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  1. #41
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    isnt it a proven fact that insulin increases protein synthesis?

    anyhow we know for a fact that insulin shuttles aminoacids into the muscles. That must have a positive effect on muscle growth(otherwise why would insulin shots be so efficent).

  2. #42
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    Quote Originally Posted by johan
    in essence I aggre with him that glycogen replenishment is not important. But one have to keep in mind that the "side effect" of creating a insulin cure is glycogen replenishment. They go hand in hand so his argument is bascily pointless..

    Either he thinks carbs are not important for muscle building and that is obviously wrong.(becasue of the insulin not the glycogen replenishment)

    OR

    He agres that insulin is needed for optimal muscle growth while saying that glycogen replenishemtn in itself is not the thing that makes the muscle grow. but it doesnt seem like he even considers insulin and even if he did that would be a self defeating argument since there is no way to create a sufficient insulin curve without carbs(if not injecting insulin without consuming carbs=hypoglycemia=possible death or consuming ENORMOUS ammounts of protein).

    I think he has gotten things confused(remember I havent read the whole thing since I stoped when he claims carbs are not essential for pwo nutrition).
    I see your point. And not that I am taking up for the guy because I have never heard of him nor tnation, but its a pretty good article with some nice references. Read it all the way through and see what you think.

  3. #43
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    I don't see anywhere where anything states that insulin increases protein synthesis, mainly glycogen syntheis. This should say everything:

    It is concluded that following a bout of heavy resistance training, MPS increases rapidly, is more than double at 24 hrs, and thereafter declines rapidly so that at 36 hrs it has almost returned to baseline.

  4. #44
    4U2NV is offline Associate Member
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    Quote Originally Posted by johan
    isnt it a proven fact that insulin increases protein synthesis?

    anyhow we know for a fact that insulin shuttles aminoacids into the muscles. That must have a positive effect on muscle growth(otherwise why would insulin shots be so efficent).
    Not sure about increase protein synthesis, but yes on its abililty to act as a shuttle.

  5. #45
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    then how do you explain the anabolic actions of insulin ? LIke I said Im not to knowlegable about that.

  6. #46
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    I'm sorry what I should have said is there is no relationship between rapid replenishment of glycogen and protein synthesis. Meaning a high GI might not be needed because all it does it replenish glycogen much quicker, but this does not translate into increased prtein synthesis!

  7. #47
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    You do need the presence of insulin to shuttle nutrients!

  8. #48
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    Physiologic hyperinsulinemia stimulates protein synthesis and enhances transport of selected amino acids in human skeletal muscle.
    G Biolo, R Y Declan Fleming, and R R Wolfe

    Department of Internal Medicine, University of Texas Medical Branch, Galveston.





    This article has been cited by other articles in PMC.
    Abstract
    We have investigated the mechanisms of the anabolic effect of insulin on muscle protein metabolism in healthy volunteers, using stable isotopic tracers of amino acids. Calculations of muscle protein synthesis, breakdown, and amino acid transport were based on data obtained with the leg arteriovenous catheterization and muscle biopsy. Insulin was infused (0.15 mU/min per 100 ml leg) into the femoral artery to increase femoral venous insulin concentration (from 10 +/- 2 to 77 +/- 9 microU/ml) with minimal systemic perturbations. Tissue concentrations of free essential amino acids decreased (P < 0.05) after insulin. The fractional synthesis rate of muscle protein (precursor-product approach) increased (P < 0.01) after insulin from 0.0401 +/- 0.0072 to 0.0677 +/- 0.0101%/h. Consistent with this observation, rates of utilization for protein synthesis of intracellular phenylalanine and lysine (arteriovenous balance approach) also increased from 40 +/- 8 to 59 +/- 8 (P < 0.05) and from 219 +/- 21 to 298 +/- 37 (P < 0.08) nmol/min per 100 ml leg, respectively. Release from protein breakdown of phenylalanine, leucine, and lysine was not significantly modified by insulin. Local hyperinsulinemia increased (P < 0.05) the rates of inward transport of leucine, lysine, and alanine, from 164 +/- 22 to 200 +/- 25, from 126 +/- 11 to 221 +/- 30, and from 403 +/- 64 to 595 +/- 106 nmol/min per 100 ml leg, respectively. Transport of phenylalanine did not change significantly. We conclude that insulin promoted muscle anabolism, primarily by stimulating protein synthesis independently of any effect on transmembrane transport.

    and doesnt a higher GI carb illicit a higher spike in insulin levels?

