|Nutrition discussion on Nutrition Roundtable, within the Bodybuilding Forum; Bodybuilder Nutrition Roundtable Interview Conducted by Josh Beaty The following interview was conducted by Josh Beaty with Layne Norton, Jamie ...|
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|01-26-2007, 07:35 AM||#1|
| EricT |
Experience: 7-10 Years
Join Date: Jul 2005
Bodybuilder Nutrition Roundtable
Interview Conducted by Josh Beaty The following interview was conducted by Josh Beaty with Layne Norton, Jamie Hale, Alan Aragon and Will Brink. Sit back and enjoy a very informative discussion.
The mTOR Pathway
J Beaty: The big focus in hypertrophy research lately has the mTOR pathway. What impact does this research have on bodybuilders?
L Norton: The mTOR pathway is a major cellular anabolic pathway that is responsible for much of the anabolic response to nutrient stimulus. In adult subjects, amino acids (specifically leucine) are responsible for triggering mTOR activation. mTOR essentially acts as a 'leucine gauge.' If leucine levels increase, mTOR becomes active & activates other components of the protein synthetic pathway because high leucine levels indicate a fed state, and ample amino acids are present
for protein synthesis to occur. If leucine levels drop, mTOR becomes less active as it senses that there are not enough amino acids and energy to continue protein synthesis. mTOR is also sensitive to total energy intake and if total energy drops too low, then mTOR becomes less activated. This research indicates what many bodybuilders have known for sometime: if your goal is to build muscle mass, make sure you provide a diet with ample calories and ample amino acids.
W Brink: I'm not going to have a great response to this question as it's really not my area of focus or expertise. As far as I know, there is no practical application of the mTOR pathway to athletes at this time. That is to say, I don't know of any particular change an athlete can make to their approach that will profoundly alter this pathway to give any advantages. It may also simply be that the approach we know is optimal for strength and or LBM - loading, volume, tempos, etc - are already the best we can do as far influencing mTOR is concerned. Like so many areas of research that may have applications to wasting diseases and such, such as myostatin, it's more of an intellectual exercise versus having any real practical application to athletes at this time, non-pharmacologically speaking at least. There is no doubt that the intensive research going on that examines the signaling events that are activated by aerobics or resistance training will explain how muscle adaptations take place, and pharmaceutical interventions are a focus of many researchers, but I am unaware of any direct application an athlete can incorporate in their training or diet that will be an improvement on what we already know. The other guests on this roundtable may be more up to date on the literature and have a better answer! I'm a bit jaded at this point in that I don't get particularly excited or interested in the latest holy grail of signaling molecules until some real practical application shows itself.
J Hale: The mammalian target of rapamycin (mTOR) is a serine/threonine kinase that plays a key role in anabolism. mTOR stimulates cell growth by phosphorylating p70 ribosomal S6 kinase (S6K) and eukaryote initiation factor 4E-binding protein 1 (4EBP1). mTOR is stimulated by resistance training, insulin and leucine (BCAA). When mentioning the mTOR pathway it is probably necessary to mention there are also other kinases that inhibit anabolism when activated. In particularly I am referring to the AMPK/Akt mTOR switch. Basically when AMPK is elevated protein synthesis is inhibited. AMPK (5’-AMP-activated protein kinase) is a heterotrimeric serine/threonine kinase. AMPK is often referred to as a cellular fuel gauge. AMPK is activated by endurance exercise, elevated levels of cellular AMP, hypoxia, glucose deprivation and ischemia. When AMPK is elevated cellular fuel regeneration is top priority, while pathways that consume energy are inhibited (ex: protein synthesis). This applies to athletes as we know various conditions stimulate these pathways. By optimizing stimulation of anabolic pathways and minimizing catabolic pathways (intensity and duration of) we obviously optimize performance and physique benefits. Does this really tell us any more than we already knew (proper resistance, protein intake and sufficient cals maximize growth)? For myself and other practical scientists I feel like this info is very helpful with enhancing our knowledge of what’s going on at a cellular level. It also helps with program design and recognizing, at a molecular level, factors that affect anabolic and catabolic pathways. As far as the typical bodybuilder or trainee is concerned, knowledge of mTOR pathway may or may not be beneficial. Depends on the bodybuilder and how serious he is about furthering his knowledge concerning physique and performance.
A little off the subject alcohol intoxication has also been shown inhibit the mTOR pathway. Studies involving the mTOR pathway also are important in treating muscle wasting disease.
A Aragon: First off, I’d like to thank Jamie for inviting me to this roundtable. It’s definitely an honor to be among a carefully chosen few. If I come off too long-winded in this, it’s because I made Jamie wait for months for me to participate, so I figured I might as well show some gratitude and babble for eons.
Ah, the good ol’ phosphatidylinositol 3-kinase-mammalian target rapamycin signaling pathway. There, that should take care of any lack of technical jargon I contribute to this roundtable right off the bat. mTOR research is not likely to have a significant impact on the furthering of what bodybuilders can physically achieve, but it certainly is giving us some understanding of how these achievements occur. Let’s face it, the majority of the biggest, most ripped guys on the planet haven’t even heard of mTOR.
The first thing most folks think about in relation to mTOR and bodybuilding is leucine, and rightly so, since leucine phosphorylates/activates the downstream metabolites of mTOR. But alas, there’s a caveat. A lot of folks who place an excessive focus on leucine will indiscriminately dose the hell up on it. They’ll tank down isolated leucine, BCAAs, and/or whey, thinking they’ve found the ticket to net anabolism. There’s also this false implication that whey, being higher in leucine than casein, is superior. Not true, at least according to the current body of research, which indicates that casein, or at the very least, a blend of casein and whey, is superior to whey alone for affecting a number of parameters bodybuilders care about.
What people seem to constantly forget is that net gains in muscle are the result of not just protein synthesis, but the inhibition of protein breakdown. Casein’s anti-proteolytic effect is more profound than whey or leucine’s protein-synthetic effect - hence, its lead spot in the current body of research. The name of the game seems to revolve back to the old cliché of mixing things up, and achieving a variety of sources of protein from whey to casein, to flesh, to the range of sea and land flesh, to Asian women. Just kidding, I wanted to make sure everyone was awake. In sum, mTOR activation is just a piece of the puzzle. Thus, the beloved leucine is a mere cog in the complex engine of variables that cause net gains in muscle.
Separating Macronutreints: Now carbs with fat/protein and no fat with protein/carbs and all that happy horseshit
J Beaty: What are your thoughts on the reemergence of the macronutrient food combining theory where carbs shouldn't be mixed with protein/fat meals and fat shouldn't be mixed with protein/carb meals?
L Norton: This is a rather simplistic way of looking at nutrition and focuses mainly on insulin rather than looking at the whole picture. While it probably isn't
a good idea to have a really high carb meal with a really high fat meal, there's nothing wrong with having moderate amounts of both.
