Monday, April 7, 2014

Glycogen and Water Weight

One regularly hears that when one goes on a low-carb diet, one loses glycogen, and the weight loss is due to the fact that glycogen is stored with water, so the weight one loses is due to the water lost with the glycogen.

"Glycogen losses or gains are reported (2) to be associated with an additional three to four parts water, so that as much as 5 kg weight change might not be associated with any fat loss."
Here's that footnote:
2. Olsson K. Saltin B. Variation in total body water with muscle glycogen changes in man. Acta Physiol Scand 1970:80: 1 1-8.
From here:
"Glycogen storage: illusions of easy weight loss, excessive weight regain, and distortions in estimates of body composition."
Interesting. How did they get to that number?
"The total body water increased 2.2 1 which is assumed to be caused by the glycogen storage in the muscles and the liver. The amount of glycogen stored was calculated to be at least 500 g, which means that 3—4 g of water is bound with each gram of glycogen."

"Variation in Total Body Water with Muscle Glycogen Changes in Man"

Emphasis mine. Wait, they assumed? Has anyone checked this?
"Muscle water content expressed as mumol H2O lost/g wet tissue weight or made relative to protein content showed no consistent relationship to the glycogen content. These data, therefore, do not support the commonly accepted muscle glycogen-to-water ratio of 1.0:2.7 (g:g). Further work is necessary to quantify the exact amount of water that is actually associated with the glycogen complex."

"Muscle glycogen storage and its relationship with water."

And here:
"The extent to which muscle glycogen concentrations can be increased during exposure to maximal insulin concentrations and abundant glucose was investigated in the isolated perfused rat hindquarter preparation.... Total muscle water concentration decreased during glycogen loading of the muscles."

"Mechanisms limiting glycogen storage in muscle during prolonged insulin stimulation"

I can't find any evidence that anyone's tried to confirm this assumption in man.

An assumption does not equal knowledge. It's a guess, however educated. And a guess is not "science".

I do think, however, that body weight can go up with glycogen increase. But the water's not in the muscles, it's in the gut, buffering the sugar that is generally used to replenish muscle glycogen:

"What he discovered was that if he drank sugary water, his body reacted to it by flooding his stomach with water.

"...Two lights went on over my head on hearing this. The first is that this explains diabetics’ frequent thirst and urination: they’re thirsty because diabetics consume a lot of sugar, which requires their bodies to dump water into their guts. They need to replenish this water in their systems, and perhaps drinking the water helps in diluting the sugar in their guts."

And going on a low-carb diet allows the body to lose the water that's in the gut (doing you no good from a running performance perspective), not the muscles.

At least that's n=1, not n=SWAG.

[Scientific Wild-Ass Guess] P.S. OK, it's not just me: "...Several attempts have been made to estimate the amount of water stored in muscle in association with glycogen, but this is not easily quantified. Early data suggested a value of about 3 g of water for each gram of glycogen (Olsson & Saltin, 1970). However, a subsequent study by Sherman et al. (1982), in which the muscle glycogen content of rats was manipulated by exercise and diet, suggested that there was no consistent association between the amount of glycogen stored in a muscle and the muscle water content. Richter, Hansen, and Hansen (1988) found a decrease in muscle water concentration after muscle glycogen loading. Nygren, Karlsson, Norman, and Kaijser (2001) have also suggested that glycogen loading may alter the disposition of water molecules within the muscle. These apparently conflicting data may result from different amounts of water storage with different structural forms of glycogen and changes in the proportions of these different forms as the total amount of glycogen changes. "Notwithstanding the uncertainties, there is good evidence of gross changes in body mass as a consequence of diet and exercise manipulations designed to induce alterations in glycogen storage in humans. Any major change in the amount of glycogen stored in muscle will result in a change in body mass, with the major part of the mass change being a consequence of the storage of the associated water (Olsson & Saltin, 1970)...." The studies they cite are the studies linked to above. They're not particularly logical with that last statement, however, as there's still no evidence for the proposition that glycogen is stored with water. But that's how scientific myths stay alive!

Thursday, March 27, 2014

"Animal Fibre"

I like reading things that make me smack my forehead and think, "You idiot: why didn't you think of that!"

This is one of those posts:

Fruits and veggies, fermented or otherwise, aren’t the only source of prebiotics in your diet. Eat a whole sardine and some of the ligaments, tendons, bones, and cartilage will surely escape digestion to reach the distal intestine where they will be fermented by the resident microbes.
Read the whole thing, but this explains why populations that don't eat much or any plant fiber, like the Maasai warriors or Eskimos of yore, do perfectly fine.

