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Evan Levy
03-23-2009, 02:03 PM
I am currently working at a facility that is all about high carb/high glycemic load diets to improve performance and health. I have been trying to find specific studies/journal articles that prove a low insulin and proper balance of macronutrient meal plan can improve performance and reduce the risk of disease. I have been zoning for 5 months and have seen benefits first hand, however, I want more studies to prove that there is an alternate route to a high carb/insulin diet. Any and all information would be helpful.

Mike ODonnell
03-23-2009, 04:27 PM
Is this a "sports performance" place by any chance?

Darryl Shaw
03-24-2009, 07:19 AM
The zone diet and athletic performance.

Cheuvront SN.

Department of Nutrition, Food, and Exercise Sciences, Florida State University, Tallahassee, USA.

The Zone diet is the latest eating regimen marketed to improve athletic performance by opposing traditional high carbohydrate sports diets. The 40/30/30 diet is centred primarily on protein intake (1.8 to 2.2 g/kg fat free mass; i.e. total bodyweight-fat weight) and promises a change in the body's insulin to glucagon ratio through its macronutrient alterations. Changes in the existing hormonal milieu are said to result in the production of more vasoactive eicosanoids, thus allowing greater oxygen delivery to exercising muscle. This favourable condition, known as the Zone, is anecdotally reported to benefit even the most elite endurance athletes. Applying the Zone's suggested protein needs and macronutrient distributions in practice, it is clear that it is a low carbohydrate diet by both relative and absolute standards, as well as calorie deficient by any standard. Reliable and abundant peer reviewed literature is in opposition to the suggestion that such a diet can support competitive athletic endeavours, much less improve them. The notion that a 40/30/30 diet can alter the pancreatic hormone response in favour of glucagon is also unfounded. The Zone is a mixed diet and not likely to affect pancreatic hormone release in the same way individual nutrients can. Although the postprandial insulin response is reduced when comparing a 40% with a 60% carbohydrate diet, it is still a sufficient stimulus to offset the lipolytic effects of glucagon. Many of the promised benefits of the Zone are based on selective information regarding hormonal influences on eicosanoid biology. Contradictory information is conveniently left out. The principle of vasodilating muscle arterioles by altering eicosanoid production is notably correct in theory. However, what little human evidence is available does not support any significant contribution of eicosanoids to active muscle vasodilation. In fact, the key eicosanoid reportedly produced in the Zone and responsible for improved muscle oxygenation is not found in skeletal muscle. Based on the best available scientific evidence, the Zone diet should be considered more ergolytic than ergogenic to performance.

http://www.ncbi.nlm.nih.gov/pubmed/10367332?ordinalpos=15&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum

You can also find a review of the Zone Diet in Clinical Sports Nutrition (3rd edition) by Louise Burke and Vicki Deakin (p.146-8, 475-6) but they reach the same conclusion as above ie. the Zone Diet is to low in calories and carbohydrates to be of any use to athletes and will in all probability have a detrimental effect on performance.

Mike ODonnell
03-24-2009, 07:31 AM
I'm not a fan of the Zone...but I know you can adjust blocks or whatever they call them to get higher intake of calories. A zone at a standard level is VERY low in calories....but you can make the calories high and keep the ratios. But...I don't do zone and like my carbs pwo. ANY diet too low in calories is not ideal for athletic performance....even high carbohydrate low calorie.

I'd be more interested in a study comparing diet protocols of the SAME amount of calories and different ratios of macroutrient intake rather than you using every thread as an opportunity to dismiss everything but a high carb diet as ideal.

Liam Dougherty Springer
03-24-2009, 11:46 AM
MOD- I know Evan personally and what he needs more than anything is articles/study reviews that are peer reviewed which show benefits of diets conducive to the use of stored energy during exertion. Basically something to combat the idea that food fuels the function and more that food refuels depletion.

I along with many came into my current dietary plan of “eat what my body asks for when it asks for it” through a Paleo/Zone/IF approach and then playing around from there. But today I realize while the zone is a way to open my metabolism to a more proper hormonal balance, eventually that just lead me to more appropriately listening to my body.

So I don't think this thread is best put in the Zone section however I understand why it has ended up here. Coach Glassman and crossfit in general adopting the Zone as a Rxed performance diet has put it on the front page so to speak. Now that Robb Wolff has so cunningly described a more appropriate and malleable dietary design and labeled it the athletes Zone we have a bunch of CFers claiming they zone while in fact they are just eating a well put together performance diet based on the idea of refueling and increasing nutrient delivery and utilization through natural metabolic function within the human, as a species.