W Brink: Like many theories, it comes around every few years or decades and gets people all worked up over their food. Problem is, it's no more true today than it was when the book “Fit for Life” by Harvey and Marilyn Diamond came out. The theory had no scientific support then and it has none now. Humans have been combining fats, carbs, and proteins quite successfully for eons, and as omnivores, are perfectly capable of digesting mixed meals.
J Hale: You are probably referring to the theory that assumes insulin and blood levels of fat should never be raised at the same time. This theory assumes that insulin is the key contributor to obesity. There are a few things wrong with this line of thought. One of the key problems is not recognizing something called Acylation Stimulating Protein. Acylation stimulating protein (ASP) is a hormone produced by adipocytes and is of importance for the storage of energy as fat. The consumption of dietary fat alone can increase fat storage. Dietary fat affects fat cell metabolism with NO INCREASE in insulin. Some studies have indicated dietary fat loading found a decrease in HSL (hormone sensitive lipase) and an activation of fat storage despite no increase in insulin. The key reason was activation of acylation stimulating protein (ASP) which is activated by the presence of chylomicrons (basically packaged triglycerides that are found in the bloodstream after the meal). ASP increases glucose uptake into the fat cell, increases insulin release from the pancreas and has been described as 'the most potent stimulator of triglyceride storage' in the fat cells by numerous scientists. Another problem with this line of thought is some proteins cause substantial elevations in insulin. Minimal levels of insulin affect fat cell metabolism. Basal levels can decrease lipolysis by 50%. Another consideration is most bodybuilders are eating every 2-3 hrs so nutrients are still absorbing from previous meals; therefore previous meals interact with the blood levels of nutrients of the present meal.
A study conducted by Golay and colleagues compared a diet with equal macronutrient content and substrate percentages; that differed only in how the substrates were consumed (mixed diet vs. food combining). The results were no difference in weight loss. Here are the exact results reported by the researchers:
“Results: There was no significant difference in the amount of weight loss in response to dissociated (6.2 +/- 0.6 kg) or balanced (7.5 +/- 0.4 kg) diets. Furthermore, significant decreases in total body fat and waist-to-hip circumference ratio were seen in both groups, and the magnitude of the changes did not vary as a function of the diet composition. Fasting plasma glucose, insulin, total cholesterol and triacylglycerol concentrations decreased significantly and similarly in patients receiving both diets. Both systolic and diastolic blood pressure values decreased significantly in patients eating balanced diets. The results of this study show that both diets achieved similar weight loss. Total fat weight loss was higher in balanced diets, although differences did not reach statistical significance. Total lean body mass was identically spared in both groups. CONCLUSION: In summary, at identical energy intake and similar substrate composition, the dissociated (or 'food combining') diet did not bring any additional loss in weight and body fat”. Actually looks like a slight increase in fat loss with mixed diet (balanced diet).
We have tons of anecdotal evidence that denies the need for food combining. We have evolved on a mixed diet. With all of that said, food combining may be beneficial regarding calorie control. Once you eliminate an entire macronutrient from a meal, this can go a long way in decreasing total caloric intake. If this is what you need to do to control energy intake, feel free to do so.
A Aragon: I think that the “P+C & P+F = okay but avoid C+F” principle is idiotic when applied across the board without any contingencies or attention to individual situations. For example, is someone is low-carbing for whatever reason you choose (pathological carbophobia included), they might be done with their carb intake by early afternoon, and their meal construction for the rest of the day is gonna be primarily P+F by sheer default. In the latter scenario, I can see the principle being legit.
However, when issued blanketly, it’s usually based upon the wacky idea that you don’t want fat floating around systemically when your insulin levels are high, because this will magically shift your net adipose balance in the positive. That’s false for a number of reasons. First of all, the insulin response generated by CHO + fat generally depends upon the degree of the fat’s saturation. Unsaturated fats tend to either lower insulin response of the co-ingested carbs, or not affect insulin response at all. Co-ingested sat fat, on the other hand, tends to raise insulin response, and can do so in a synergistic fashion. But then the question becomes, so what? Others have mentioned the more direct role ASP has in TG synthesis, and indeed, insulin is more of a multi-tasking anabolic/anticatabolic agent in comparison to ASP, which seems to exist solely to pump up the adipocytes. And of course the kicker is that ASP can do its TG-synthesizing magic in the sheer absence of insulin.
And then there’s energy balance… In a negative energy balance, insulinogenesis is wonderful thing, as long as the training stimulus & nutrition is there to work in concert with it to preserve LBM. In the condition of a positive energy balance, trainees in general are gonna have a lot more carbs to throw around, so this makes the whole separation thing even more dicey. Which meals should be carb-free or fat-free in order to pull of this magic separation tactic, and why? The logical answers to this question simply don’t exist. If you were to actually adhere to the mechanics of separation, you’d actually be hard-pressed to maintain a stable insulin profile – which is ironic, since the control of insulin is what “separatists” are aiming for. Regardless of all the previous points, the fundamental short sight is that digestion/absorption of meals overlap each other when meal frequency is as high as it should be. Therefore, attempting strict separation of the macros = kidding yourself. Not to mention, most foods in nature are a combo of all the macros to begin with.
Coffee and Insulin?
J Beaty: Some "experts" claim coffee should be avoided because of the insulin response that ensues, in lieu of the recent studies that have come out on coffee and blood glucose what is your stance on this?
L Norton: While acute caffeine ingestion may impair glucose tolerance, studies suggest that long term caffeine ingestion actually lowers the risk of developing type II diabetes(1). In my opinion there is probably not enough information at this point to say definitively one way or the other, but I believe caffeine is fine in moderation, much like many other compounds, if you don't abuse it there is little to worry about.
W Brink: As far as I am concerned, there is no sunshine without coffee! Kidding aside, it's essential to separate an effect seen in the lab and the larger picture. Insulin is an essential hormone in the pathogenesis of various afflictions. It's also a hormone we can't live with out, and there is not a direct insulin spike = terrible things happen equation, no matter how hard people attempt to paint insulin as the mother of bad guy hormones. Do we see a correlation between coffee and obesity? No. In fact, a study I was just reading found decreased rates of type 2 diabetes in men who drank coffee. If coffee had a negative effect on whole body glucose metabolism, that is it elevated insulin for long periods of time, or decreased insulin sensitivity to a great degree, or what have you, we would not see this reduced risk of type 2 and coffee consumption. If anything, it appears to have positive effects on glucose metabolism. There are several studies that suggest coffee reduces the rates of metabolic syndrome, which is yet more proof that it's far too over simplistic to paint coffee as a negative due to one outcome, in this case affects on insulin. There have also been a bunch of other potential benefits to coffee drinking, so as usual, it's about balance and common sense. A few cups of coffee per day are fine, 10 cups a day, probably not such a good idea. It's also possible that coffee may be contraindicated for some populations, but perfectly fine for the majority of people.
