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  1. #41
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    Don't forget, that the study above was in recreational bodybuilders -- much more applicable to our type of people than the average study.

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    Quote Originally Posted by dashforce' post='462160' date='Feb 28 2008, 05:13 PM
    Don't forget, that the study above was in recreational bodybuilders -- much more applicable to our type of people than the average study.


    True, but I wish they would do one of these studies right for a change.



    For purposes of complete-ness: the 0.68 g/lb of protein supplement was divided breakfast, lunch, dinner, and PWO. Missed that on the first read through.



    ---------------



    Elapsed time between feeding and appearance of leucine/aminos in serum would be a fair measure of rate of intestinal absorption, right? There's data on this, but apparently no direct measure of intestinal transport of aminos.

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    (From the last study we have hydro-whey beating out casein.)



    All this has led me right back to where I started - that a mix of slow and fast proteins are best both after training and at rest. Whether it's casein + whey or casein + hydro-whey, don't see it making much of a difference.



    I could not find leucine appearance data following a workout in trained subjects, but the study from Strength and Conditioning Research makes it a moot point.



    ------------------------------------------



    Data on appearance of Leucine without prior workout below. Data on leucine appearance after training was not found.



    Whey increases protein synthesis; casein decreases breakdown.



    Young subjects ingest 30g whey or 40g casein after 10 hour fast, no workout beforehand although normal exercise and diet was maintained in days before the study.



    Casein with 382 micro-mol leucine per kg



    Leucine elevated 77%+-24% @ 100 minutes and 61%+-30% at 300 minutes



    Whey with 380 micro-mol leucine per kg



    Leucine elevated 236% +- 56% at 100 minutes and 29%+-11%



    -----------------------



    Slow and fast dietary proteins differently modulate postprandial protein accretion

    Proc. Natl. Acad. Sci. USA Vol. 94, pp. 14930–14935, December 1997



    Postprandial amino acid increases over baseline were identical whether the proteins were labeled or not. Those increases were different between CAS and WP (Table 2). The two protein meals were matched for leucine content but were not isonitrogenous, and amino acid intake was higher with CAS. Despite this higher amino acid intake, amino acid concentrations increased less with CAS than with WP at 100 min. By contrast, at 300 min, most amino acids remained at higher concentrations with CAS whereas they returned to basal levels with WP. These two particular plasma amino acid profiles also are illustrated by leucine concentration determined at each time point in Fig. 2A.



    Plasma insulin levels similarly increased after both meals. The values were, at 0, 40, and 300 min, 6.2 6 2.4, 16.8 6 12.8, and 6.3 6 3.4 microU/ml, and 7.5 6 1.3, 19.8 6 5.3, and 6.1 6 1.4 microU/ml for CAS and WP, respectively. Note: In the whey group, protein breakdown still occurs even when insulin is elevated.)



    Total NOLD (i.e., total protein synthesis) was stimulated by 68% and 31% (average from 40 to 140 min) with WP and CAS, respectively, the difference between the two diets being not significant although there was a trend for a higher protein synthesis with WP.



    Under the conditions of this study, i.e., a single protein meal with no energy added, two dietary proteins have different metabolic fates and uses. After WP ingestion, the plasma appearance of dietary amino acids is fast, high, and transient. This amino acid pattern is associated with an increased protein synthesis and oxidation and no change in protein breakdown. By contrast, the plasma appearance of dietary amino acids after a CAS meal is slower, lower, and prolonged with a different whole body metabolic response: Protein synthesis slightly increases, oxidation is moderately stimulated, but protein breakdown is markedly inhibited. The latter metabolic profile results in a better leucine balance.



    In the next study, whey + casein beats out whey, even when BCAAs and glutamine are added to the whey. Now, there's no data on casein + whey vs. hydro-whey or vs casein + hydro-whey. Think it's safe to assume that if mix of fast and slow is best, casein and hydro-whey would be better than hydro-whey alone.