So what I was hoping to find myself in this thread was some information involving the aid of insulin sensitivity through a reduced intake of highly digestible carbohydrate sources throughout the day and utilizing the glycogen preferred storage window for refueling as well as a fat adapted metabolism through increased caloric intake of healthy fats. Leading to a conclusion that functioning on stored fuel is more efficient than eating a power bar before getting to the gym and constantly sucking down HFCS water while working out.

I will also hopefully be turning the RD at my place of employment onto these references so the clients I refer to the lovely woman (and I really mean that she is awesome) will be in the hands of someone who is at least informed as to why I hold these opinions and thus state the requests of her that I do.

Thanx for the time and attention of any who give it,
Liam

Liam Dougherty Springer
03-24-2009, 11:52 AM
Oh yeah lets not beat the fact that the Zone as Dr. Sears has outlined is so low calorie as to make recovery and performance far from ideal for a few, and just dangrouse and impossible for the rest. That horse is at the foot of someones bed by now.:p

Donald Lee
03-24-2009, 12:42 PM
MOD- I know Evan personally and what he needs more than anything is articles/study reviews that are peer reviewed which show benefits of diets conducive to the use of stored energy during exertion. Basically something to combat the idea that food fuels the function and more that food refuels depletion.

I along with many came into my current dietary plan of “eat what my body asks for when it asks for it” through a Paleo/Zone/IF approach and then playing around from there. But today I realize while the zone is a way to open my metabolism to a more proper hormonal balance, eventually that just lead me to more appropriately listening to my body.

So I don't think this thread is best put in the Zone section however I understand why it has ended up here. Coach Glassman and crossfit in general adopting the Zone as a Rxed performance diet has put it on the front page so to speak. Now that Robb Wolff has so cunningly described a more appropriate and malleable dietary design and labeled it the athletes Zone we have a bunch of CFers claiming they zone while in fact they are just eating a well put together performance diet based on the idea of refueling and increasing nutrient delivery and utilization through natural metabolic function within the human, as a species.

So what I was hoping to find myself in this thread was some information involving the aid of insulin sensitivity through a reduced intake of highly digestible carbohydrate sources throughout the day and utilizing the glycogen preferred storage window for refueling as well as a fat adapted metabolism through increased caloric intake of healthy fats. Leading to a conclusion that functioning on stored fuel is more efficient than eating a power bar before getting to the gym and constantly sucking down HFCS water while working out.

I will also hopefully be turning the RD at my place of employment onto these references so the clients I refer to the lovely woman (and I really mean that she is awesome) will be in the hands of someone who is at least informed as to why I hold these opinions and thus state the requests of her that I do.

Thanx for the time and attention of any who give it,
Liam

Liam,

IMO, a lot of what you've stated is false. There's a happy medium between the extremes of Zoners/CrossFitters and the common bodybuilding-influenced nutrition knowledge.

For example, why would running on stored fuel be more efficient than eating a powerbar before working out? If in your workout, you end up depleting your glycogen, you would probably wish you had that powerbar pre-workout.

Just as training prescriptions are all relative to the goals, nutrition is also relative to people's goals.

And nutrition for general health is different from nutrition for sports performance.

Liam Dougherty Springer
03-24-2009, 01:22 PM
Liam,

IMO, a lot of what you've stated is false. There's a happy medium between the extremes of Zoners/CrossFitters and the common bodybuilding-influenced nutrition knowledge.

For example, why would running on stored fuel be more efficient than eating a powerbar before working out? If in your workout, you end up depleting your glycogen, you would probably wish you had that powerbar pre-workout.

Just as training prescriptions are all relative to the goals, nutrition is also relative to people's goals.

And nutrition for general health is different from nutrition for sports performance.


I almost made my already long post even longer by stating information dealing with what you just posted. I was honestly just hoping to find support for my opinions not begin a debate on apples and oranges and which is the better fruit. That being said I don't see were your post and mine are in any seriouse conflict.

If you are talking about endurance events in which you are required to have a long steady exertion of energy requiring a caloric output which far surpasses your glycogen storage then yes you are right you had better be fueling up as constantly with as easily digestible sources of energy as possible while exerting the energy. Outside of those events I stick to my opinions and I don't see where you are disagreeing. Even in those cases for health AND performance as stated in the original post and general metabolic function sticking to vegetables and some fruit as your primary source of carbohydrates and relying on them to restore glycogen rather than keep blood glucose available for energy would IMO be preferable. For this reason even the endurance athlete would do well to understand the legitimacy of the principles I stated above. So while we are both right it would still be nice to be able to present some information on the subject at hand being a healthy performance bias diet from my side as the majority of "general Knowledge" in the industry currently comes from the other.