J Hale: I am assuming you are referring to caffeinated coffee. Caffeine increases the release of catecholamines (adrenaline, nor-adrenaline, dopamine). Adrenaline hormones increase FFA mobilization from fat cells. Dopamine increases feelings of pleasure and well being. Increased FFA blood levels due to high concentrations of adrenaline hormones induce insulin resistance. The effect is generally short term. The severity varies among individuals. We have to ask ourselves is insulin resistance a bad thing? Not always, just depends.
Fat cell insulin resistance means insulin can’t inhibit fat breakdown or promote nutrient storage in fat cell. Muscle cell resistance means the muscle cell can’t uptake glucose, therefore it uses an alternative source of fuel: FFAs. The glucose is utilized by the brain and nervous system and other tissues that need it. During times of dieting and low carbs insulin resistance is not necessarily a bad thing. When eating excess calories it generally is a bad thing.
With that being said, athletes have used coffee for years as a performance enhancer. Endurance athletes often ingest coffee because of its benefits on fat metabolism. Some studies suggest coffee may actually reduce chance of developing type 2 diabetes. Coffee contains other substances which have also shown health benefits. I recommend coffee if your body can handle it. Some people get the shakes and just can’t seem to handle the CNS boost. There is also a big difference between drinking 2 cups of coffee and 10. Moderation is probably the key to enhancing performance and preventing any negative health consequences.
A Aragon: I’m a coffee lover, so I’ll defend it with all my might, research be damned!! But seriously, all you can do in this instance is take a hard look at the data. The anti-coffee camp says that coffee consumption contributes to insulin resistance. This is a classic case of focusing on acute effects while disregarding what really matters – the chronic effects, along with a few critical details. This is also a case of context-confusion. Most of the work leading to this conclusion is based on obese folks using isolated alkaloidal caffeine, not coffee. So, to begin with, that pretty much takes most athletes out of the picture, who use caffeine for ergogenic purposes. They use it to increase exercise capacity, which inherently improves insulin metabolism, so pretty much the issue ends right there.
But we’re unrepentant nerds here, so we can still look at the data. Caffeine acutely raises insulin response when applied to oral glucose tolerance tests. Okay, great… Cocoa raises insulin response when co-ingested with other foods, but long-term cocoa use also appears to improve insulin sensitivity. Rewind back to coffee. Coffee’s acute insulinogenic nature doesn’t have any negative impact when studies are carried out long-term. For example, several epidemiologic studies found that ingestion of caffeinated (and decaffeinated) coffee may actually reduce the risk of diabetes compared with those who never drank coffee. In addition, coffee was recently seen to have a beneficial effect on endothelial function, which implies cardiovascular benefit. For those not impressed by the uncontrolled nature of epidemiology and prospective studies, I challenge anyone to compile the controlled studies on caffeine and dish out the conclusion that moderate coffee consumption has negative effects on health markers.
In addition, there are non-caffeine compounds in coffee currently under investigation such as chlorogenic acid, trigonelline, quinides, antioxidants, and others that have the ability to enhance insulin sensitivity. Moral of the story: a) Athletes (and regular folks) can use caffeine and/or coffee to their distinct advantage for performance and body comp improvement; b) Regardless of population in question, coffee can actually improve insulin sensitivity over the long term, likely due to its various beneficial non-caffeine phytonutrients. Check out this recent review, it covers way more than I’d ever care to:
http://www.ajcn.org/cgi/content/full/84/4/682 Coffee, diabetes, and weight control -- Greenberg et al. 84 (4): 682 -- American Journal of Clinical Nutrition[/url]
J Beaty: What are the most ignorant dietary theories and philosophies out there that are still incorporated by the bodybuilding population?
L Norton: 1. Don't eat carbohydrates after 'X' o'clock. People believe that since they are closer to sleeping they should curtail carbohydrate intake, this is simply ludicrous. Carbohydrates at night don't make you fat; too many total calories make you fat. Additionally, if you train at night you NEED those carbohydrates to
Further from Layne's Q&A
Question: I sometimes work out pretty late at night (finish at around 9) and was wondering if my post workout meal strategy should change as a result. I'm cutting on a low carb diet, by the way. I usually have my post workout drink with about 90g of carbs, and an hour after that a meal with some carbs and protein, but since this would mean eating at 10 p.m. (I go to bed at 11), I'm afraid of fat gain while I sleep. I did my usual thing yesterday and could swear I felt some bloating. Any suggestions?
MY ANSWER: You are approaching the situation almost the exact same way I would do it. Make it a point to have very little to no carbs throughout the day and same most of them for your workout so you can recover properly. DO NOT SKIMP on post workout nutrition, even if you are cutting. If you don't get an adequate amount of carbohydrates into your system to refill your glycogen stores your recovery will surely be hampered. You should also have some complex carbs right before bed since the simple carbs that you ingest with your post workout shake will not last you very long and these complex carbs will help spare muscle protein while you sleep. You should also have a slow digesting protein source immediately before bed.
Don't worry, if you're in calorie deficit and your workouts are intense your body will not be "worried" about synthesizing fat, it's first priority will be to refill your depleted glycogen stores and repair your atrophied muscle tissue, these carbs will most likely not be stored as fat. The bloating you experienced is most likely from water retention from the carbohydrate in gestation. For every gram of glycogen your cells store they also bring in 2.7g of water, so you can see how you might feel bloated, it is nothing more than water retention. My guess is when you wake up you look rather crisp, as the water retention is likely to have subsided by that time.
2. The notion that high rep ranges stimulate slow twitch fibers & low reps stimulate fast twitch fibers. The fact of the matter is that while high reps do
stimulate slow twitch fibers, SO DO LOW REPS with heavy weights. You see your fiber types are recruited in order of need: slow twitch first, then intermediate, then fast. So as you can see, if you are lifting heavy loads for low reps you have already
maximally stimulated your slow twitch fibers.
3. The notion that a specific rep ranges yields the best results. Some people believe you should only lift high reps because the pump is so important while others believe that you should only do low reps with heavy weights because training this way maximally activates all fiber types. The reality is ALL rep ranges have benefits and they should ALL be utilized to achieve optimal results.
W Brink: I actually think things in this area have improved greatly. The advent of the Internet has probably helped a great deal there. It seems that almost everyone at this point understands and appreciates the basics, which is you need adequate protein, fat, and carbs to gain lean body mass. For example, the ultra high carb, low fat diets popular back in the day have all but disappeared. Most people know they need some fat in their diet, know they need some EFAs, and know the basics between low GI and high GI carbs, and so on. That's not to say there is not confusion and questions about all of the above, but as a general rule, I think most people have at least a basic understanding better then they did say 10 years ago. The area of real ignorance that seems to persist no matter how hard people like me attempt to counter it is in the area of supplementation. Supplements seem an endless source of confusion and scams.
