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February 27

Does mild sleep apnea boost athletic performance?

Russia is now suspected of having let its athletes use Xenon gas to boost atheletic perforamance of endurance athletes for about a decade. Apparently, if you inhale Xenon gas some time after exercise, then the shortage of oxygen will lead the body to produce more EPO and perhaps there are other effects that will boost the body's ability to transport oxygen better to the muscles. When I read about this, I was thinking that perhaps sleep apnea exists because it actually has similar beneficial effects. Of course, the severe sleep apnea is not going to be beneficial. But many people who in later life become sleep apnea patients would already have had mild sleep apnea when they were much younger without having had symptoms. Count Iblis (talk) 14:05, 27 February 2014 (UTC)

Well, sleep apnea is highly concentrated in people who are severely overweight. That fact doesn't seem to accord very well with your ideas. Looie496 (talk) 14:41, 27 February 2014 (UTC)

It has nothing whatsoever to do with sleep apea. Since xenon is an inert gas, it cannot participate in any body metabolism process, and breathing it is the same as reducing the oxygen and nitrogen partial pressure - the same as living at high altitude, which is well known to give improved oxygen delivery to tissues when you return to low altitudes. An interesting solution, as no test can be devised for something that cannot participate in chemical/enzymatic reactions, and living/training at altitude is a perfectly legal way to improve athletic performance. And done at reasonable concentrations, at cannot harm you, not in the short term and not in the long term, very different to performance boosting drugs, which are banned partly due to their adverse effects on long term health. 121.221.210.239 (talk) 14:50, 27 February 2014 (UTC)

But the trainers who are partial to this training method will feel the pressure to constantly improve, increasing the amount of xenon, until they cause brain damage or death in the athletes. StuRat (talk) 15:02, 27 February 2014 (UTC)

Come on guys! At least look it up first! The protocol described involves breathing a 50-50 oxygen-xenon mixture for minutes before going to sleep. [1] Besides, if xenon's action were just as an inert gas, you'd expect they'd use argon, which is cheaper and more common. Xenon is the least "inert" of the inert gases, and so I wouldn't rule out a drug-like effect... it'll be worth looking into further. Wnt (talk) 16:03, 27 February 2014 (UTC)

Note that the sources (including your one) also mention that effects may also last 48-72 hours and that such treatment may be better than a low oxygen environment (although it's not clear to me how well tested this is in humans) which as the sources mention, is also used to basically simulate a high altitude environment. Nil Einne (talk) 17:50, 27 February 2014 (UTC)

Would mild sleep apnea have a similar effect? Count Iblis (talk) 18:26, 27 February 2014 (UTC)

Dunno. The body actually produces more RBC's at altitude and is why Mt. Everest climbers spend a few weeks at base camp prior to climbing. RBC's can double in a few weeks at altitude. Is there any RBC studies of apnea patients? Apnea seems to be only a sleep related issue so I kind of doubt it would have a measurable effect on RBC count. Xenon/oxygen therapy seems more like what scuba divers would use to extend dive times. Is it also hyper- or hypo-baric? Divers use specialty gases to extend dive times and avoid the bends. See Breathing gas. I suspect the high concentration of oxygen relative to xenon is done in a pressure chamber and the relatively high molecular weight of Xenon prevents it from turning into bubbles at low pressure (and the bends). Oxygen helps the athlete recover faster. Just guessing though from my experience with Scuba and the "1 hour 50/50 mix" answer. Too much oxygen is toxic so that often limits dive depths (the pressure in the lungs equals the depth pressure, but that increases the amount of oxygen molecules - specialty gas mixes usually don't increase depth but do increase time at a shallower depth before the bends are an issue). It sounds like they are increasing the amount of O2 without overloading the system with gasses that will outgas at low pressure. --DHeyward (talk) 04:55, 28 February 2014 (UTC)

A similar effect to what? An oyxgen tent aka stimulating a high altitude environment or breathing a mixture of xenon and oxygen? As we have established, there's some evidence these don't seem to be the same thing. BTW, I was reminded yesterday of something else, I researched euthanasia before for the RD (mentioned twice, look in the archives) and seem to recall coming across xenon or argon or both. Some more quick searches now find [2] which discusses the anaesthetic and neuroprotective effects of xenon. [3] suggests it may also have cardioprotective effects. This discusses other effects [4]. If you look at the links and refs, it sounds like there are lot more recent studies like [5]. This [6] interestingly suggests that argon and xenon are different under normobaric conditions with argon lacking such an anaesthetic effects. Some more here [7] [8] [9] (this BTW suggests argon may also be useful for enhancing athletic performance). Most of these are not in humans (although some of them were) and they may not necessarily be relevant to how xenon or argon may improve athletic performance. But they do IMO further emphasise it's likely a mistake to simply treat is as equivalent to a lower oxygen concentration.

