Fisking Repovich and Peterson
A couple of exercise physiologists, Wendy Repovich, Ph.D. and Janet Peterson, Dr.P.H., decided to debunk what they consider the “Top 10 Nutrition Myths,” and did so at the American College of Sports Medicine annual Health & Fitness Summit & Exposition in Dallas, Texas.
Now I’m going to debunk their debunking.
Ah, so many idiots, so little time…
Here goes. And in the order in which they presented them.
10. Eating carbohydrates makes you fat. Cutting carbs from your diet may have short-term weight loss benefits due to water loss from a decrease in carbohydrate stores, but eating carbs in moderation does not directly lead to weight gain. The body uses carbs for energy, and going too long without them can cause lethargy.
The same idiocy that we’ve heard a thousand times recycled once again. Cutting carbs from your diet will indeed bring about weight loss. There is some water loss in the first few days, but once that’s gone most people settle down to a nice, steady loss of fat. How many studies have been published in peer-reviewed scientific papers over just the last couple of years showing that low-carbohydrate diets are more effective than low-fat diets in helping people lose weight? Answer: Many, many such studies. How many studies have there been in this same time showing that low-fat diets are more effective than low-carb diets? Answer: Zero. Conclusion: low-carb diets work better than low-fat diets to help people lose weight.
A rhetorical question: what caloric source is removed from a low-carb diet? Do you think it might be carbohydrates? If so, then when carbohydrates are removed, people lose weight. So, obviously, if carbohydrates are added, people gain weight. It ain’t rocket science, but then again, Wendy and Janet obviously ain’t rocket scientists. But they do have advanced degrees… Makes one wonder.
We could go into all the physiology and biochemistry of insulin resistance and how carbs increase insulin secretion and ultimately insulin resistance in most people, but just the above should be enough to debunk their so-called debunking of the idea that carbs make you fat.
Oh, and the idea that going too long without carbs causes lethargy… Where did these people come from? How many of you on low-carb diets have lethargy? Few I would suggest. In fact, a recurring comment from people following low-carb diets is that they have so much less lethargy. Sorry Wendy and Janet, but it’s an excess of carbs that causes lethargy, not the lack of them.
9. Drink eight, 8-oz. glasses of water per day. You should replace water lost through breathing, excrement and sweating each day – but that doesn’t necessarily total 64 ounces of water. It’s hard to measure the exact amount of water you have consumed daily in food and drink, but if your urine is pale yellow, you’re doing a good job. If it’s a darker yellow, drink more H2O.
I’ll go along with them on this one, although, based on their obviously impaired understanding of biochemistry and physiology, these two would be just the kind of idiots who would say that coffee or tea or any other beverage wouldn’t count as water. It has always amazed me that so many people don’t realize that coffee, tea and all the rest are 99 percent water. If you take a cup of hot water and steep a tea bag in it, does that make the water disappear? No. But you would be stunned at the number of people who apparently believe that it does. “No,” they would say, “tea doesn’t count towards you daily water intake. It has got to be pure water.”
8. Brown grain products are whole grain products. Brown dyes and additives can give foods the deceiving appearance of whole grain. Read labels to be sure a food is whole grain, and try to get three-ounce equivalents of whole grains per day to reduce the risk of heart disease, diabetes, and stroke.
I’ll give a big ‘Who cares?’ to this one. I don’t eat grains, whole or otherwise, so it doesn’t matter to me. If you’re reading this blog, I doubt that it matters much to you. Which means that their advice to “try to get three-ounce equivalents of whole grains per day” to reduce the risk for disease, is pretty much a non-starter. Show me, Wendy and Janet, the well-done studies demonstrating that whole grains reduce the risk of heart disease, diabetes and stroke. Warning: it will be tough to do because these studies don’t exist. While you’re looking for those studies, let me show you a bunch that show that populations forced by circumstances to live on grain-based diets have tooth decay, increased infection, reduced stature, and multiple signs of malnutrition.