J Hale: A couple that come to mind immediately are the assumption that bodybuilders trying to get lean should not eat fruit and bodybuilders’ over-reliance on supplements. The fear of fruit comes from studies suggesting 50 gms or more of fructose per day can upregulate de novo lipogenesis (fat synthesis in liver), increase blood triglycerides, and induce insulin resistance. Keep in mind fruit generally contains 6-7 gms of fructose. That means it would take a bunch of fruit to get 50 gms of fructose. The high consumption of fructose seen in most studies is generally due to the consumption of high levels of high fructose corn syrup (processing where varying portions of glucose are converted to fructose). Another consideration is fructose causes minimal insulin secretion. Even if fructose consumption was high enough to elevate fat synthesis lack of insulin would probably result in increased fat oxidation. Assuming calorie deficit it probably all evens itself out at the end of the day. Eat fruit - it's nutritious and generally low in calories.
Bodybuilders have forgotten the meaning of supplementation. It means supplement the training and nutrition regimen. Be sure your training and nutrition are efficient before spending hundreds of dollars on supplements. Some supplements are beneficial and more convenient than fixing food all the time. They (very few) have a role in physique and performance enhancement when used in the appropriate manner.
A Aragon: The bodybuilding population as a whole is carbophobic. And I’m talking about carbs in all forms. Don’t get me wrong, in the event that calories must be reduced, or reduced to a heightened degree such as pre-contest, its plain stupid to incur a protein deficiency. But in general, bodybuilders are just plain afraid of carbs. Hell, only a small percentage of bodybuilders are up on the science of the matter, so the rest are victims of the asinine mass media just like every other layperson. Would it alarm you to know that the majority of “serious” recreational and competitive bodybuilders are literally afraid to have carbs in their final meal? Imagine that, they’re mortally afraid of muscle loss while simultaneously being afraid of a key tactic that can enhance lean mass preservation. True story.
On those same lines, you have the carbophobes who have a mortal fear of insulin, yet megadose highly insulinogenic BCAA during training. Oh, no glucose generated there, none at all, hah… What a lot of folks don’t realize is that BCAA is approximately twice as insulinogenic as a solution of pure glucose.
On those same lines, you have folks who are stuck on acute substrate utilization during training. I was talking to a friend of mine Alwyn Cosgrove the other day (Braveheart is still a cool movie even though Mel lost it), and the following realization dawned on me as a matter of what we discussed:
Caring about how much fat is burned during cardio makes as much sense as caring about how much muscle is built during weight training.
I recently had a rather public debate, and by all counts absolutely destroyed my opponent’s argument that fasted cardio was across the board better for fat loss than fed cardio. He was focused on acute effect (during & shortly after exercise), not long-term effect, or anything close to the research blatantly refuting his stance. More reading on the subject of “fat burning” cardio can be found here:
Articles - AlanAragon.com
This brings me to another rant… Folks with any intention to use being published in peer-reviewed journals as some sort of credibility crutch have another thing coming. People of sound mind don’t give half a rat’s ass where someone’s been published. We don’t care what degrees you have, we don’t care how many hours you’ve spent in a classroom listening to the drone of professors who have never driven near the gym. I can tell within 5 sentences whether someone is worth listening to or not. Paper credentials are fine and dandy, but they mean nothing compared to the ability to reason, comprehend, and synthesize ideas and information. In the realm of bodybuilding, academic degrees also must take yield to experience using these abilities firsthand either on yourself and/or in working with clients – that’s the most relevant “lab”, as far as I’m concerned.
This brings me to the duality of scientific research. We as “thinking” bodybuilders rely on research to mold our beliefs, support our stance on controversial issues, and ultimately, dictate our protocols. Science indeed is infinitely more reliable than random opinions of buff dudes with hyooge byceptz & rippt abz. But unfortunately, even science is puppeteered by money and politics. For example, whoever pays for the study is gonna get the results they want. That’s brutal but true. The best we can do in any given debate is see whether controlled research over time is able to produce counter-results from the opposition (which hasn’t yet occurred in the case of the anti-milk camp, HAH!), or whether relatively non-vested replication and further validation ensues. It goes without saying that all research must be scrutinized for strengths and weaknesses.
Which brings me to another rant… I can’t stand it when anyone picks a stance and makes a bulletproof commitment to it, turning a blind eye to any opposing data, regardless of its legitimacy. A lot of guys in this industry seriously handicap themselves by assuming a singular position that they feel defines them. This is something we’re all guilty of from time to time, and it definitely impedes the growth of wisdom.
There’s more, perhaps we could cover them in another segment.
J Beaty: Who are the brightest minds in the world of nutrition?
L Norton: I'm biased since he is my graduate adviser, but Dr. Donald Layman really has a tight grasp of most facets of nutrition. He understands the biochemical details but never loses sight of the big picture and always is asking the question "how does this (insert topic) relate to the real world & how can we apply it effectively?" Dr. Peter Garlick's work on protein metabolism is outstanding as is Dr. Leonard Jefferson's. I comment on these individuals as they are some of the best in the field of protein synthesis/metabolism which is the field I specialize in. I'm sure there are many other great minds that I have left out, but I don't feel qualified to comment on experts in other areas of nutrition.
W Brink: Too many to list. Also, no matter how many people I list, someone will be left out and take it personally.
J Hale: I like numerous people in the field including Lyle McDonald, my fellow panelists for this roundtable, MJ Rennie, Kevin Tipton, and Dan Moore to name a few.
A Aragon: As far as authors go, my earliest influences were Michael Colgan and Dan Duchaine. I don’t know anyone in his right mind who lived during Dan’s rise in print media who wouldn’t name him on their list either at or near the very top. More recently, Lyle McDonald has impressed me in terms of both his books and his ongoing science and logic-based contributions to the fitness community at large. That’s the thing. A lot of guys attempt to be scientific, but they miss the boat on being logically consistent. That list isn’t very voluminous, but I’m open to suggestions. I just happen to spend way too much time on Medline, and I’m sure much of the current crop of worthwhile book authors has escaped my radar.
As far as research scientists go, it would give me a headache to rattle off even a fraction of the ones whose work I’ve admired & benefited from. Peter Lemon, Kevin Tipton, David Costill, Mark Tarnopolsky, Susan Holt, Robert Demling, Xavier Pi-Sunyer, Robert Wolfe, William Kraemer, Edward Melanson, and Mark Febbraio really stand out. I’m sure that on any given moment I can think of others I missed who’ve really made an impact on my personal methods and perspectives.
Bobo of anabolicminds.com isn’t a book author or researcher in the formal sense, but he’s a bodybuilder who influenced how I view the current dogma. Almost any intelligent person who you have a lengthy heated debate with inevitably imparts some sort of wisdom upon you, and Bobo stands out in that arena.