Nil Einne (talk) 16:17, 28 February 2014 (UTC)

A sidetrack about using this mixture therapeutically finds [10][11][12][13]. Most of these applications are very recent, so I am indeed intrigued by the possibility that this means it could be used even for cases like the optic nerve degeneration that was discussed a week or so ago,^[14] to reduce ischemic damage even after the fact. What makes xenon special is that it is an inhalational anaesthetic, which is still as they say "a great mystery". There are some really peculiar results on the topic if you look into it. Wnt (talk) 16:34, 28 February 2014 (UTC)

Edit: I belatedly found [15] which also looks useful. Note that from what I saw (I didn't read that well), I don't think there's much of a suggestion of any chemical reactions. However it sounds like some of them may bind to active sites (including I think myoglobin) or otherwise have effects in biological systems, sometimes resulting in upregulation or downregulation in living systems. Stuff such as lipid solubility, permeability, molecular weight and other factors seem to play a part in their effects. Nil Einne (talk) 16:53, 28 February 2014 (UTC)

Just spotted [16] which suggest (obstructive) sleep apnea increases the red blood cell distribution width, which is a sign of ineffective red blood cell production. It appears more or less unrelated to erythropoietin. [17] Erythropoietin may be useful to treat it. [18] Then again, erythropoietin does seem to be involved in the less common central sleep apnea [19] where it can have a pathological effect on heart failure. Using apnea while awake for sports training was an idea in Med Hypothesis [20], which in my book puts the odds against it! Basically, because if a hypothesis has any support, or any way of getting support, it doesn't get published in Med Hypothesis... :) Wnt (talk) 16:44, 28 February 2014 (UTC)

Thanks everyone for your information/comments! Count Iblis (talk) 01:38, 3 March 2014 (UTC)

Alkalizing foods question

Below is a quote from the webpage: http://www.alkalizingforlife.com/page/page/5128908.htm

"The following lists go over the acid or alkaline values of the foods we eat. The accurate way to measure the alkalinity of food is how the food changes the pH value of the tissues of the body. Once food is digested, an "ash" is formed. The pH of this ash is different than the pH value of the actual food itself. Lemons for example are very acidic by themselves however when digested they have an alkalizing effect in the body!"

This is accompanied by a list of dozens of foods in the seven categories: highly alkalizing, moderately alkalizing, low alkalizing, neutral, low acidic, moderately acid, highly acidic.

Just to give a few examples, sea salt is rated as "highly alkalizing" and table salt as "highly acidic". Celery as "highly alkalizing". Bacon as "highly acidic".

My questions:

1) Is an "ash" formed when a food is digested by a human?

2) Is there any possible way that the pH of such ash could be measured in the human body? or after elimination from the body?

3) Is the webpage pure nonsense or is there some truth to what it says?

Thanks, CBHA (talk) 23:37, 27 February 2014 (UTC)

Complete nonsense. See Alkaline diet or http://rationalwiki.org/wiki/Alkaline_diet --Carnildo (talk) 02:44, 28 February 2014 (UTC)

The article makes a clear case that there is some pseudo-science about it, but the main confusion concerns whether it is the blood or the urine one is trying to alkalize. I think it's pretty mainstream science that acidic urine is a recipe for specific troubles in the excretory system, and herbalists cannot be blamed for viewing a diet that might avoid the need for a specific medication to alter pH as being a generally desirable thing. Using it to treat cancer, of course, sounds like very wishful thinking. But anyone who has ever seriously thought about what getting a kidney stone is going to feel like should have a keen appreciation of alkalinity. Wnt (talk) 02:59, 28 February 2014 (UTC)

(ec) Alkalizing foods are most relevant to gout and many kidney stones, in which the goal is to raise urine pH to increase the solubility of uric acid and clear it from the body. [21][22] Studies like this show that urine pH can be manipulated by this means. It is more common to prevent problems with potassium citrate, a commonly prescribed drug that is also a GRAS food component, which may benefit some unexpected populations. [23] In a pinch, magnesium citrate ought to have a similar effect and is an easily found nutritional supplement. However, of course, one can imagine that the healthy vegetables on the list have many benefits. I do have a hard time seeing how salt enters or leaves as anything but Na+ and Cl-; however, the network of ion pumps in the kidney is quite complex, and I'd really have to think carefully about whether there is a way that changing the overall amount of these ions passing through would affect the net flux of bicarbonate (versus exhalation of carbon dioxide) Wnt (talk) 02:51, 28 February 2014 (UTC)

Hmmm, just searching, it looks like KCl can actually raise urine pH [24] The relationship between salts and urine pH is complex -- see [25]. sodium and hydrogen, chloride and bicarbonate, they are all tied together in a network of exchanges that is also actually regulated by the body with paracrine associations between the distal and the proximal loop of the kidney.

I still think the bottom line, though, is that the body has the same potential control over pH as limestone. When raw limestone is dumped in water, it has only a very mild alkalizing effect against acid rain, but when it is heated to drive off the CO2, it turns into a caustic calcium oxide. The body has the same sort of range of opportunities -- it can process food to CO2 that is exhaled, or allow that CO2 to remain part of the overall composition of the urinary fluid as (in net composition) carbonic acid. (see [26] for an overview) So this is a regulated phenomenon that has to be studied empirically; the body isn't a test tube that can be counted on to passively reflect an average of what is dumped into it. Wnt (talk) 03:19, 28 February 2014 (UTC)

"I think it's pretty mainstream science that acidic urine is a recipe for specific troubles in the excretory system," - this is incorrect. Acid urine prevents urinary tract infection (UTI) and acidification of the urine is one of the major ways of preventing it. Typically accomplished with aspirin. — Preceding unsigned comment added by AboutFace 22 (talk • contribs) 00:02, 3 March 2014 (UTC)

Well, alright, I should have mentioned that alkaline urine is a recipe for specific other troubles in the excretory system!  :) After all, the range of values urinary pH can have should be a fair reflection of what values just plain work out best. And I am not accepting that an alkalizing diet is a desirable food choice for anyone - just for some people. Wnt (talk) 19:55, 3 March 2014 (UTC)