7. Eating eggs will raise your cholesterol. This myth began because egg yolks have the most concentrated amount of cholesterol of any food. However, there’s not enough cholesterol there to pose health risks if eggs are eaten in moderation. Studies suggest that eating one egg per day will not raise cholesterol levels and that eggs are actually a great source of nutrients.
This one I agree with whole heartedly, although I doubt that Wendy and Janet would approve of multiple eggs per day. They did throw in the weasel words “eggs in moderation,” which would imply that they felt they were going out on a limb in debunking this particular myth and didn’t want to get too carried away.
6. All alcohol is bad for you. Again, moderation is key. Six ounces of wine and 12 ounces of beer are considered moderate amounts, and should not pose any adverse health effects to the average healthy adult. All alcohol is an anticoagulant and red wine also contains antioxidants, so drinking a small amount daily can be beneficial.
Okay, I’ll cut them a total break on this one. We agree completely. Even with the words “moderate amounts.” I’m not so sure they’re correct on their categorical rationale as to why wine is beneficial, but I’ll go along with them that it is. I’m not so sure, though, that a glass of good single malt scotch wouldn’t provide just as much benefit as the wine. Remember, it has been the wine industry that has funded virtually all of the studies showing that alcohol (i.e wine) is good for us.
5. Vitamin supplements are necessary for everyone. If you eat a variety of fruits, vegetables, and whole grains, along with moderate amounts of a variety of low-fat dairy and protein and the right quantity of calories, you don’t need to supplement. Most Americans do not, so a multi-vitamin might be good. Special vitamin supplements are also recommended for people who are pregnant or have nutritional disorders.
Hmmm. Let’s see if I’ve got this straight. You don’t need them; you do need them; special supplements are recommended. It’s hard to argue with that logic. Here’s how I parse it out. If you follow Wendy’s and Janet’s dietary recommendations, you don’t need supplements. But since most people (probably Wendy and Janet included) don’t follow Wendy’s and Janet’s dietary recommendations, they do need supplements. And anyone who is pregnant or has a nutritional disorder (read: deficiency) absolutely needs supplementation. Well, you’ve got to appreciate how well they debunked that myth.
4. Consuming extra protein is necessary to build muscle mass. Contrary to claims of some protein supplement companies, consuming extra protein does nothing to bulk up muscle unless you are also doing significant weight training at the same time. Even then the increased requirement can easily come from food. A potential problem with supplements is the body has to work overtime to get rid of excess protein, and can become distressed as a result.
Jesus wept. Here we go again with the too-much-protein-is-bad for us mantra. Once again, Wendy and Janet, show me the studies. They can’t because such studies don’t exist. Janet and Wendy are obviously not familiar with the work of Donald Layman, probably the world’s authority on dietary protein (and also a low-carb advocate) who has published extensively on the subject. According to Dr. Layman we need to get at least 7 grams (12 grams is preferable) of the branched chain amino acid leucine to increase muscle growth and optimally regulate insulin function. (Click here for one of Dr. Layman’s papers) Since leucine is found in significant quantities only in meat, eggs, and dairy products, and not in huge quantities even in those, it takes a fair amount of protein to provide the leucine required to build muscle. So, Janet and Wendy, au contraire, it does indeed require extra protein to build muscle mass. And these people are physiologists?
3. Eating fiber causes problems if you have irritable bowel syndrome (IBS). There are two kinds of fiber: soluble and insoluble. Insoluble fiber can cause problems in IBS sufferers; soluble fiber, however, is more easily absorbed by the body and helps prevent constipation for those with IBS. Soluble fiber is found in most grains.
Before we proceed with the debunking debunking, let’s pause just for a minute to enjoy the spectacle of such breathtaking stupidity on display. Consider this sentence: “…soluble fiber, however, is more easily absorbed by the body…” Fiber, whether soluble or insoluble, IS NOT ABSORBED by the body. It shuffles on through the GI tract until it gets to the colon where some of it is converted into short chain fatty acids (that’s right: fiber converts to fat) and absorbed–as fat, not fiber–and the rest is moved on out with the stool.