Monday, March 24, 2014

Doctors and Public Health

Still true today:
"A certain section of medical opinion, in late years, has succumbed to the messianic delusion. Its spokesmen are not content to deal with the patients who come to them for advice; they conceive it to be their duty to force their advice upon everyone, including especially those who don't want it. That duty is purely imaginary. It is born of vanity, not of public spirit. The impulse behind it is not altruism, but a mere yearning to run things." — H.L. Mencken
In their role in society, medical doctors have replaced priests to a large extent.

Tuesday, March 4, 2014

Is Science Broken? Part 9: Yes

Really no other way to summarize this post at In the Pipeline:

"Sydney Brenner on the State of Science":'s an outspoken interview with Sydney Brenner, who's never been the sort of person to keep his opinions bottled up inside him. Here, for example, are his views on graduate school in the US:

Today the Americans have developed a new culture in science based on the slavery of graduate students. Now graduate students of American institutions are afraid. He just performs. He’s got to perform. The post-doc is an indentured labourer. We now have labs that don’t work in the same way as the early labs where people were independent, where they could have their own ideas and could pursue them.

The most important thing today is for young people to take responsibility, to actually know how to formulate an idea and how to work on it. Not to buy into the so-called apprenticeship. I think you can only foster that by having sort of deviant studies. That is, you go on and do something really different. Then I think you will be able to foster it.

But today there is no way to do this without money. That’s the difficulty. In order to do science you have to have it supported. The supporters now, the bureaucrats of science, do not wish to take any risks. So in order to get it supported, they want to know from the start that it will work. This means you have to have preliminary information, which means that you are bound to follow the straight and narrow.


Here are Brenner's mild, temperate views on the peer-review system and its intersection with academic publishing:

. . .I don’t believe in peer review because I think it’s very distorted and as I’ve said, it’s simply a regression to the mean.

I think peer review is hindering science. In fact, I think it has become a completely corrupt system. It’s corrupt in many ways, in that scientists and academics have handed over to the editors of these journals the ability to make judgment on science and scientists. There are universities in America, and I’ve heard from many committees, that we won’t consider people’s publications in low impact factor journals.

Now I mean, people are trying to do something, but I think it’s not publish or perish, it’s publish in the okay places [or perish]. And this has assembled a most ridiculous group of people. I wrote a column for many years in the nineties, in a journal called Current Biology. In one article, “Hard Cases”, I campaigned against this [culture] because I think it is not only bad, it’s corrupt. In other words it puts the judgment in the hands of people who really have no reason to exercise judgment at all. And that’s all been done in the aid of commerce, because they are now giant organisations making money out of it.

I don't find a lot to disagree with there, either.

The point of academic Science is to provide jobs for academics. Any "science" that occurs is a happy coincidence, in large part.

Thursday, January 30, 2014

Altra: "Local Shoe Company Reaches Global Market"

Very cool!:

"...Instead of resorting to running in “high heels” as he called them, [Golden] Harper “zero-dropped” his shoes by cutting the heel elevation out of them. “It was effortless,” Harper said. “I had shoes on but I ran naturally like I was barefoot! I wanted everyone to feel that feeling of being able to run natural.”

"Harper and some of the employees at the store started cutting shoes flat for people to try at their running store, and within months, more than 1,000 people had paid the local shoemaker $20-$60 to cut the heel elevation out of their shoes.

"Harper knew he had something great and set out to create and market what he had named Altra Zero Drop, stemming from the innovation of “AL-tered shoes” and his love for ul-TRA marathons.

"The shoes had a foot-shaped toe box for more room in the front, as well as a cushioned, zero-drop sole.

"However, after proposing the concept to several companies that showed no interest, he spoke to his cousin, Jeremy Howlett. “Let's just do it ourselves," Howlett told him...."