  9. #49
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    also keep in mind that BCAA is proven to prevent muscle protein breakdown. (ttp://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&li st_uids=15930473&query_hl=13.
    An anabolic effect of leucine and the branched-chain amino acids (BCAAs) on reduction of muscle protein breakdown was found in these studies,
    Insulin increases the shuttling of BCAA into the muscle.
    Since workouts itself are catabolic one have to stop the catabolic processes asap post workout to make room for the best possible growth. Alot of insulin will shuttle the BCAA and put a halt to muscle breakdown. By those means alone insulin is very important. Not to mention the BCAA creates anabolism(not dependant on protein synthesis so I might have been wrong about insulin and protein synthesis).

  10. #50
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    Quote Originally Posted by Alpha-Male
    Physiologic hyperinsulinemia stimulates protein synthesis and enhances transport of selected amino acids in human skeletal muscle.
    G Biolo, R Y Declan Fleming, and R R Wolfe

    Department of Internal Medicine, University of Texas Medical Branch, Galveston.





    This article has been cited by other articles in PMC.
    Abstract
    We have investigated the mechanisms of the anabolic effect of insulin on muscle protein metabolism in healthy volunteers, using stable isotopic tracers of amino acids. Calculations of muscle protein synthesis, breakdown, and amino acid transport were based on data obtained with the leg arteriovenous catheterization and muscle biopsy. Insulin was infused (0.15 mU/min per 100 ml leg) into the femoral artery to increase femoral venous insulin concentration (from 10 +/- 2 to 77 +/- 9 microU/ml) with minimal systemic perturbations. Tissue concentrations of free essential amino acids decreased (P < 0.05) after insulin. The fractional synthesis rate of muscle protein (precursor-product approach) increased (P < 0.01) after insulin from 0.0401 +/- 0.0072 to 0.0677 +/- 0.0101%/h. Consistent with this observation, rates of utilization for protein synthesis of intracellular phenylalanine and lysine (arteriovenous balance approach) also increased from 40 +/- 8 to 59 +/- 8 (P < 0.05) and from 219 +/- 21 to 298 +/- 37 (P < 0.08) nmol/min per 100 ml leg, respectively. Release from protein breakdown of phenylalanine, leucine, and lysine was not significantly modified by insulin. Local hyperinsulinemia increased (P < 0.05) the rates of inward transport of leucine, lysine, and alanine, from 164 +/- 22 to 200 +/- 25, from 126 +/- 11 to 221 +/- 30, and from 403 +/- 64 to 595 +/- 106 nmol/min per 100 ml leg, respectively. Transport of phenylalanine did not change significantly. We conclude that insulin promoted muscle anabolism, primarily by stimulating protein synthesis independently of any effect on transmembrane transport.

    and doesnt a higher GI carb illicit a higher spike in insulin levels?
    Thanks bro posted before I read this one

    So insulin not only increases protein synthesis it also shuttles BCAA that is in turn anabolic and prevents muscle protein breakdown. A dubble whammy to create muscle growth in other words and high gi carbs is the most efficent(gram for gram)to release insulin.

    I dont se any way to debate this

  11. #51
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    This abstract deals with insulin that is infused:
    Insulin was infused (0.15 mU/min per 100 ml leg) into the femoral artery to increase femoral venous insulin concentration (from 10 +/- 2 to 77 +/- 9 microU/ml) with minimal systemic perturbations.

    So there is very little corelation to the other studies.

  12. #52
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    Quote Originally Posted by Giantz11
    This abstract deals with insulin that is infused:
    Insulin was infused (0.15 mU/min per 100 ml leg) into the femoral artery to increase femoral venous insulin concentration (from 10 +/- 2 to 77 +/- 9 microU/ml) with minimal systemic perturbations.

    So there is very little corelation to the other studies.


    besides ammount. what difference is there with syntethic injected insulin and naturaly releases insulin. The protein chain as far as I know is identic so the body wouldnt know the difference

  13. #53
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    Quote Originally Posted by Giantz11
    This abstract deals with insulin that is infused:
    Insulin was infused (0.15 mU/min per 100 ml leg) into the femoral artery to increase femoral venous insulin concentration (from 10 +/- 2 to 77 +/- 9 microU/ml) with minimal systemic perturbations.

    So there is very little corelation to the other studies.
    personally, i dont see how that matters, it was simply to increase total insulin concentration...why would that make a difference?