    Journal of Strength and Conditioning Research, 2006, 20(3), 643–653 _ 2006 National Strength & Conditioning Association



    THE EFFECTS OF PROTEIN AND AMINO ACID SUPPLEMENTA ION ON PERFORMANCE AND TRAINING ADAPTATIONS DURING TEN WEEKS OF RESISTANCE TRAINING



    ABSTRACT. The purpose of this study was to examine the effects of whey protein supplementation on body composition, muscular strength, muscular endurance, and anaerobic capacity during 10 weeks of resistance training. Thirty-six resistance-

    trained males
    (31.0 _ 8.0 years, 179.1 _ 8.0 cm, 84.0 _ 12.9 kg, 17.8 _ 6.6%) followed a 4 days-per-week split body part resistance training program for 10 weeks. Three groups of supplements were randomly assigned, prior to the beginning of the exercise program, in a double-blind manner to all subjects: 48 g per day carbohydrate placebo (P), 40 of whey protein and 8 g/day of casein (WC), or 40 g/d of whey protein, 3 g/day branched-chain amino acids, and 5 g/day L-glutamine (WBG). At 0, 5, and 10 weeks, subjects were tested for fasting blood samples, body mass, body composition using dual-energy x-ray absorptiometry (DEXA), 1 repetition maximum (1RM) bench and leg press, 80% 1RM maximal repetitions to fatigue for bench press and leg press, and 30-second Wingate anaerobic capacity tests. No changes ( p _ 0.05) were noted in all groups for energy intake, training volume, blood parameters, and anaerobic capacity. WC experienced the greatest increases in DEXA lean mass (P _ 0.0 _ 0.9; WC _ 1.9 _ 0.6; WBG _ _0.1 _ 0.3 kg, p _ 0.05) and DEXA fat-free mass (P _ 0.1 _ 1.0; WC _ 1.8 _ 0.6; WBG _ _0.1 _ 0.2 kg, p _ 0.05). Significant increases in 1RM bench press and leg press were observed in all groups after 10 weeks. In this study, the combination of whey and casein protein promoted the greatest increases in fat-free mass after 10 weeks of heavy resistance training. Athletes, coaches, and nutritionists can use these findings to increase fat-free mass and to improve body composition during resistance training.







    If anyone has data on casein + whey vs. casein + hydro-whey, that would seal the deal.

  4. #44
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    Quote Originally Posted by Heavy_Lifter85' post='462175' date='Feb 28 2008, 05:22 PM
    Elapsed time between feeding and appearance of leucine/aminos in serum would be a fair measure of rate of intestinal absorption, right? There's data on this, but apparently no direct measure of intestinal transport of aminos.


    Perhaps. Imagine a transport mechanism for certain aminos (for example) that acted quickly, but was easily saturated. In this case, time would be a poor indicator, because although the appearance might be near instantaneous, if the system is saturated at 1g/hr, it's not doing much.



    Different aminos will have different absorption kinetics, I would assume (not sure about intestinal, but for example intracellular BCAAs are transported by system L don't seem to have any factors that increase the rate of transport, whereas other transport mechanisms for other aminos use a Na+ antiport system that can be manipulated I assume).

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    Quote Originally Posted by dashforce' post='462041' date='Feb 28 2008, 10:29 AM
    EDIT: And that [meat] study just says "fast protein" without including any numbers -- do you have the FT? Can we get numbers so as to compare with whey/casein/isolates/hydrolysates?


    Looking at the graphs for leucine appearance after meat, whey, and casein ingestion - meat spikes leucine like whey for the first two hours but keeps leucine elevated for four hours like casein does. i.e. meat mimics a mix of casein and whey.



    I am reminded of the study concluding that milk is as effective as casein + whey. Might the same be seen with beef?

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    Quote Originally Posted by dashforce' post='462202' date='Feb 28 2008, 07:35 PM
    "Elapsed time between feeding and appearance of leucine/aminos in serum would be a fair measure of rate of intestinal absorption, right?"



    Perhaps.


    Damn, I might have saved myself an hour or so of research.



    Well, absoption kinetics and transporters should make for interesting reading ... at a later date. Lost is coming on soon - brain is turning off.

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    you are forgetting something - digestion issues (esp. post workout)
    Man on a mission

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    Posted this in the wrong thread last night



    Casein + whey for the win! (On basis of taste and price over hydro-whey)



    No difference between intestinal absorption speed of hydro-whey vs. whey.



    ---------------------------------------------------



    Gastric emptying, gastric secretion and enterogastrone response after administration of milk proteins or their peptide hydrolysates in humans



    Abstract:

    The influence of protein fractionation on gastric emptying and rate of appearance of their constituent amino acids in peripheral blood remains unknown.



    To examine the influence of the degree of protein fractionation on gastric emptying, gastric secretion, amino acid absorption and enterogastrone response, after the intragastric administration of complete cow milk proteins or their respective peptide hydrolysates in man.