Oh yeah Jamie, go ahead and add yourself to the list . Readers, let me tell you that Jamie is one of the most obsessively voracious students of this game that I’ve ever met. The guy’s idea of a good time is exchanging & discussing full text articles via email.
I’m sure there are others I missed.
J Beaty: Generally speaking, what body fat percentage do you allow your bodybuilders to reach before beginning a lean out phase?
L Norton: It all depends upon their body fat set point. If a person is heavier by nature, then they probably need to carry a tad more body fat in order to put on muscle mass, whereas an ectomorph can probably stay at a lower body fat & put on muscle mass. Typically I aim for a percentage range. If a person is typically around 15% I try to keep them within 13-16%, while if a person is typically 6%, I'll try to keep them within a range of 5-8%. If they fall below the range, I suggest increasing calories; if they start to go above that I temporarily restrict calories. As a rule however, no one should ever allow themselves over 20% body fat. The more body fat one puts on, the more they will desensitize themselves to insulin, making it harder to build lean tissue. Additionally, at higher body fat levels, the body may not merely just increase fat cell size, it may start making new fat cells and once your body makes new fat cells, they are yours to keep - you can't get rid of them. The long term effect of this would be an elevation of a person's body fat set point.
W Brink: For men, approx 12-14% is as high as I would let a man go. For women, around 16-18%. Both are not written in stone, however. People carry their weight differently. I recall Lee Haney saying his rule of thumb was as long as he could see a hint of his abs, he was OK for an off-season fat percent, but if he could not see his abs, it was time to drop some fat. I do think for people to really optimize increases in LBM and or strength, it’s counterproductive to attempt to stay in single digit body fat levels year round.
J Hale: Hard to place a specific number on that value as athletes widely vary. I have seen athletes get up to 18% and have no problem getting lean when it was time. I have seen others who really seem to have problems if they get over 12-13% body fat. In the past I recommended that bodybuilders didn’t get over 13%. Based on my experience, I now play that by ear as it completely depends on the individual.
A Aragon: This question carries the implication that all bodybuilders must undergo separate phases. This really only applies to my clients in formal competition, where specific phases are unavoidable. For non-competitors, and even competitors to a modified degree, I prefer the “culking” approach. This is a tongue-in-cheek term I coined which basically fuses the whole cutting & bulking cycle in to one slow, steady, refinement of the physique in terms of both size AND leanness. This is entirely possible to achieve, but the timeline is generally a period of years rather than months. In the purest sense, culking is a perpetual process that’s linear for the most part. The typical cycle scenario is spending half the year looking like a bloated mess, and the other half looking decent to drawn. At fleeting points for only a few weeks (or days) at a time, they look great. That doesn’t sit too well with me.
Back to the question, which I’ll apply strictly to competitors. I’ll speak from the perspective of calipers since that’s my preferred instrument. Given that, I’m a huge proponent of the slow approach to competition prep. I don’t like to see much more than 1% BF drop per month, and even less than that is warranted (closer to 0.5% a month) as mid-single digits approach. It stands to reason that for a 3-6 month dieting phase (depends on the individual), I don’t recommend that guys go more than approx. 3-4% above their competition level, which again varies with the individual. With calipers, some guys look good enough to hit the stage in the 3’s; younger folks with tighter/less collapsible skin often look good enough in the 4-5’s. Keep in mind that ultimately, the mirror beats the calipers.
J Beaty: In terms of nutrition, what are the biggest psychological barriers you feel bodybuilders face?
L Norton: Trying to get results too fast, either trying to lean out to quickly or trying to add muscle mass too quickly. When a person tries to lose body fat too fast, they end up sacrificing muscle mass, but when a person tries to add muscle mass too fast they end up putting on way too much fat mass. The name of the game is patience. Bodybuilding is not a sprint, it is a marathon.
W Brink: Nutrition is such an emotionally loaded topic people often make decisions on what they eat based on psychological considerations, like what their mom forced them to eat, or what their religion tells them they should eat, etc. Classic barriers I see are people that can't accept one needs to eat some fat to lose fat and be healthy, or that they need to eat additional calories if they want to add muscle, and the fact that some body fat increases will occur. Bodybuilders are no different then regular people in that respect. In fact, they are often more neurotic then the general population which can be both an advantage and a detriment to their progress depending on how that neurosis manifests itself. It's been my experience that half the time you are deprogramming people to get them past all the hang ups, neuroses, and misinformation they carry around.
J Hale: For competitive bodybuilders, one of their biggest obstacles to overcome is their fear of becoming too small. When pre-contesting dieting happens, some bodybuilders see significant decreases in bodyweight and measurements (depending of body comp pre pre-contest diet). This actually affects many in a negative way especially when people starts asking ‘what’s happening, are you sick?’ In fact, I have had numerous athletes start a pre-contest diet and stop the diet about half way through because they can’t handle the drastic drop in weight and measurements. Some trainees could actually do great in competitive bodybuilding if it wasn’t for the fear of becoming too small. Another common psychological barrier for bodybuilders is the assumption they need to look like a pro to compete. There is a big difference between amateur and pro bodybuilding.
A Aragon: Bodybuilders in general are psychologically traumatized individuals. But this is true with most great athletes regardless of sport. On a subconscious level, they’re trying to overcompensate in order to rectify some sort of trauma or perceived inadequacy. So, they face the primary demon of giving a damn about what everybody else thinks, and trying to compete with everyone but themselves. They let their environment dictate their standards, when they should be setting and competing with their own standards. Improving yourself from one day, week, month, or year to the next is really what it’s all about.
J Beaty: What are the biggest mistakes you've seen bodybuilders face both in pre-comp and mass building phases?
L Norton: Pre-comp mistakes are numerous but include: massive carb ups, massive water depletion, massive sodium depletion coinciding with potassium loading. Probably the biggest mistake is UNDERESTIMATING how much weight one will have to lose to be in contest condition. Mass building mistakes: Trying to put on mass too fast and end up putting on body fat would be the most common one. Another mistake is trying drastic diets such diets super high in any macronutrient or super low in another. Moderation is the name of the game... there are no shortcuts to a great physique.
W Brink: Pre contest, Attempting too many last minute tweaks in hopes it will help them peak only to have it blow up in their face. Most body builders think if they don't look and feel terrible the last few weeks up to a show, they are doing something wrong. Carb depletes and loading, sodium loading, and all manner of last minute alterations that more often then not, leave the person looking worse not better. It either backfires in their face and does not work at all or they miss their peak and look great a few days after the show. I recall talking to Dorian Yates who maintained he didn't bother with any of those extreme last minute changes and just stayed a steady predictable course pre-contest. If you look great a few weeks out, then just keep doing what you are doing. I do tell people a small carb load a 3-4 days out is often a good idea as a proper pre-contest diet is mildly glycogen depleting anyway, and so topping off the tanks seems to help fill people out without water retention - but no drastic loading or depleting is needed if you have done your homework the months before. 9 out of 10 times. Off season, seems one of two extremes: bodybuilders who want to stay lean and eat nothing but rice and chicken, then can’t figure out why they don't grow, and bodybuilders who use the off season to get sloppy fat and eat what ever they want.
