which dehydration cannot be a factor (Epstein, Moran, et al., 1999)."[/I][/QUOTE]

Thanks for posting that quote. To my knowledge, dehydration and heatstroke are two different things. Often found together, and correlative to each other, but not the same thing, and not causal. This is how I have been considering dehydration in my thoughts and comments.

Christopher Morris 03-08-2014 11:28 AM

Re: Exercise Associated Hyponatremic Encephalopathy, Gatorade and the ACSM
 
[QUOTE=Jeff Glassman;1222795]
[b]Definitional problems[/b]

Exercise physiologists almost exclusively refer to a reduction in body water as dehydration, measuring it as the ratio (percent) of body weight loss, impliedly referenced to some set point corresponding to steady state resting. Other physiologists use [B][I]dehydration to mean a disease with symptoms similar to hyponatremia.[/I][/B] Appel (2005), p. 163. Dehydration symptoms begin with thirst, then progress to include dry mouth, oliguria (low urine volume), dark urine, dry or inelastic skin, orthostatic hypotension (light-headedness upon standing) to syncope (fainting), and to confusion, organ damage, coma, and death. See [i]ICD10, E86.0, Dehydration[/i]; [i]Merck Manual [/i]online.

[b]Sawka Leads the Army To Abandon MINIMUMs for MAXIMUMs[/b]

In fact for a decade, the U.S. Army conducted an experiment with hyperhydration, with disastrous results. Since 1988, the U.S. Army regulations set minimums for water intake. They were “At least ½” quarts/hour in the most benign environment, increasing to “At least 1” quarts/hour, then to “At least 1½” quarts/hour, and finally to “More than 2” quarts/hour. So drinking more than 2 quarts/hour would satisfy all conditions. [/QUOTE]

When I was in the Army I once did five days of field training in Texas in the summer. We were outside in the heat all day doing land navigation, med evac drills, etc. A lot of sweat losses. The drill sergeants encouraged us to drink one canteen of water per hour (one quart or 32 oz per hour). A couple of days into it we were asked to raise our hands if we had followed this recommendation and [I]still[/I] felt symptoms of dehydration, despite drinking as much as recommended. More than half raised their hands. We were told that dehydration can happen even when you drink as much as you "should."

I am now convinced we were actually having symptoms of hyponatremia, not dehydration.

One soldier there passed out during land navigation and was found unconscious by another soldier. He was disoriented and didn't remember where he was or why he was there. He was taken to the hospital and fully recovered. I don't know whether he was following the 1 quart/hour recommendation or not. He may have had hyponatremia or dehydration, as you point out the symptoms can be very similar.

Sean McCue 03-08-2014 11:36 PM

Re: Exercise Associated Hyponatremic Encephalopathy, Gatorade and the ACSM
 
If there are still copies of the book available I would appreciate a copy.

[COLOR="Blue"][I]on the list! ~Lynne[/I][/COLOR]


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