  14. #54
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    Because you body doesn't produce does not nautrally produce enough insulin to take care of this, hence the reason bodybuilders use insulin. Because it is indeed anabolic but you cannot produce enough you self do this. Insulin increases permeability in glut4 recpetors helping increase nutrient uptake during normal feeding patterns, however weight training does this for you as well, so why the massive spike?

  15. #55
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    also reading a bit more now he thinks a solid meal is better pwo and qoutes a studie showing a shake taken 1 hour after workout beeing better then imidietly after.

    but the pwo protocol we recomend is pwo shake imidietly and ppwo meal 1 hour after. that inclueds the best of all worlds if Im not mistaken.

  16. #56
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    Liu Z, Jahn LA, Wei L, Long W, Barrett EJ.

    Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Virginia Health Sciences Center, Charlottesville, Virginia 22908, USA. [email protected]

    Studies in vitro as well as in vivo in rodents have suggested that amino acids (AA) not only serve as substrates for protein synthesis, but also as nutrient signals to enhance mRNA translation and protein synthesis in skeletal muscle. However, the physiological relevance of these findings to normal humans is uncertain. To examine whether AA regulate the protein synthetic apparatus in human skeletal muscle, we infused an AA mixture (10% Travesol) systemically into 10 young healthy male volunteers for 6 h. Forearm muscle protein synthesis and degradation (phenylalanine tracer method) and the phosphorylation of protein kinase B (or Akt), eukaryotic initiation factor 4E-binding protein 1, and ribosomal protein S6 kinase (p70(S6K)) in vastus lateralis muscle were measured before and after AA infusion. We also examined whether AA affect urinary nitrogen excretion and whole body protein turnover. Postabsorptively all subjects had negative forearm phenylalanine balances. AA infusion significantly improved the net phenylalanine balance at both 3 h (P < 0.002) and 6 h (P < 0.02). This improvement in phenylalanine balance was solely from increased protein synthesis (P = 0.02 at 3 h and P < 0.003 at 6 h), as protein degradation was not changed. AA also significantly decreased whole body phenylalanine flux (P < 0.004). AA did not activate Akt phosphorylation at Ser(473), but significantly increased the phosphorylation of both eukaryotic initiation factor 4E-binding protein 1 (P < 0.04) and p70(S6K) (P < 0.001). We conclude that AA act directly as nutrient signals to stimulate protein synthesis through Akt-independent activation of the protein synthetic apparatus in human skeletal muscle.

  17. #57
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    Quote Originally Posted by Giantz11
    Because you body doesn't produce does not nautrally produce enough insulin to take care of this, hence the reason bodybuilders use insulin. Because it is indeed anabolic but you cannot produce enough you self do this. Insulin increases permeability in glut4 recpetors helping increase nutrient uptake during normal feeding patterns, however weight training does this for you as well, so why the massive spike?
    I wouldnt know about that since I have no clue how much insulin is released naturaly when compered to injecting. In other words how many iu of for instance humalog would the natural peak comperable with.

    offcourse insuline sensitivity ect plays a big part in that but maby someone knows a rough number(when consuming 100g dextrose as natural spike method)

  18. #58
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    Listen, I currenly use dextrose and follow the same plan as many people here. just playing Devils Advocate that's all!

  19. #59
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    Quote Originally Posted by Giantz11
    Liu Z, Jahn LA, Wei L, Long W, Barrett EJ.

    Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Virginia Health Sciences Center, Charlottesville, Virginia 22908, USA. [email protected]

    Studies in vitro as well as in vivo in rodents have suggested that amino acids (AA) not only serve as substrates for protein synthesis, but also as nutrient signals to enhance mRNA translation and protein synthesis in skeletal muscle. However, the physiological relevance of these findings to normal humans is uncertain. To examine whether AA regulate the protein synthetic apparatus in human skeletal muscle, we infused an AA mixture (10% Travesol) systemically into 10 young healthy male volunteers for 6 h. Forearm muscle protein synthesis and degradation (phenylalanine tracer method) and the phosphorylation of protein kinase B (or Akt), eukaryotic initiation factor 4E-binding protein 1, and ribosomal protein S6 kinase (p70(S6K)) in vastus lateralis muscle were measured before and after AA infusion. We also examined whether AA affect urinary nitrogen excretion and whole body protein turnover. Postabsorptively all subjects had negative forearm phenylalanine balances. AA infusion significantly improved the net phenylalanine balance at both 3 h (P < 0.002) and 6 h (P < 0.02). This improvement in phenylalanine balance was solely from increased protein synthesis (P = 0.02 at 3 h and P < 0.003 at 6 h), as protein degradation was not changed. AA also significantly decreased whole body phenylalanine flux (P < 0.004). AA did not activate Akt phosphorylation at Ser(473), but significantly increased the phosphorylation of both eukaryotic initiation factor 4E-binding protein 1 (P < 0.04) and p70(S6K) (P < 0.001). We conclude that AA act directly as nutrient signals to stimulate protein synthesis through Akt-independent activation of the protein synthetic apparatus in human skeletal muscle.
    how does that show that insulin wont increase that protein synthesis(by shuttling more amino acids into the muscle).?