    Six healthy males were randomized to receive one of the following four solutions: whey whole protein (W), casein whole protein ©, whey peptide hydrolysate (WHY) or casein hydrolysate (CAHY). All solutions were matched for volume (600 mL), nitrogen content (9.3 g/L), energy density (1069–1092 kJ/L), osmolality (288–306 mosmol/kg), pH (6.9–7.0) and temperature (37 °C).



    Solutions were emptied at similar rates, with mean half-times of (mean ± SEM) 21.4 ± 1.3, 19.3 ± 2.2, 18.0 ± 2.5 and 19.4 ± 2.8 min, for the WHY, CAHY, C and W, respectively. The rates of intestinal absorption of water and amino acids were similar with the exception of the casein protein solution, for which the speed of intestinal amino acid absorption was slower (p < 0.05). The peptide hydrolysates elicited about 50% more gastric secretion than the whole protein solutions (p < 0.05),which was accompanied by higher glucosedependent insulinotropic polipeptide (GIP) plasma levels during the first 20 min of the gastric emptying process. Similar glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) plasma responses were elicited by the four solutions.



    The rate of gastric emptying and the plasma GLP-1 and PYY responses to feeding with cow milk protein solutions in humans are independent of the degree of protein fractionation and are not altered by small differences in the amino acid composition or protein solubility. In contrast, the GIP response is accentuated when milk proteins are delivered as peptide hydrolysates.



    ---------------------------------------------



    In The Protein Book, Lyle suggests that, barring mass consumption of a single amino acid, transporter saturation/competition is unlikely. Also, intestinal absorption rates are given for a few protein sources: (in g/hr)



    Cooked egg 2.9

    Milk protein 3.5

    Casein 6.1

    Whey isolate 8-10

    Pork tenderloin 10 (!)



    Finally, references suggesting that high protein consumption will lead to faster digestion and absorption over time are given.

  9. #49
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    Quote Originally Posted by Heavy_Lifter85' post='462205 View Post
    you are forgetting something - digestion issues (esp. post workout)
    ?? As in SNS stops gastric motility? Isn't this avoided by ingesting free aminos, which can be absorbed directly?



    Quote Originally Posted by Heavy_Lifter85' post='462275' date='Feb 29 2008, 04:04 AM
    Finally, references suggesting that high protein consumption will lead to faster digestion and absorption over time are given.


    In the big picture, is this good? Referring to the OP's suggestion that fast PROs also switch on increased oxidation, resulting in a lower overall N balance?



    Fast PRO is great PWO, when we have that small window in trained individuals, but at other times we want casein-type stuff, right?

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    Quote Originally Posted by dashforce' post='462378' date='Feb 29 2008, 03:10 PM
    "Finally, references suggesting that high protein consumption will lead to faster digestion and absorption over time are given." In the big picture, is this good?



    It seems to suggest that the 'ceiling' on protein consumption can be raised.



    Referring to the OP's suggestion that fast PROs also switch on increased oxidation, resulting in a lower overall N balance?

    Fast PRO is great PWO, when we have that small window in trained individuals, but at other times we want casein-type stuff, right?


    Slow types inhibit protein breakdown with minimal impact on synthesis. Fast types stimulate synthesis regardless of when they are consumed, but have a marginal impact on breakdown. Clearly, there is a need for both, both PWO and at regular mealtimes.



    Another issue:



    Meal frequency - A high frequency may 'desensitize' the muscles to presence of aminos, retarding protein synthesis. The change in levels of extracellular aminos seems to be the trigger for synthesis. However, EAAs between meals are seemingly still effective for initiation of protein synthesis.



    The conclusions I reach are: Eat 3 - 4 meals per day, getting fast and slow proteins at each (or something like beef that has properties of both). Use whey before and during the workout and whey + casein after. If money is no object, try EAA's between meals.

  11. #51
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    Quote Originally Posted by dashforce' post='462378' date='Feb 29 2008, 02:10 PM
    ?? As in SNS stops gastric motility? Isn't this avoided by ingesting free aminos, which can be absorbed directly?
    yes
    Man on a mission

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    Quote Originally Posted by Heavy_Lifter85' post='462437' date='Feb 29 2008, 05:20 PM
    Meal frequency - A high frequency may 'desensitize' the muscles to presence of aminos, retarding protein synthesis. The change in levels of extracellular aminos seems to be the trigger for synthesis. However, EAAs between meals are seemingly still effective for initiation of protein synthesis.