As to whether or not fiber is harmful for those with IBS, I wrote a fairly lengthy post on this subject last year. The short version is that fiber works to help the stool be pushed along by causing damage to the wall of the bowel. The bowel responds to this fiber-driven injury by producing mucus to help shield the bowel wall from more damage. Mucus makes the lining of the gut more slippery, and the stool slides along a more slippery course, and we are more regular, and the world is great. But the bowel is damaged in the process. So, if you have irritable bowel syndrome do you think it would be good to further damage an already sick bowel lining? I didn’t think so. Sorry Wendy and Janet, but you’re wrong again.
2. Eating immediately after a workout will improve recovery. Endurance athletes need to take in carbohydrates immediately after a workout to replace glycogen stores, and a small amount of protein with the drink enhances the effect. Drinking low-fat chocolate milk or a carbohydrate drink, like Gatorade, is better for the body, as they replace glycogen stores lost during exercise. Protein is not going to help build muscle, so strength athletes do not need to eat immediately following their workout.
Yet again? It takes a scorecard to see where these chicks are coming from.
Myth supposedly debunked:eating immediately after a workout will improve recovery.
I would assume that since they are debunking this myth that the truth (or the truth as they see it anyway) would be the opposite: eating immediately after a workout does NOT improve recovery. But then their very first debunking sentence says that endurance athletes need carbs immediately after a workout. The last time I checked carbs fell into that large category of substances known as food, which is the stuff one eats. So I guess they are saying that endurance athletes need to eat immediately after a workout. Hmmm. They sure debunked that myth.
And what should these endurance athletes eat immediately after a workout? Why, chocolate milk and/or Gatorade, of course. MMM,mmm.
But, God forbid, don’t eat protein. When you work your way through their rickety thinking, what emerges (I think) is that they believe that endurance athletes should eat carbs immediately after a workout but that athletes who are strength training don’t need to eat protein. So the ‘myth’ they are really trying to debunk in their own benighted way is this: eating PROTEIN immediately after a workout will improve recovery.
In this they’re probably right. You don’t need protein immediately after a strength training workout, but you need carbs even less. As you workout, you breakdown muscle tissue and release amino acids back into the amino acid pool. They are reharvested to repair the muscle as needed. But since part of the repair process is to make the muscle larger and/or more dense, extra amino acids are ultimately required. One of the things that stimulates the growth of muscle tissue is the growth hormone released during strenuous training. If you down a high-carb snack or drink immediately after your workout, it is adios growth hormone. Carbs basically shut off the release of this important hormone, so if you’re going to eat immediately after a workout, eat fat and protein. Fat and protein provide the immune support to heal the muscle and provide the raw materials for growth. Last time I checked there wasn’t a whole lot of carbohydrate in the muscle structure.
1. Type 2 diabetes can be prevented by eating foods low on the glycemic index. High levels of glucose are not what “cause” diabetes; the disease is caused by the body’s resistance to insulin. Foods high on the glycemic index can cause glucose levels to spike, but this is just an indicator of the presence of diabetes, not the root cause.
Once again they are both right and wrong. They are right in saying that you can’t prevent type II diabetes by eating foods low on the glycemic index if what you are talking about is carbohydrate-containing foods, which I assume they are. Fructose is low on the glycemic index, but many experts believe that the diabetes epidemic we are now in the midst of is in large part driven by the huge increase in the consumption of high-fructose corn syrup. But I don’t think this is what they are really trying to say. What they’re trying to say is that eating foods high on the glycemic index, i.e. a lot of refined carbs, won’t cause diabetes.
High levels of glucose are not what “cause” diabetes; the disease is caused by the body’s resistance to insulin.