  20. #60
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    Quote Originally Posted by Giantz11
    Listen, I currenly use dextrose and follow the same plan as many people here. just playing Devils Advocate that's all!
    yes just a friendly debate. I have to admit I am way short on my medical knoweledge to be able to fully comprehend all these studies. I usualy go by the conclusion and try to understand the rest so many of my own conclusion might be flawed because of my lack of general knoweledge about biochemistry.

  21. #61
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    what would 100g of dextrose/malto spike your insuln levels to? we would need to know that to answer your questions, but also, we would need to compare levels of protein synthesis from both studies, to see which yields more...

  22. #62
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    I just pm'ed hooker to se if he knows the answere to the natural ammount of insulin compered to injected.

  23. #63
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    either of you guys read the book Nutrient Timing? if not, check it out, id like to discuss it here...

  24. #64
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    never heard of it. Who is the author(the swedish title is probably different so need authors name to find it here). by the way do you have it on pdf?

  25. #65
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    http://www.amazon.com/exec/obidos/tg...glance&s=books

    of course, you dont have to buy it there, i just googled it cuz it's at home and im still at the office...sorry, no pdf

  26. #66
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    A few points about the insulin spikes:

    30-60 Post exercise is insulin independant. So consuming a Hi GI carb will rapidly replensish glycogen yes, but has no effect on protein synthesis. In fact Protein synthesis peaks out at 24hr post exercise.

    Here's an alarming statement however:
    A large part of the ingested glucose that enters the bloodstream appears to be extracted by tissues other than the exercise muscle (i.e. liver, other muscle groups or fat tissue) and may therefore limit the amount of glucose available to maximise muscle glycogen synthesis rates. Furthermore, intestinal glucose absorption may also be a rate-limiting factor for muscle glycogen synthesis when large quantities (&gt;1 g/min) of glucose are ingested following exercise.

  27. #67
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    just out of curiosity. What kind of education do you have giantz11 you seem to know alot!

  28. #68
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    I've done low gi pwo and high gi pwo.

    I find that with high gi pwo I look far better, recovery is better, I get stronger, etc., etc. This is what I've found to work for me.

    In my biz, those I instruct I have them on high gi pwo, and they do very well also, so I won't be changing anything there. A few diabetics I have on low gi carbs pwo AND at all other times, but there is a rhyme/reason for that as well.

    So, my answer to all this is simply, "find what works best for you", and continue to do that, as that is all that really matters in the big scheme of things.

    Enjoy!

    ~SC~

  29. #69
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    lol but that is so boringly unscientific

  30. #70
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    Some things are best left that way!

    Honestly, I've seen articles/write-ups like this on BOTH sides of the issue for the last 5 years.

    I mean, magazines have to have SOMETHING to write about to stir up interest, right?

    Supplements are a big biz!

    ~SC~

  31. #71
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    "The highest muscle glycogen synthesis rates have been reported when large amounts of carbohydrate (1.0-1.85 g/kg/h) are consumed immediately post-exercise and at 15-60 minute intervals thereafter, for up to 5 hours post-exercise."

    "The addition of certain amino acids and/or proteins to a carbohydrate supplement can increase muscle glycogen synthesis rates, most probably because of an enhanced insulin response."

    taken from your studies...

  32. #72
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    Quote Originally Posted by SwoleCat
    Some things are best left that way!

    Honestly, I've seen articles/write-ups like this on BOTH sides of the issue for the last 5 years.

    I mean, magazines have to have SOMETHING to write about to stir up interest, right?

    Supplements are a big biz!