J Hale: It is really hard for me to give an answer that does not require an entire article. To keep it brief: doing way too much activity while dieting and losing bodily proteins. In the off season, developing horrible eating habits that are hard to overcome; once it’s time to start the pre-contest diet.
A Aragon: Pre-contest mistakes basically fall into 2 categories that beget each other: 1) Underestimating prep time; 2) Pulling drastic last-minute moves to try to fix mistake number one.
I’ve found that many guys actually do their first show as a motivator to get out of Fatville. That’s fine and dandy, but if you’re a guy clocking in at 20% BF, and you think you won’t be stressed out about your lower abdominal pudge in 12 weeks, then go for it. We’ve all seen dudes get onstage chubby by contest standards, but just having a blast and enjoying their current peak shape.
Guys often think of the first set of Body For Life 12 week before & after shots and don’t realize that the guys who got shredded for that were more than likely what I call “rebound rippers”. They’ve been in great shape before, so their body had the pre-existing infrastructure and “memory”. For them it was simply a matter of bouncing back after a period of extreme slack. If you’ve never been there, it’s quite the road to get there.
The drastic last-minute moves I’m talking about mainly deal with desperate random water and sodium moves, as well as exponential hikes in exercise coupled with precipitous drops in caloric intake. Not to mention doubling & tripling the reps, thereby forcing useless endurance adaptations at the expense of preserving size.
As far as off-season mistakes go, that’s pretty easy, getting too fat. Also, guys need to take more extended rest periods. 1 full week (even up to 2) of zero formal training approx. every 3-4 months. These objectives may seem contradictory, but they’re actually not when executed properly. Regular extended rest can actually accelerate progress more than the absence of it.
J Beaty: How do you manipulate water consumption pre-comp?
L Norton: I don't. It should stay high the whole time. Unless a person is on androgens that cause massive extracellular water retention there is NO NEED to cut water! Natural competitors just DO NOT hold that much extracellular water. If you cut water, not only does your body fight you by releasing hormones that cause you to retain more water, you also flatten yourself out and make any carb loading you do ineffective. Muscle tissue is 70% water, and cutting it out will deplete subcutaneous water, but it will also deplete water from inside the muscle cell causing the competitor to look flat, stringy, with no vascularity. At my last show where I won my NGA pro card, people were looking at me like I was crazy while I was downing water backstage. They asked "aren't you worried about retaining water?" I just smiled & said "not a bit." Then they couldn't believe how full & dry I was when I took my clothes off & started pumping up. The competitors I prepare for shows also typically have the same comments, they can't believe how dry they stay while drinking so much water and they can't believe how much more vascular they are.
W Brink: To be honest with you, I don't work with pre-contest bodybuilders much any more. The use of lasix and other diuretics was not something I was comfortable with, and decided the smart thing to do was to step away from that line of work. Non-pharmacologically speaking, as far as simple water consumption, limiting water a few days before often helps dry people up, but I am not a fan of seeing people go to essentially zero water intake for days before a show. It's damn unhealthy and does not seem to yield the results people want. Now, people who really know how to manipulate water via diuretics and other drugs and tricks can do some amazing things. I recall seeing one very well known pro about 3 weeks out from a big show. He looked terrible and I thought there was no way in hell he would peak for the show. He employed a well-known pre contest guru known for being particularly adept at the use of diuretics, and the transformation was amazing. He won the show.
J Hale: Three days from the show I advise bodybuilders to increase water intake above previous levels. Two days from the show the water depletion process begins. Example: they drank 2 gallons of water the previous day, two days before the show they drink 1 gallon. One day from show water consumption drops further to approximately ½ gallon (distilled water). The day of the show I recommend consuming 12-16oz distilled water up to the pre-judging. After pre-judging sipping water as needed. At the same time I am manipulating sodium, Vit C, Carbs, and potassium in the quest to achieve that dry as a bone appearance. Being dry is very important for competitive bodybuilders.
A Aragon: I hold very strongly to the philosophy that the best possible manipulation of water is to not need to manipulate water at all. Fact is, it’s easy to actually be 4 weeks out at the 4 day mark, but blame it on water, when it’s actually good ole subcutaneous fat. That’s the first principle: dial in your BF at least 2 weeks in advance. That’s how Dorian did it (among other means of course), but he would go shopping on the day of the Olympia while other guys stayed in their hotel rooms and prayed in desperation.
That said, if last minute tweaks need to be done, the effects vary drastically from one individual to the next, so it’s important to do a dry run far out from a show if you plan on tweaking. Kevin Levrone made it popular to overdo water intake beginning a couple days out from the show, all the way through to the stage. Well, actually he’d get an alcohol buzz right before going on. He figured that if he was coming in bigger and harder than the water-starved competition, why monkey with the strategy. But it does make sense (the increased water, not necessarily the buzz) from a physiological standpoint, and I’ve been heavily influenced by that approach, and have used it with reasonable success with clients when the need arose.
Then you have other guys who swear by the cut-it-low 2-3 days out method, which actually activates your body’s water-retentive defenses, and puts most natural guys at a greater risk for coming in skinny AND softer than they would have been. I think it’s ludicrous to believe that you can manipulate exactly whether water will escape the subcutaneous layer versus the intramuscular space. People confuse the aforementioned respective terms with extracellular & intracellular space. If you can keep water & sodium relatively constant throughout prep, that’s ideal. In my experience, water and sodium increases/decreases should generally be in tandem with each other, and not too different from habitual amounts. Gotta see how the individual responds, bottom line.
J Beaty: Describe the perfect bodybuilder...in one word.
L Norton: Impossible, lol
W Brink: Flex Wheeler. I guess that's two words.
J Hale: An individual with good bodybuilding genetics (naturally muscular, basically mesomorporhic bodytype, small joints, nice shoulder to waist ratio-tapered look, high p-ratio) great discipline, incorporates scientific findings into his training, thinks with and open mind, and can handle criticism.
A Aragon: Sane.
Bios & Contact info:
Layne Norton, IFPA & NGA Pro
1. Battram DS, Arthur R, Weekes A, Graham TE. J Nutr. 2006 May;136(5):1276-80. The glucose intolerance induced by caffeinated coffee ingestion is less pronounced than that due to alkaloid caffeine in men.
Last edited by EricT; 04-17-2007 at 10:46 AM..
|01-26-2007, 09:29 AM||#2|
| hrdgain81 |
Rank: Light Heavyweight
Experience: 5-7 Years
Join Date: Mar 2005
Eric, that was a great post. Alot of useful stuff in there. I perticularly like the discussion on the mTOR path way. I've seen decent growth, and apetite supression while superdosing BCAA. it makes sense why that would happen now.