Okay, Wendy and Janet, then tell me what causes the body’s resistance to insulin? Do those of us who have insulin resistance just wake up one morning and discover we somehow developed it in our sleep or is there a cause? I suspect that if you spent more time trolling the medical literature and less time debunking what you consider myths you would learn that carbohydrate consumption does indeed cause insulin resistance in a good many people. For example, studies by Gerald Reavan’s group at Stanford showed that in 75 percent of young apparently healthy subjects carbohydrate intake provoked an increased release of insulin. It follows from that data–since we know that chronically high insulin levels down regulate the synthesis of insulin receptors, and fewer insulin receptors means insulin resistance–that if this 75 percent of subjects were to overeat carbs on an ongoing basis, the odds are that they would ultimately develop insulin resistance. It’s not only Reavan’s studies that imply this. Take a look at this classic paper by Zammit et al; it’s just one of many (I picked it because it’s not loaded with technical language). The evidence is pretty clear: the long-term intake of a high-carbohdyrate diet by genetically predisposed people will cause insulin resistance and type II diabetes. Sorry ladies, but you blew it again.
There you have it. Now don’t you feel better knowing that the influential health-care experts who are giving speeches to large groups of other-health care experts are so knowledgeable about basic physiology and biochemistry. And so well read in the medical literature, to boot.
In an auditorium filled with critical thinkers they would have been booed off the stage.
I have a quick question based on what you wrote here:
In this they’re probably right. You don’t need protein immediately after a strength training workout, but you need carbs even less. As you workout, you breakdown muscle tissue and release amino acids back into the amino acid pool. They are reharvested to repair the muscle as needed. But since part of the repair process is to make the muscle larger and/or more dense, extra amino acids are ultimately required. One of the things that stimulates the growth of muscle tissue is the growth hormone released during strenuous training. If you down a high-carb snack or drink immediately after your workout, it is adios growth hormone. Carbs basically shut off the release of this important hormone, so if you’re going to eat immediately after a workout, eat fat and protein. Fat and protein provide the immune support to heal the muscle and provide the raw materials for growth. Last time I checked there wasn’t a whole lot of carbohydrate in the muscle structure.
I read alot of articles published on T-Nation.com, and they always say it is good to use a drink called “Surge” before,during,and after your workout. If you are not familiar, this drink is high in carbs, but also has some BCAA’s and protein in it. Something doesn’t make sense. Are carbs good or bad after an intense training session? I’ve been under the assumption they are good, but after reading this article, I need some clarification on this.
Thanks,
Scott
Hi Scott–
As I’ve said, the idea of carbs right after a workout is controversial. I need to do some deep reading on the subject. I think the BCAA, especially leucine, will help build muscle, but I’m not so sure about the carb. When I’ve reviewed the subject to my satisfaction, I’ll post on what I’ve found.
Cheers–
MRE
Dr. Eades,
Thanks for the debunking article. I was very worried that people would take the article of Dr. Repovich seriously. I just clicked on the article on MSN because it mentioned Cholesterol and Eggs. Well. We’ve learnt in school, that 1 egg contains 215 mg cholesterol, almost exactly the amount a person can uptake one day. So binging once a week on a huge amount of scrambled egg would be OK, but eat “just” one egg a day would saturate you. Anyway. I gained 8 pounds in the last 3 months eating consciously more carbs. 3 more and I’ll hit 100!
You did not mention that water (around the tea) is necessary for the kidney function. Very necessary. But I am not an expert, just live with guys with kidney stones.
BTW: Dr. Repovich has NO scientific papers on Pubmed. That is the place where everybody (I mean not just scientists or MDs) should look for if he/she mentions science.
I had a prof. who said his wife is pneumologist and she did not believe that smoking would cause lung cancer. Of course she was smoking. Maybe Dr. Repovich is also in denial. I wouldn’t suggest her trying her own diet…
Kornelia M. Szauter, PhD
Hi Dr. Szauter–
I doubt seriously that she follows her own recommendations.
Thanks for writing.
Cheers–
MRE
http://news.yahoo.com/s/nm/20070403/hl_nm/eggs_cholesterol_dc
Reuters has picked up the faux-debunking.
Ha ha never mind. The above was already posted. Sorry doc!
Great blog, very interesting your take on carbs after a workout. Some circles espouse the need for carbs after a workout, I did the 2:1 carbs to protein post-workout shake for the longest time. I felt bloated, the drink felt heavy, for lack of a better word I felt gross.
Hi Vince–
No problem.
The carbs-after-workout idea is a controversial one. I need to bury myself in the medical literature and figure it out. When I do, I’ll post on it.