I recognize that my comment as to the power bar was condescending and I do apologize if it offended anyone. I ate a cliff bar PWO just the other day, if it helps you feel better, I am not above a nutrient dense carb indulgence though I prefer pizza and ice cream.:D

Donald Lee
03-24-2009, 01:57 PM
This study might be useful, but it's for endurance athletes:

http://www.jacn.org/cgi/content/full/19/3/345


It has been shown that high CHO (60% to 70%) and low-fat (10% to 15%) diets enhance endurance performance, and high-fat diets (60%) are detrimental to performance. Athletes eating high-carbohydrate (low-fat) diets do not consume as many calories as they expend and may not meet the ADA levels of iron and zinc. Recent data, also, indicate that diets comprising 32% to 55% fat can improve endurance capacity compared to diets with 15% fat. There is evidence that fit subjects have higher fat oxidation due to increased enzyme levels, fatty acid transport and beta oxidation. In addition, intramuscular triglycerides and intracellular fats can be increased by a high-fat diet and can support higher levels of fat oxidation without compromising CHO stores. It is clear that if CHO intake is reduced to below 20% of total calories, or to less than 1.9 g/kg/day, glycogen stores are compromised and therefore performance will be compromised. Similarly, reducing fat intake to less than 20% of total calories compromises fat stores and therefore endurance performance.

It appears that a critical issue regarding the role of diet in exercise is that total caloric intake must be balanced to total caloric expenditure. Furthermore, the substrates consumed should replenish the intramuscular stores of the substrates used during training and competition. In trained athletes eating isocaloric diets that have sufficient levels of fats and CHOs (muscle stores), our data suggest that the blend of fats and CHOs used during exercise is set by the intensity of the exercise and is constant throughout the exercise time. Most scientists agree that a diet containing 15% to 20% protein calories is sufficient to meet the protein demands of most athletes. Thus a general isocaloric diet should comprise 30% to 35% CHOs, 30% fats and 20% protein, with the balance (20%) of total calories supplying the substrates used in training and competition. For competitions requiring exercise intensities of up to 85% of Vo2max, dietary fats may be more beneficial. For exercise intensities above 100% of Vo2max, CHOs would be the preferred macronutrient. The ratio of the intake of fats and carbohydrates to optimize performance for exercise between 80% to 100% Vo2max remains to be investigated.

Mike ODonnell
03-24-2009, 04:00 PM
depends on the sport....like all things above....what is the effort level, how long are the periods of exertion, etc. A pole vaulter and NFL running back would not be the same. For professional sports involving explosion over 30sec and < 2-3 min (glycolitic), they need glycogen....which needs to be already in the muscles. Now extend that over 2-3 hours like a hockey game and you bet your ass they will probably need some gatorade....but that's just during the game.

Liam Dougherty Springer
03-24-2009, 06:49 PM
depends on the sport....like all things above....what is the effort level, how long are the periods of exertion, etc. A pole vaulter and NFL running back would not be the same. For professional sports involving explosion over 30sec and < 2-3 min (glycolitic), they need glycogen....which needs to be already in the muscles. Now extend that over 2-3 hours like a hockey game and you bet your ass they will probably need some gatorade....but that's just during the game.

come on Mike I know you got some gold.... I am trying to find the study you posted a link to by a University in Texas about working out fasted

a post from Steven Low (I believe) a while back regarding the Metabolism's compromised ability to utilize glycogen and fat in the presence of insulin

Also something regarding the benefits as far as protein sparing and glycogen restoration efficiency due to insulin sensitivity. That would really solidify the argument for a diet different for training and game day for one. As you stated drink Gatorade when the player is exerting himself during the game as he sits on the bench during the longer (I know they are still short as far as digestion goes) breaks between plays for that particular player. Not all day every day.

No body is trying to insult anyone or hurt egos it just a want for information an a specific subject.

Darryl Shaw
03-25-2009, 06:35 AM
I'd be more interested in a study comparing diet protocols of the SAME amount of calories and different ratios of macroutrient intake rather than you using every thread as an opportunity to dismiss everything but a high carb diet as ideal.

http://www.ausport.gov.au/ais/nutrition/research/fat_adaptation

Liam Dougherty Springer
03-25-2009, 07:25 AM
http://www.ausport.gov.au/ais/nutrition/research/fat_adaptation

That study was actually pretty cool... If the information is taken out of the context of only endurance athletes the protocol would IMO look more like this.