This really suprised me:
The Caffiene discussion also interested me quite a bit. Its not always easy to understand when isulin resistance is a good thing, but it seems a little more clear to me now.
A Aragon is a funny guy, I like his writing style here.
|01-26-2007, 11:54 AM||#3|
| ChinPieceDave667 |
Experience: 5-7 Years
Join Date: Apr 2005
Location: 7th layer.. or DC.
A very useful read. I definitely learned more about nutrition, especially from these ones.
I liked the coffee one too just because I need my coffee.
And, the section about fruit was very interesting, didn't know that the studies were also talking about fructose corn syrup.
|01-26-2007, 12:34 PM||#4|
| EricT |
Experience: 7-10 Years
Join Date: Jul 2005
I kinda adlibbed some of those comments in yellow to make it easier to read
I like these roundtables a lot because it's really useful to get these different viewpoints from guys who are really students of this stuff and at least try not to slant their viewpoints based simply on "pretty science".
Hrdgain, I like Aragon too. I posted his "Myths Under the Microscope" articles here and there is a link to them along with another atricle about the glycemic index I am going to read. The myths articles are well worth reading, IMO.
Dave, I never believed much in the fruit thing to tell the truth but that gave me some more concrete info to go on. You know on the whole glycemic index thing one thing I had mentioned also in the Glycemic Index sticky is the difference between glycemic impact and glycemic load.
It is important for people to realize that glycemic impact is measured by using 50 grams of carbohydrates with a given food. No matter how much of that food it takes. So you'll see carrots have a "high" glycemic index but what is not realized is that it takes about TWO POUNDS of carrots to make 50 grams of carbs, lol. That was the example that sticks in my mind. The glycemic LOAD of ONE carrot or TWO is minuscule to the point of absurdity in comparison. Thats off subject as far as corn syrup vs. fruit, I know but it just put me in mind of it.
On coffee I actually had a doctor tell me he thought there was no way I would ever get off it, after he found out I've been drinking it since I was four!
|01-26-2007, 01:02 PM||#6|
| EricT |
Experience: 7-10 Years
Join Date: Jul 2005
Honestly that's not the message I get. I think many bodybuilders actually make it more complicated than it is. If your really read closely and consider what these guys are saying, not just in this article but in other similar works, you'll see that this overzealus attention to detail rather than the big picture is more of a downfall than a help.
I'm speaking more of the average person not looking to step on stage. I think it's a big mistake when people apply what is appropriate to a proffessional gentically "elite" bodybuilder, and the machinations they go through for the sport and apply that to your needs. Most of what these guys saying actually tend toward simplifying things becasue of the application of good old common sense. You can't put together a puzzle by focusing all your attention on one or two pieces.
|01-26-2007, 01:10 PM||#7|
| ChinPieceDave667 |
Experience: 5-7 Years
Join Date: Apr 2005
Location: 7th layer.. or DC.
|01-26-2007, 01:17 PM||#8|
| EricT |
Experience: 7-10 Years
Join Date: Jul 2005
|01-26-2007, 01:27 PM||#9|
| EricT |
Experience: 7-10 Years
Join Date: Jul 2005
Dave I'm going to go ahead and post Aragon's article on the GI here as well.
Elements Challenging the Validity of the Glycemic Index
By Alan Aragon © 2006
Another Magic Bullet is Bound to Ricochet
To this day, many bodybuilding, health, & fitness enthusiasts stake their entire moral judgment of carbohydrate foods based on their glycemic index (GI). A considerable set of confounders challenges its validity & strict application. Becoming blindly enamored with something that may enhance our physiques &/or health is natural, and something we've all been guilty of. But alas, the GI data is neither perfect nor consistent, nor is it free of bugs. Consider the following facts, and re-think the dogma surrounding GI, & reassess what you think you know about GI.
A Possible Definition Shift
The simplistic definition of GI is a food's ability to raise blood sugar, which almost automatically is regarded in terms of glucose entry into the blood. However, recent eye-opening research by Schenk & colleagues clearly showed that the rate of disappearance of glucose from systemic circulation is an important determinant of GI - not just glucose's rate of entry into circulation . They found that the lower GI of bran cereal was due to a quicker/sooner surge of insulin sweeping glucose out of circulation - not a slower appearance/entrance of glucose as once assumed. Although strictly speculative at this point, this phenomenon may have possible performance detriment implications (ie, rebound hypoglycemia) in sensitive individuals if meals of this nature are mistimed relative to training.
Determination Vs. Applicability
GI values are determined in an overnight-fasted state using isolated foods. This is not a reflection of real life, where the digestion/absorption of previous meals, as well as the context of the carbohydrate food can drastically alter GI.
The interplay of many variables can either raise or lower GI, and are often difficult to control. Increased acidity, the presence of fiber, fat, and certain protein foods can lower glycemic response. Reduced particle size, greater ripeness, and heat in cooking can raise glycemic response.
Glycemic Load Disparity
Glycemic load (GL), which is the amount of carbohydrate per serving or unit of volume, is not always directly proportional to GI. For example, watermelon has a GI of 72, which is considered high. Low-GI advocates have vilified watermelon without realizing the fact that it has a relatively low glycemic load, approximately 6g carbohydrate per 4oz serving. The same disparity of GI & GL applies to carrots, potatoes, and even sports drinks such as Gatorade.
Satiety Index Disparity
Lower-GI foods have been associated with greater satiety, but most of this data comes from single-meal experimental designs. Longer-term studies on GI & satiety are conflicting, and not always controlled for energy intake and energy density of the test meal . In the longest study to date on GI & satiety is an ad libitium 30d crossover design where Kiens & Richter observe no difference in amount of consumption . In this metabolic study, a LOWER resistance to insulin was seen in the high-GI group at the end of the trial. GI does not reliably correspond with satiety index (SI). White rice, wheat bread, and potatoes all have high GIs, but rank among the top of the list for delaying the onset of hunger. In fact, Holt's team found that potatoes had by far the highest SI of all the foods tested .
As a classic example of chaos physics, the typical rules that predict GI do not necessarily help in predicting insulin response. Unfortunately for GI-conscious people, insulin is usually what they are trying to control. Despite having a very low GI of 15-36, milk and yogurt have a high insulin index equivalent to that of the high-GI white bread . Baked beans, another low-GI food, have a very high insulin index of 120. Cheese, beef, and fish have II's that are comparable to many carbohydrate foods.
Coingestion of fat with carbohydrate slows gastric emptying and thus the release of glucose into the blood, ultimately lowering GI. While this is usually true for GI, the degree of insulin response evoked by this combination is determined by the degree of the fat's saturation. For example, Collier & others observed that butter coingested with potato not only fails to lower postprandial insulinemia, it actually causes a synergistically heightened insulin response, even in healthy subjects [6,7].