Cheers–
MRE
Since insulin sensitivity is highest after resistance exercise, it is vital to take a high glycemic index drink immediately after training. This stimulates the secretion of insulin to allow for rapid muscle glycogen resynthesis. Increased fat intake and intracellular triglycerides may cause insulin resistance and hamper muscle glycogen resynthesis. A 2:1 ratio high GI to Whey Isolate protein drink is the current standard for pre and post workout consumption according to current scientific research.
And statins are the current standard for anyone with even minimal elevation of LDL levels according to current scientific research, and I don’t buy that.
Until I see a mountain of evidence that persuades me otherwise I’m sticking to the idea that carbs immediately post workout reduce the production of growth hormone.
Cheers–
MRE
Rather than focusing on insulin response, how about a more direct use for post-exercise carbs?
Exercise uses the stores of glycogen in muscles as fuel. Exercise (especially exercise beyond aerobic capacity) will deplete this. This happens especially in forms where you go to failure, or in marathon-type endurance events.
To retain strength it is ideal to retain glycogen. This is why it is good that fatty acids are released during exercise. The aerobic metabolism picks up, and if you have warmed up, those fatty acids can fuel it, saving the glyogen which can be used for aerobic fuel, for anaerobic fuel. This will allow the glycogen reserves to last longer in exercise surpassing the mitochondrial capacity in cells. This is sort of off-topic though.
As glycogen stores run low (or run out, I’m not sure exactly), gluconeogenesis of amino acids is stimulated. This happens on its own when all tissues are repaired and the amino acid pool is saturated, yes, but it can also happen when there is not an excess of amino acids. I am not sure it is known how depleted glycogen stores must become to avoid this, but it is guaranteed that the best way is to have full glycogen stores.
Some counteract it by taking more protein, to replace the aminos that become depleted. This is a good idea as when you push yourself to the limit some conversion of amino acids will happen occasionally. This is why people take the fast-metabolizing whey or the BCAA post-exercise. Why some take it pre-exercise is usually when they are dieting and want to make sure the AA pool is peaked.
Even so, continually adding aminos like that is expensive and inefficient, why keep replacing glycolized aminos when you can simply replenish glycogen so they will stop getting converted?
That’s probably why I guess. I don’t know about all the insulin-shipping stuff, I agree, confusing literature. I see it as more of a sparing the useful proteins from being broken down into fuel, as well as minimizing unnecessary depletion of the AA pool.
There seemed to be some interest in the book Fiber Menace, mentioned by an earlier commenter. I was intrigued, too, as I love a contrary theory and have had my own suspicions about the pushing of fiber on the public, so I ordered it from Amazon.
I’m only into the introduction and I skimmed through a few topics after looking through the index , but my skeptic flag is already raised on some of the “research” this author has done and the “proof” he provides.
While I understand that he may have an issue with the Atkins advice to drink a lot of water and get enough fiber (perhaps rightfully so), he repeatedly indicates that Dr. Atkins died of heart disease, died morbidly obese, and essentially was a hypocrite. His text and the footnotes indicate that he bases this on what was written in the press. My understanding is that after all these negative press reports, it was revealed that Dr. Atkins’ condition at the TOD was was due to all of the treatment and developments that occurred in the hospital after his head injury due to an accident. IMO, popular press reports are not sufficient “proof” to make such statements, anyway.
To me, this taints his “evidence” quite a bit, so as I read further, I will pay particular attention to the rest of the “evidence”, because it is clear that the author has some bias not based on good info. I can understand that he feels the need to criticize the Atkins and South Beach diets, but attack on Atkins personally seems quite off the mark. I don’t care one way or the other how anyone feels about Dr. Atkins (I’m rather neutral myself), but I do want accuracy and better references than the newspapers and TV tabloids.
So reader beware. Dr. Eades, if you get around to reading this book, I’d love to know your thoughts.
Cheers,
Anna
Hi Anna–
As I mentioned in an earlier comment to a comment, this book is poorly edited, and so, for me, at any rate, a real pain to read. But, I’ll struggle through it and post a review.