    You're referring to the IV study where hyperaminoacidemia elicited PRO synthese for a while, followed by a refractory period? I wonder what regulates that refractory period -- exhaustion of some intermediate?

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    Quote Originally Posted by dashforce' post='462624' date='Mar 1 2008, 08:11 PM
    You're referring to the IV study where hyperaminoacidemia elicited PRO synthese for a while, followed by a refractory period? I wonder what regulates that refractory period -- exhaustion of some intermediate?


    Yep, that's the one:



    Journal of Physiology (2001), 532.2, pp. 575-579

    Latency and duration of stimulation of human muscle protein synthesis during continuous infusion of amino acids



    The aim of this study was to describe the time course of the response of human muscle protein synthesis (MPS) to a square wave increase in availability of amino acids (AAs) in plasma. We investigated the responses of quadriceps MPS to a ~1.7-fold increase in plasma AA concentrations using an intravenous infusion of 162 mg (kg body weight)-1 h-1 of mixed AAs. MPS was estimated from D3-leucine labelling in protein after a primed, constant intravenous infusion of D3-ketoisocaproate, increased appropriately during AA infusion.



    Muscle was separated into myofibrillar, sarcoplasmic and mitochondrial fractions. MPS, both of mixed muscle and of fractions, was estimated during a basal period (2.5 h) and at 0.5-4 h intervals for 6 h of AA infusion.



    Rates of mixed MPS were not significantly different from basal (0.076 ± 0.008 % h-1) in the first 0.5 h of AA infusion but then rose rapidly to a peak after 2 h of ~2.8 times the basal value. Thereafter, rates declined rapidly to the basal value. All muscle fractions showed a similar pattern.



    The results suggest that MPS responds rapidly to increased availability of AAs but is then inhibited, despite continued AA availability. These results suggest that the fed state accretion of muscle protein may be limited by a metabolic mechanism whenever the requirement for substrate for protein synthesis is exceeded.



    -----------------------------------------



    Latency, Duration and Dose Response Relationships of Amino Acid Effects on Human Muscle Protein Synthesis



    The components of the stimulatory effect of food on net deposition of protein are beginning to be identified and separated. One of the most important of these appears to be the effect of amino acids per se in stimulating muscle anabolism. Amino acids appear to have a linear stimulatory effect within the range of normal diurnal plasma concentrations from postabsorptive to postprandial. Within this range, muscle protein synthesis (measured by incorporation of stable isotope tracers of amino acids into biopsied muscle protein) appears to be stimulated approximately twofold; however, little further increase occurs when very high concentrations of amino acids (>2.5 times the normal postabsorptive plasma concentration) are made available. Amino acids provided in surfeit of the ability of the system to synthesize protein are disposed of by oxidation, ureagenesis and gluconeogenesis. The stimulatory effect of amino acids appears to be time dependent; a square wave increase in the availability of amino acids causes muscle protein synthesis to be stimulated and to fall back to basal values, despite continued amino acid availability. The relationship between muscle protein synthesis and insulin availability suggests that most of the stimulatory effects occur at low insulin concentrations, with large increases having no effect. These findings may have implications for our understanding of the body’s requirements for protein. The maximal capacity for storage of amino acids as muscle protein probably sets an upper value on the extent to which amino acids can be stored after a single meal.



    ---------------------------------------------------------------------



    Check the full texts for more insight from the authors.



    When is sensitivity to amino acids restored?



    With an X g feeding of whey protein, serum AA levels reach baseline about X/10 hours after ingestion.



    After AA infusion, protein synthesis stops after about two hours; insulin falls from the 75 - 50 microUI/liter range in the same timeframe



    Only 20 - 25g of complete protein is needed to stimulate protein synthesis maximally.



    So 20g whey feedings every 2 -3 hours might work well. Spike AA/insulin/synthesis, allow to fall to base line, repeat. Follow the workout with a substantial meal of fast and slow proteins to provide AA overnight.



    Note this scheme would produce a protein intake similar to that advocated in the original post, but oxidation of excess AA's might be avoided with small, repeated feedings.



    Would addition of small amount of casein to whey feedings prevent return to baseline/sensitivity?