Foods that should have a low GI due to their high fat content do not always have a low GI. Examples are fries, cookies, croissants, and doughnuts. Incidentally, these foods also have a high insulin index, presumably because their fat is mostly saturated. As of this writing, full-fat ice cream (low GI of appx 37) has not been tested for II, but it's safe to assume that it probably has disparate GI & II values.
Rasmussen & colleagues observed no increased insulin response with the addition of 40g or 80g olive oil, but saw a significant increase with 50g & 100g butter . Joannic's team observed a coingestion of carbohydrate with fats of increasing degree of unsaturation having a corresponding decrease in insulin response . A more recent study by Robertson & colleagues compared the effect of MUFA, PUFA, & SFA coingestion with carbohydrate and observed SFA's superior ability to raise postprandial insulin levels .
Coingestion of protein with carbohydrate is often recommended to lower GI. However, this doesn't necessarily lower insulin response. Carbs combined with protein in solution can pretty reliably raise insulin response synergistically. Gannon & Nutall's research on type-2 diabetics showed that coingested cottage cheese & glucose raised insulin levels beyond either food separately, indicating a synergistic effect . Van Loon & colleagues saw a similar phenomenon when comparing the insulin effect of various carb-protein/amino acid and carb-only solutions in normal subjects . Those containing free leucine, phenylalanine, & arginine, and the drinks with free leucine, phenylalanine, & wheat protein hydrolysate were followed by the largest insulin response (101% and 103% greater, respectively, than with the carb-only solution). These are only a few examples of many.
GI & Obesity - Slim Chance For Correlation
A systematic review of human intervention studies comparing the effects of high and low-GI foods or diets arrived at the following results :
• In a total of 31 short-term studies, low-GI foods were associated with greater satiety or reduced hunger in 15 studies, whereas reduced satiety or no differences were seen in 16 other studies.
• Low-GI foods reduced ad libitum food intake in 7 studies, but not in 8 other studies. In 20 longer-term studies (<6 months), weight loss on a low-GI diet was seen in 4 and on a high-GI diet in 2, with no difference recorded in 14 studies.
• An exhaustive assessment of these human intervention trials found no significant difference in the average weight loss between low & high GI diets. in conclusion, the current body of research evidence does not indicate that low-GI foods are superior to high-GI foods in regard to treating obesity.
More recently, Raatz & colleagues conducted a parallel-design, randomized 12-week controlled feeding trial, testing the effect of GI and GL on weight loss . The controlled period was followed by a 24-week "free living" phase, in which subjects were instructed to continue their respective dietary treatments outside of lab-supervised conditions. Manipulation of GI & GL failed to make a dent in both experimental phases. As a result of the 36-week trial, the researchers conclude: "In summary, lowering the glycemic load and glycemic index of weight reduction diets does not provide any added benefit to energy restriction in promoting weight loss in obese subjects."
Conclusions (For Now)
GI is gives us clues to the behavior of certain foods, but that's exactly the main point of this article. Clues; mere hints are all we get from our current knowledge of GI. Successful application of GI is most consistent when we use higher GI sources to enhance the speed of postworkout glycogenesis, and that's about it. Carb foods are better judged on the basis of degree processing, refinement, or alteration/removal of micronutrition -- NOT on the basis of GI, or even GL. This is as good a time as any to crush the folly of what I call "food discrimination". A prime example of this is cutting out potatoes on the basis of GI. This happens all the time, & the dieter takes pride in thinking he/she is being prudent. Well, the critical thing to realize here is that all food species in nature have unique nutrient profiles. Therefore, unique nutritional benefit can be derived from each species. The natural matrix of plant &/or animal tissue cannot be duplicated in the lab, & hence there are many unidentified beneficial agents in, say, the humble potato. As a matter of trivia, it surpasses bananas in potassium & vitamin C concentration. Not to mention, it provides default hydration, and of course is a great whole-food source of starch. The list goes on & on.
Satiety, micronutrient density, insulin response, & surrounding factors altering glucose kinetics are all much like a roll of the dice in terms of bottom-line certainty & reliability of GI. Like all things in science - especially the deep bubbly cauldron that is applied nutritional science - it ain't all that simple. All avenues in this area are winding & complex.
Schenk S, et al. Different glycemic indexes of breakfast cereals are not due to glucose entry into blood but to glucose removal by tissue. Am J Clin Nutr 2003;78(4):742-8.
Pi-Sunyer FX. Glycemic index and disease. Am J Clin Nutr 2002 Jul;76(1):290S-8S.
Kiens B, Richter EA. Types of carbohydrate in an ordinary diet affect insulin action and muscle substrates in humans. Am J Clin Nutr 1996;63:47-53.
Holt SH, Miller JC. A satiety index of common foods. Eur J Clin Nutr 1995 Sep;49(9):675-90.
Ostman EM, et al. Inconsistency between glycemic and insulinemic responses to regular and fermented milk products. Am J Clin Nutr 2001; 74(1):96-100.
Collier G, et al. The effect of coingestion of fat on the glucose, insulin, and gastric inhibitory polypeptide responses to carbohydrate and protein. Am J Clin Nutr 1983;37(6):941-4.
Collier G, et al. The acute effect of fat on insulin secretion. J Clin Endocrinol Metab 1988;66(2):323-6.
Rasmussen O, et al. Differential effects of saturated and monounsaturated fat on blood glucose and insulin responses in subjects with non-insulin-dependent diabetes mellitus. Am J Clin Nutr 1996 Feb;63(2):249-53.
Joannic JL, et al. How the degree of unsaturation of dietary fatty acids influences the glucose and insulin responses to different carbohydrates in mixed meals. Am J Clin Nutr 1997 May;65(5):1427-33.
Robertson MD, et al. Acute effects of meal fatty acid composition on insulin sensitivity in healthy post-menopausal women. Br J Nutr 2002;88(6):635-40.
Gannon MC, et al. Metabolic response to cottage cheese or egg white protein, with or without glucose, in type II diabetic subjects. Metabolism 1992;41(10):1137-45.
van Loon LJ, et al. Plasma insulin responses after ingestion of different amino acid or protein mixtures with carbohydrate. Am J Clin Nutr 2000;72(1):96-105.
Raben A. Should obese patients be counselled to follow a low-glycaemic index diet? No. Obes Rev. 2002 Nov;3(4):245-56.
Raatz SK, et al. Reduced glycemic index and glycemic load diets do not increase the effects of energy restriction on weight loss and insulin sensitivity in obese men and women. J Nutr. 2005 Oct;135(10):2387-91.
|01-26-2007, 03:20 PM||#10|
| Kane |
Experience: 3-5 Years
Join Date: Nov 2005
My initial reaction to the article was that it was simplifying things and de-throning certain "myths", but at the same time they're throwing around alot of jargon and technical terms. Overall it is a very helpful read and will hopefully shut up alot of those weekend warriors at the gym that believe coffee is the devil...lets face it, coffee and beer go hand in hand
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