    ~SC~
    True. Im crazy addicted to info though so I always have this urge to find out exactly why something works or doesnt work

  33. #73
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    yeah, in the end, Swole's right...the difference that is actually realized in gains from one person to the next, utilizing all these different protocols, is probably minimal at best...i think we've got a pretty good handle on the basics, and honestly, results speak so much louder than any study i've ever read...and damn, SC is blown up, so he's obviously gotta hold on what works, eh? still, im with Johan too, i like to debate, and it's fun to research, especially when im bored up at work

  34. #74
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    yeah no doubt that swole knows what works

  35. #75
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    Yeah being bored at work is basically what startwed this whole thing....Swole is right find what works for you....And another point that hasn't been made is that dammit Dex tastes so friggin good....However there does seem to be some evidence that a Low GI approach could work, so in the future I may give it a try because quitre simply consuming whole grains and complex carbs will always be more beneficial....Johan I have taken nutrition in college but nothing to advanced however recently i've been reading alot of physiology texts, books etc....Once I got back into nutrition I've just been doing alot of research and reading....I guess I should be doing more work in the office but this is far more fun!!!

  36. #76
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    resurecting a old thread lol. A article about high vs low gi carbs on muscle glycogen replenishment. This ISNT pwo though

    http://www.ncbi.nlm.nih.gov/entrez/q...796&query_hl=7

    Ingestion of a high glycemic index meal increases muscle glycogen storage at rest but augments its utilisation during subsequent exercise.

    Wee SL, Williams C, Tsintzas K, Boobis L.

    School of Sport and Exercise Sciences, Loughborough University, Loughborough, United Kingdom.

    The aim of this study was to compare the effect of pre-exercise breakfast containing high and low glycemic index (GI) carbohydrate (CHO) (2.5g CHO/kg body mass) on muscle glycogen metabolism. On two occasions, 14 days apart, seven trained men ran at 71%VO2 max for 30 min on a treadmill. Three hours before exercise, in a randomised order, subjects consumed either isoenergetic high (HGI) or low (LGI) GI CHO breakfasts providing (per 70 kg body mass): 3.43 MJ energy, 175g CHO, 21g protein and 4g fat. The incremental areas under the 3 h plasma glucose and serum insulin response curves after the HGI meal were 3.9- (P < 0.05) and 1.4-fold greater (P < 0.001) respectively, than that after the LGI meal. During the 3 h postprandial period, muscle glycogen concentration increased by 15% (P < 0.05) following the HGI meal but remained unchanged after the LGI meal. Muscle glycogen utilisation during exercise was greater in the HGI [129.1 +/- 16.1 mmol/kg dry mass (dm)] compared to the LGI (87.9 +/- 15.1 mmol/kg dm, P<0.01) trial. Although the LGI meal contributed less CHO to muscle glycogen synthesis in the 3 h postprandial period compared to the HGI meal, a sparing of muscle glycogen utilisation during subsequent exercise was observed in the LGI trial, most likely as a result of better maintained fat oxidation.

    PMID: 15831796 [PubMed - as supplied by publisher]

    full text can be found here
    http://www.ncbi.nlm.nih.gov/entrez/u...&pmid=15831796

    since this was pre workout it shows that the body uses more carbs during a workout when it gets high gi carbs pre workout compered to low gi carbs.

  37. #77
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    [QUOTE=Giantz11]A few points about the insulin spikes:

    30-60 Post exercise is insulin independant. So consuming a Hi GI carb will rapidly replensish glycogen yes, but has no effect on protein synthesis. In fact Protein synthesis peaks out at 24hr post exercise.

    QUOTE]

    only true for muscle glycogen synthesis, not protein synthesis...

    "It has been suggested that muscle glycogen synthesis after glycogendepleting
    exercise occurs in two phases (Price et al. 1994). Initially, there is a
    period of rapid synthesis of muscle glycogen that does not require the presence
    of insulin and lasts approximately 30-60 min (Jentjens et al. 2001). This early
    post-exercise recovery period is marked by an exercise-induced permeability of
    the muscle cell membrane to glucose (Jentjens et al. 2001)."

    unless you can post otherwise...

  38. #78
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    I do not debate that abstract in fact I was the one who posted it....It says that glycogen replenishment is insulin independant for 30-60 minutes, yes. But what happens if you do spike insulin, it most certainly will replenish glycogen faster.

  39. #79
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    no, you said it has no effect on PROTEIN synthesis...

  40. #80
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    The abstract you posted deals with glycogen synthesis!

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