    --------------------------------------------------------------------



    Unrelated. More grist for the mill:





    Journal of Science and Medicine in Sport

    Volume 4, Issue 4, December 2001, Pages 431-446



    Influence of weight training exercise and modification of hormonal response on skeletal muscle growth



    To investigate the influence of carbohydrate (CHO) consumption on the acute hormonal response, and chronic adaptation to weight lifting exercise, two studies were conducted. Following a four-hour fast, seven young men (21.3 ± 3.5 y) performed (on two occasions) a nine-station weight lifting protocol, completing 3 sets of 10 repetitions at 75% of IRM (series 1). Randomly assigned, one session included the ingestion of a non-caloric placebo, and the other, a 6% CHO solution. For series 2, two groups of young men (21.3±1.5 y) participated in 12 weeks of progressive resistance weight training. Training for one group included the ingestion of a non-caloric placebo, and the other, a 6% CHO solution. In series 1, weight lifting exercise with CHO ingestion significantly (p < 0.05) elevated blood glucose and plasma insulin levels above baseline, as well as that occurring with the placebo. This resulted in a significant blunting of the cortisol response (7% with CHO compared to 99% with placebo). These findings indicate that CHO consumption during weight lifting exercise can modify the acute hormonal response to exercise. With series 2, CHO consumption continued to blunt the cortisol response to exercise during the twelve weeks of training. This is in contrast to significantly elevated cortisol levels observed for the placebo control group. Corresponding with the modified response patterns were differences in muscle growth. Weight training exercise with CHO ingestion resulted in significantly greater gains in both type I (19.1%) and type II (22.5%) muscle fibre area than weight training exercise alone. The difference in the cortisol response accounted for 74% of the variance (r= 0.8579, p= 0.006) of change in type I muscle fibre area, and 52.3% of the variance (r= 0.7231, p= 0.043) of change in type II muscle fibre area. These findings suggest that the modification of the cortisol response associated with CHO ingestion can positively impact the skeletal muscle hypertrophic adaptation to weigh training.

  14. #54
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    Compartmental distribution of amino acids during hemodialysis-induced hypoaminoacidemia



    The intracellular concentrations of essential amino acids (EAA) in muscle are maintained relatively constant under a variety of conditions. However, the effect of a decrease in blood amino acid concentrations on intracellular concentrations is not clear. Similarly, the relation between intracellular and interstitial concentrations has not been determined in this circumstance. Thus the aim of this study was to determine the effect of hypoaminoacidemia on intracellular, interstitial, and plasma concentrations of EAA and the mechanisms responsible for the respective changes. Twelve normal pigs were investigated before and during 120 min of hemodialysis by use of stable-isotope tracer methodology, microdialysis technique, and muscle biopsies. During hemodialysis, there was a decrease in the interstitial fluid concentrations of phenylalanine, leucine, alanine, and lysine that corresponded to their decrease in plasma concentration. Nonetheless, the intracellular concentrations of these amino acids were maintained at the basal levels throughout the entire period due principally to a reduction in the rate of incorporation of amino acids into protein that was approximately equivalent to the decrease in uptake from the plasma. In conclusion, intracellular concentrations of amino acids are regulated to maintain relatively constant values, even when plasma and interstitial concentrations fall as a consequence of hemodialysis.

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    Revisiting this thread... I am unconvinced.

    For one, even the researchers admit:
    <div class='quotetop'>QUOTE </div><div class='quotemain'>Interpreting results yields a crude but sufficient
    starting point for describing amino acid absorption from the gut, in a g/h absorption
    rate, rather than a more accurate g ∙ h-1 ∙ kg-1 measure.</div>

    Secondly, look at the mass of protein that they're using for samples:
    <div class='quotetop'>QUOTE </div><div class='quotemain'>30 g of [15N]-milk protein</div>
    <div class='quotetop'>QUOTE </div><div class='quotemain'>25 g of 13C-, 15N-, and 2H-labeled egg protein</div>
    <div class='quotetop'>QUOTE </div><div class='quotemain'>30 g [316 mmol N) of [15N]- soy protein isolate</div>
    <div class='quotetop'>QUOTE </div><div class='quotemain'>A mixed amino acid solution (MAA) was designed to mimic that of the amino
    acid profile of a 200 g portion of tenderloin pork steak meal (PS), containing 36 g
    of protein</div>
    <div class='quotetop'>QUOTE </div><div class='quotemain'>30 g (336 mmol N) of labeled
    whey protein (13C-WP), or 43 g (479 mmol N) of labeled casein protein</div>

    I honestly don't think such doses are likely to elicit a maximal response of the intestinal amino acid transporters and digestive machinery. Further, it seems stupendously likely to me (esp from an evolutionary perspective) that these mechanisms would upregulate over time -- both acutely and chronically -- to take advantage of a large-protein meal and a high-protein diet, respectively. The fact that these studies were done on a single day, with a single dose (expect in the multiple whey spikes test) means that this can't test for this possibility.