Muscle glycogen stores should be kept at an optimal level for the energy requirements of the athlete. Based on those energy requirements the most efficient way to restore glycogen is immediately PWO with High GI nutrient dense sources along with protein in order to aid recovery. The full amount of carbohydrates should be consumed within the first two hours as the metabolism prefers muscle glycogen storage within the recovery window and this will enable increased recovery for the next WO. Increased intramuscular Triglyceride storage and usage has been shown to improve athletic performance and increase available energy so having a diet composed of 35-55% fat by calories is optimal for appropriate metabolic response. (I got some of that from the study Donald posted and keep in mind that WAS for endurance athletes)

I don't think any one here is saying the Atkins diet is best for marathon runners (I am not). Carbohydrates play an important roll in energy availability and recovery and need to be in an athletes diet. In APROPRIATE amounts.

Darryl Shaw
03-25-2009, 07:54 AM
Liam,

You might find this article on nutrient timing interesting.

International Society of Sports Nutrition position stand: Nutrient timing.

ABSTRACT

Position Statement: The position of the Society regarding nutrient timing and the intake of carbohydrates, proteins, and fats in reference to healthy, exercising individuals is summarized by the following eight points: 1.) Maximal endogenous glycogen stores are best promoted by following a high-glycemic, high-carbohydrate (CHO) diet (600 – 1000 grams CHO or ~8 – 10 g CHO/kg/d), and ingestion of free amino acids and protein (PRO) alone or in combination with CHO before resistance exercise can maximally stimulate protein synthesis. 2.) During exercise, CHO should be consumed at a rate of 30 – 60 grams of CHO/hour in a 6 – 8% CHO solution (8 – 16 fluid ounces) every 10 – 15 minutes. Adding PRO to create a CHO:PRO ratio of 3 – 4:1 may increase endurance performance and maximally promotes glycogen re-synthesis during acute and subsequent bouts of endurance exercise. 3.) Ingesting CHO alone or in combination with PRO during resistance exercise increases muscle glycogen, offsets muscle damage, and facilitates greater training adaptations after either acute or prolonged periods of supplementation with resistance training. 4.) Post-exercise (within 30 minutes) consumption of CHO at high dosages (8 – 10 g CHO/kg/day) have been shown to stimulate muscle glycogen re-synthesis, while adding PRO (0.2 g – 0.5 g PRO/kg/day) to CHO at a ratio of 3 – 4:1 (CHO: PRO) may further enhance glycogen re-synthesis. 5.) Post-exercise ingestion (immediately to 3 h post) of amino acids, primarily essential amino acids, has been shown to stimulate robust increases in muscle protein synthesis, while the addition of CHO may stimulate even greater levels of protein synthesis. Additionally, pre-exercise consumption of a CHO + PRO supplement may result in peak levels of protein synthesis. 6.) During consistent, prolonged resistance training, post-exercise consumption of varying doses of CHO + PRO supplements in varying dosages have been shown to stimulate improvements in strength and body composition when compared to control or placebo conditions. 7.) The addition of creatine (Cr) (0.1 g Cr/kg/day) to a CHO + PRO supplement may facilitate even greater adaptations to resistance training. 8.) Nutrient timing incorporates the use of methodical planning and eating of whole foods, nutrients extracted from food, and other sources. The timing of the energy intake and the ratio of certain ingested macronutrients are likely the attributes which allow for enhanced recovery and tissue repair following high-volume exercise, augmented muscle protein synthesis, and improved mood states when compared with unplanned or traditional strategies of nutrient intake.

http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=18834505

Liam Dougherty Springer
03-25-2009, 08:01 AM
Here is a study showing reduced Free Fatty Acid storage increases CHO usage durring energy expenditure.... so fat being used spares the glycogen.

http://www.ncbi.nlm.nih.gov/pubmed/12556353

I realise that past 100% VO2Max primarily if not solely glycogen will be used.

Liam Dougherty Springer
03-25-2009, 08:52 AM
Here is an interesting article haveing to do with pre exercise feeding once again dealing with indurence athletes but still interesting
http://www.springerlink.com/content/l15ur525556364tl/

Makes me wonder where equivalent energy came from in the placebo since there was no large difference in glycogen use. Seems to be consistent with the idea fat can buffer glycogen use I would be interested to see what happens down the road as the glucose levels drop further.

Steven Low
03-25-2009, 10:58 PM
Play around with PubMed some.

There's huge problems in most of the nutritional studies they do though so I wouldn't get your hopes up.

When they have people who are previously high carb do something like Zone.. they only have them do it for like 2 weeks which is not even enough time to adapt to the diet. Then they go and say something like "the participants on Zone had decreased performance and lack of energy." Well... no crap they had decreased energy... their bodies we're able to metabolize enough fat to sustain energy output yet. Dumb.