I skimmed through it when I got it and saw the same thing you did about Robert Atkins. Dr. Atkins and I have had our issues, but I don’t like to see him lied about in the press or in books quoting press reports. At the time of his death Dr. Atkins had actually lost a fair amount of weight over the previous couple of years. He looked pretty fit and tanned. He fell and hit his head resulting in some pretty severe trauma. I didn’t see Dr. Atkins in the hospital, but I have been involved in the care of many such injuries. One of the mainstays of therapy is large and continuous doses of IV steroids to reduce swelling of the brain. These steroids in the doses required cause fluid retention and a host of other problems. I’m fairly certain (based on experience with other such patients) that at the end he probably had total organ failure (including renal failure) which added to the fluid retention problem. As a result Dr. Atkins gained massive fluid weight in the hospital, which unscrupulous people used to malign him after his death.
The author of The Fiber Menace is supposedly a physician educated in Russia. He says that he went to medical school and graduated with a degree in pharmacology. I don’t know if this means a Ph.D. in pharmacology or that he got an M.D. with special training in pharmacology. At any rate, with his training -whatever it was – he should know better than to rely on press reports to provide accurate medical information.
Having said all that, I will read the book critically and give the guy the benefit of the doubt if he’s come up with anything earth shattering.
Cheers–
MRE
As other posters have mentioned, there are a plethora of articles and the like stating the opposite in terms of carbohydrate intake post workout.
For what it’s worth, after reading this article I decided to just have protein w/ very minimal sugar after my training session the other day. All I can tell you is that instead of feeling strong and lively like I do when ingesting a bit more simple sugar…I felt lethargic for the rest of the day, and found myself sore the next morning. Neither of which have happened for quite some time. In fact I can’t remember the last time either happened.
I’ll try and report back, I believe that there was a study pertaining to this subject that was presented at the last NSCA conference that basically said the sooner the better from what I remember.
As always, I trust the ‘real world’ data you can get from logging everything you do yourself and w/ clients than I do from a guys in white coats who have never picked up a weight in their life.
Hi Russ–
Obviously this is a controversial subject. I’ll look into it deeper and post on my findings soon. I can assure you that although I wear a white coat when I work I have picked up many, many weights in my life.
Cheers–
MRE
According to these sadly misinformed ladies, “Protein is not going to help build muscle, so strength athletes do not need to eat immediately following their workout.”
How moronic is that last statement anyway? It is well-established that one will remain in protein catabolic state when only carbohydrate is ingested after resistance exercise, so traditional sports drinks like Gatorade® are ABSOLUTELY USELESS IN TERMS OF POST-EXERCISE MUSCLE ANABOLISM. In sharp contrast, amino acid ingestion alone significantly increases muscle protein anabolism after resistance exercise. However, consumption of both amino acids and carbohydrate results in much greater effects on muscle protein anabolism, suggesting an interactive effect between insulin, amino acid availability and resistance exercise (1).
It appears that these “exercise physiologists” do not even read ACSM´s own scientific journal Medicine & Science in Sports & Exercise. You see, a paper published in that ACSM journal few months ago also clearly demonstrated the importance of post-resistance exercise protein intake (2). In summary, the intended audience of that presentation was obviously clueless goofs.
Anssi Manninen
References
1. Manninen AH. Hyperinsulinaemia, hyperaminoacidaemia and post-exercise muscle anabolism: the search for the optimal recovery drink. Br J Sports Med. 2006 Nov;40(11):900-5.
2. Cribb PJ, Hayes A. Effects of supplement timing and resistance exercise on skeletal muscle hypertrophy. Med Sci Sports Exerc. 2006 Nov;38(11):1918-25.
Hi Ansii–
Thanks for the comment. I’ll pull the papers you cited and take a look.
Cheers–
MRE
Contrary to claims of some protein supplement companies, consuming extra protein does nothing to bulk up muscle unless you are also doing significant weight training at the same time.
Actually, even this statement by Repovich and Peterson may be false.