    Further, many of these studies are using enteral feeding methods... which is great, expect that it's totally artificial. I remember reading in one of McDougal's articles that the act of mastication could recruit pancreatic enzymes. There are a variety of amino acid, di-, and tri-peptide transporters in the bowel, and use of the amino acid mixture (in the pork study, which estimated the highest absorption) can relatively slow gastric emptying as aminos compete for transporters while the di-and tri-peptide transporters remain unutilized.


    Not that this is very good evidence of adaptation, but I'll keep looking.
    <div class='quotetop'>QUOTE </div><div class='quotemain'>J Formos Med Assoc. 1992 Jul;91(7):659-64.Links
    Effects of excess protein intake on nitrogen utilization in young men.

    Huang PC, Chiang A.
    Department of Biochemistry, College of Medicine, National Taiwan University, Taipei, R.O.C.
    The efficiency of nitrogen (N) utilization was studied in 12 young male subjects. Protein intake levels were adjusted from moderate (1.08 and 1.18 g protein/kg/day) to high (1.74 and 2.00 g protein/kg/day). All of the food was supplied in the form of a normal mixed Chinese diet. Six subjects were admitted to a metabolic unit at a time for 56 days, in two consecutive periods. The results indicate that a higher protein intake causes more N excretion in urine and feces. Biologic value (BV) and net protein utilization (NPU) were markedly decreased during the high protein intake (HPI) period. However, a significant increase in the N balance was found in the presence of excessive protein intake. Digestibility of protein seemed to increase during the HPI period, with the apparent digestibility of the dietary protein being about 83% to 90%. We conclude from this study that excessive N intake reduces the efficiency of N utilization, but still results in a positive N balance in adult human subjects.
    PMID: 1360290 [PubMed - indexed for MEDLINE]</div>


    B -- what do you suppose happens with extra protein consumed beyond the hypothetical limit of 10g / hr? Excretion -> N-consuming bacterial fermentation -> protein farts?

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    <div class='quotetop'>QUOTE (dashforce @ Apr 16 2009, 11:55 PM) <{POST_SNAPBACK}></div><div class='quotemain'>B -- what do you suppose happens with extra protein consumed beyond the hypothetical limit of 10g / hr? Excretion -> N-consuming bacterial fermentation -> protein farts?</div>

    Little of both perhaps?

    I wonder if we can find any consumption data for groups like the Masai or Innuit who habitually get the vast bulk of their caloric intake from protein and fat. If anyone was going to have upregulated amino transporters, it would probably be them.

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    <div class='quotetop'>QUOTE (Benson @ Apr 17 2009, 07:00 AM) <{POST_SNAPBACK}></div><div class='quotemain'>Little of both perhaps?

    I wonder if we can find any consumption data for groups like the Masai or Innuit who habitually get the vast bulk of their caloric intake from protein and fat. If anyone was going to have upregulated amino transporters, it would probably be them.</div>

    I don't know which Inuit groups you are referencing, but I can assure you that the diet of most Inuit communities I'm familiar with is definitely not a protein/fat diet.

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    <div class='quotetop'>QUOTE (Ras @ Apr 17 2009, 08:25 AM) <{POST_SNAPBACK}></div><div class='quotemain'>I don't know which Inuit groups you are referencing, but I can assure you that the diet of most Inuit communities I'm familiar with is definitely not a protein/fat diet.</div>

    Traditional diet...maybe its too late. I note that some of the recent studies on the Maasai show that they have adopted a lot of corn into their diet...

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    Personally, I feel better and am leaner on 200g/day protein rather than 400g/day.
    $5 off at iherb.com referral code: REV730

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    does this study take into consideration the subjects doing heavy weight lifting or not?
    id think that would make a differance.

    i.e. we should be able to adapt to handle more than 10g/hour if the need arrises no?
    Currently remixing this old body!

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