And they did. Thanks to Zach Bitter on Twitter:

Saturday, January 18, 2014

A Plague of Doctors

My title is more appropriate than the one the New York Times offers: An Epidemic of Attention Deficit Disorder, since the point of their editorial is that the "epidemic" they're discussing doesn't actually exist, but has largely been manufactured by predatory drug companies and compliant or ignorant doctors:

"...A two-decade campaign by pharmaceutical companies promoting the pills to doctors, educators and parents was described by Alan Schwarz in The Times on Sunday. The tactics were brazen, often misleading and sometimes deceitful. Shire, an Irish company that makes Adderall and other A.D.H.D. medications, recently subsidized 50,000 copies of a comic book in which superheroes tell children that “Medicines may make it easier to pay attention and control your behavior!” Advertising on television and in popular magazines has sought to persuade mothers that Adderall cannot only unleash a child’s innate intelligence but make the child more amenable to chores like taking out the garbage.

"The potential dangers should not be ignored. The drugs can lead to addiction, and, in rare cases, psychosis, suicidal thoughts and hallucinations, as well as anxiety, difficulty sleeping and loss of appetite. On Tuesday, the Food and Drug Administration warned that some A.D.H.D. medications, including Ritalin, Concerta, and Strattera, may, in rare instances, cause prolonged and sometimes painful erections known as priapism in males of any age, including children, teens and adults.

"So many medical professionals benefit from overprescribing that it is difficult to find a neutral source of information. Prominent doctors get paid by drug companies to deliver upbeat messages to their colleagues at forums where they typically exaggerate the effectiveness of the drugs and downplay their side effects. Organizations that advocate on behalf of patients often do so with money supplied by drug companies, including the makers of A.D.H.D. stimulants. Medical researchers paid by drug companies have published studies on the benefits of the drugs, and medical journals in a position to question their findings profit greatly from advertising of A.D.H.D. drugs.

"The F.D.A. has cited every major A.D.H.D. drug, including the stimulants Adderall, Concerta, Focalin and Vyvanse, for false and misleading advertising since 2000, some of them multiple times. The companies, when challenged, typically stop those misleading claims, but the overall impact appears marginal. The number of prescriptions for A.D.H.D. drugs for adults ages 20 to 39 nearly tripled between 2007 and 2012, and sales of stimulant medications in 2012 were more than five times higher than a decade earlier.

"Curbing the upsurge in diagnoses and unwarranted drug treatments will require more aggressive action by the F.D.A. and the Federal Trade Commission, which share duties in this area. It will also require that doctors and patients recognize that the pills have downsides and should not be prescribed or used routinely to alleviate every case of carelessness, poor grades in school or impulsive behavior."

Millions of children, mostly boys, are on these drugs for no good reason. The difference between this and the old snake-oil salesmen is that snake oil was ineffective, but had no side effects. It was a simple fraud. This is malpractice on an industrial scale.

Patients need to realize that First, do no harm is no longer a directive for the medical profession, and perjury, the breaking of an oath, is no longer considered a crime.

"I will apply, for the benefit of the sick, all measures [that] are required, avoiding those twin traps of overtreatment and therapeutic nihilism."

Your only protection is your own diligence. Buyer beware.

Thanks to Seth Roberts.

Thursday, January 16, 2014

"What Ultra-Marathons Do to Our Bodies"

Very little, apparently, except make us healthier than average.

"...Hoping to better understand what happens to an ultra-endurance athlete’s body, researchers at Stanford University and the University of California, Davis recently contacted more than 1,200 experienced ultra-marathon runners and asked them probing and almost impolite questions about the past and current states of their bones, hearts, blood pressures, prostates, breasts, skin, lungs, moods, bowels, eyes, waistlines, livers and many other body parts and systems. They also asked about their race histories, times, training regimens and any recent injuries and illnesses....

"...And there can be substantial, accruing benefits to covering those miles, says Dr. Eswar Krishnan, an assistant professor at Stanford and co-author of the new study. Over all, the ultra-runners in the study were absent from work less often than other American adults because of illness or injury, he said, and rarely felt compelled to see a physician, with almost half visiting a doctor only once in the past year, usually because of a running injury.

"Of course, the ultra-competitors may have “developed stoicism” from their many hours of training, Dr. Krishnan said, and ignored niggling ills that would keep the rest of us from work or send us hurrying to the doctor. But they also displayed a substantially reduced risk of developing many of the common diseases of modern life...."

No surprise to me. This is what we evolved to do.

From the study:

The present work provides an analysis of medical issues in a large cohort of ultramarathon runners. As expected, the work demonstrates that, with the exception of asthma and allergies, ultramarathon runners have fewer chronic medical conditions than the general population, tend to miss little time from work or school due to illness or injury, and make limited use of the medical care system.

So go run. I'll note that most of the injuries they describe could be reduced with a barefoot-style running form...