There's a lot of different stuff you're looking for in your OP... gotta be more specific what you're looking for. Performance + low carb..... vs. longevity + low carb.... and BTW, Zone isn't really low carb. I don't really know why stupid studies and people keep referring to it as low carb. Retarded.

Brian Stone
03-26-2009, 07:21 AM
P
.... and BTW, Zone isn't really low carb. I don't really know why stupid studies and people keep referring to it as low carb. Retarded.

I agree 100% here. I guess the carbs are low vs. the typical abysmal American standard, but by no means are they "low" overall at 40% of your macro intake. In fact, they're the largest macro consumed.

Liam Dougherty Springer
03-26-2009, 11:09 AM
Play around with PubMed some.

There's huge problems in most of the nutritional studies they do though so I wouldn't get your hopes up.

When they have people who are previously high carb do something like Zone.. they only have them do it for like 2 weeks which is not even enough time to adapt to the diet. Then they go and say something like "the participants on Zone had decreased performance and lack of energy." Well... no crap they had decreased energy... their bodies we're able to metabolize enough fat to sustain energy output yet. Dumb.
.


Agreed that is one of the things that got Evan started was that the people he works with sighted a study exactly like the one you have described....

Not about the zone but Steve do you have any studies about High carb feeding pre workout and the effects on fat metabolism durring exertion? or posibly performance?

The study i posted last infers there is no benifit to pre WO feeding as to performance during 30 min. run for highly trained runners. The thing I didn't like is the control group had a sweetened placibo in those not fed befor the exertion... Not ideal to have an insulin response to a no caloric beverage and then exert energy but still it was interesting to see that there was no advantage to the glucose and infact the fructose seemed to be the worst (though only marginaly).

Steven Low
03-26-2009, 12:25 PM
Nope, I don't have anything offhand. I haven't been saving nutritional studies unfortunately... most of the stuff I have been saving is related to exercise performance but not combined with nutrition.

In theory, stimulating the parasympathetic nervous system right before you need strong sympathetic activation for a workout/race is not a smart idea. AFAIK from experience and anecdotally, pre-workout anything food besides like BCAAs is not very beneficial... hence most of these "unofficial" results agreeing with the theory. Shrug.

Peri- and post workout nutrition is where all the money is going and rightfully should be because that's where the most "difference" is made. Then again, the difference also depends your goals.... PWO fasting is beneficial for things and PWO CHO/PRO is beneficial for others...

Liam Dougherty Springer
03-26-2009, 01:05 PM
Steve- Yeah I am in a similar boat... the reason I believe what I do is mostly through a broad range of studies and experience which cumulatively have provided me with intuition and self knowledge. The truth is I have a hard time with these subjects because we all are different on some level. Like you said when I put something together in my mind in a way that it makes since and then practicing it confirms my theory I consider it a truth, at least with respect to my own actions in life. Well for now the "general knowledge" prevails in institutionalized practice. Big Deal I can still act how I want and help those willing to try something different.

Darryl Shaw
06-20-2009, 04:44 AM
The Zone Diet Phenomenon: A Closer Look at the Science behind the Claims.

ABSTRACT.

The purported health benefits of low-carbohydrate diets have been advocated intermittently over the last century and have enjoyed increasing popularity over the last decade. Although most revolve around the emphatic theme that carbohydrates are to blame for many chronic diseases, their specific ideologies are more variable and in some cases quite sophisticated. The Zone Diet phenomenon represents a new generation of modern low carbohydrate food fad with sales placing it among the most popular diet books in recent history. The Zone is a 40% carbohydrate, 30% protein and 30% fat eating plan that advocates only sparing use of grains and starches. The precise 0.75 protein to carbohydrate ratio required with each meal is promoted to reduce the insulin to glucagon ratio, which purportedly affects eicosanoid metabolism and ultimately produces a cascade of biological events leading to a reduction in chronic disease risk, enhanced immunity, maximal physical and mental performance, increased longevity and permanent weight loss. There is presently little scientific support for the connections made between diet, endocrinology and eicosanoid metabolism. In fact, a review of the literature suggests that there are scientific contradictions in the Zone Diet hypothesis that cast unquestionable doubt on its potential efficacy. The purpose of this review is to evaluate the scientific merit of the Zone Diet and its health claims in an effort to help delineate what is and what is not sound nutrition science.

http://www.jacn.org/cgi/content/full/22/1/9

Steven Low
06-20-2009, 09:42 AM
The study is spot on considering there is no actual GOOD study of the Zone..... so of course there's no "real science" supporting it.

I still can't believe they call Zone a "low carb diet"

*facepalm*