The study Effects of leucine and whey protein supplementation during eight weeks of unilateral resistance training by
Coburn JW, Housh DJ, Housh TJ et al. . [J Strength Cond Res, 2006;(2):284-91.] found that leucine supplementation with whey protein resulted in increased muscle volume even in muscles that were not trained.
For the laymen, here’s a summary:
http://findarticles.com/p/articles/mi_m0KFY/is_9_24/ai_n16820648
Hi John–
Thanks for the article citation. I hadn’t seen that one. Run a PubMEd search on Layman DK to find a number of other good studies on BCAA in general and leucine in particular.
Cheers–
MRE
Thanks for the reply.
Quick question (but only if you’re not feeling swamped!): My layman’s reading of the abstract seemed to indicate that in those on the leucine+whey combo, not only did some of the untrained muscles grow in size and strength, but they grew as much as the trained muscles. That result seems even more far-fetched.
Am I misreading the (rather technical) language, or could such a thing be possible?
Hi John–
In my reading I interpret it to mean that there were significant changes in both, but not necessarily the same. I’ve got the paper on order through interlibrary loan (unfortunately my university doesn’t subscribe to that particular journal so I don’t have immediate access to an electronic version); I’ll be able to glean more from the paper than from the abstract.
Best–
MRE
I came across another interesting study that might represent a possible explanation for the growth of the untrained leg in the Journal of Strength and Conditioning Research article.
The new study found that the expression of the Myostatin gene (which limits muscular growth) was reduced by 37% in subjects who participated in high-intensity resistance exercise.
Myostatin Gene Expression Is Reduced in Humans with Heavy-Resistance Strength Training
http://www.ebmonline.org/cgi/content/full/228/6/706
“A 37% decrease in myostatin expression was observed in response to [strength training] in all subjects combined.”
Is it possible that the expression of the myostatin gene is further mediated by the amount of protein vs. carbohydrate ingested? (The controls in the leucine & whey experiment had shakes that contained maltodextrin in place of the leucine and whey.)
Thanks for a great blog, Dr. Eades!
Hi John–
Interesting paper. I don’t know if the subjects in the paper on leucine and whey did enough heavy-resistance strength training to decrease their myostatin expression. But I don’t know for sure. I find the whole myostatin issue pretty interesting, however. Doug McDuff, M.D. (who trained at Arkansas where I did my medical training), and who promotes a slow motion type of resistance training similar to Slow Burn, has written a good general article about myostatin that you can find on his website. You have go there, navigate to ‘Articles’ and look for the following: Muscle: The Myostatin Connection.
I suspect that the leucine works in a different direction, however. It seems to work through a particular signaling cascade involving insulin to stimulate muscle growth.
Cheers–
MRE
Can you summarize in 2-3 sentences (you probably don’t even need that many!) something on what I believe is the myth about LC diets and “acidic blood.” That LC makes the blood acidic. I know there was a recent study that found that LC didn’t cause bone loss or bone ??turnover, and that calcium leaching relates to the acidic blood situation.
I participate on a non-nutrition blog where LC is getting trashed, and I am trying to hang in there in the arguments with the little science I know. I can’t find any googles debunking “acidic blood on LC,” however.
I am thoroughly enjoying past posts of yours. Unbelievable stuff. Thank you for enlightening all of us.
Jill
Hi Jill–
Two or three sentences, eh?
A number of foods cause an increase in acidity of the blood: cheese, grains, and meat are the primary ones. Other foods cause just the opposite: a decrease in acidity in the blood. These anti acidity foods are green leafy and colorful vegetables and many fruits. The total acidity of the blood is a function of the total composition of the diet, so if you eat meat, avoid grains, and consume green leafy and colorful vegetables, your blood acidity should be as it should.
Having written these couple of sentences, I must add that Herta Spencer, one of the world’s foremost calcium experts, has done a number of studies showing that a large amount of protein in the diet does NOT cause a decrease in calcium in the urine, which means that the increased protein does NOT cause calcium to be leached from the bones. I have spoken directly with Dr. Spencer on this issue, and she assured me that all of her work bears this out.
This is probably a topic for a blog post. Hope these few sentences help.
Cheers–
MRE