Glutamine = Worthless

[Audiowaves252]

I've read about so many people here using glutamine and wondered why? read on...


Effect of glutamine supplementation combined with resistance training in young adults.

Candow DG, Chilibeck PD, Burke DG, Davison KS, Smith-Palmer T.

College of Kinesiology, University of Saskatchewan, Saskatoon, Canada.

The purpose of this study was to assess the effect of oral glutamine supplementation combined with resistance training in young adults. A group of 31 subjects, aged 18-24 years, were randomly allocated to groups (double blind) to receive either glutamine (0.9 g x kg lean tissue mass(-1) x day(-1); n = 17) or a placebo (0.9 g maltodextrin x kg lean tissue mass(-1) x day(-1); n = 14 during 6 weeks of total body resistance training. Exercises were performed for four to five sets of 6-12 repetitions at intensities ranging from 60% to 90% 1 repetition maximum (1 RM). Before and after training, measurements were taken of 1 RM squat and bench press strength, peak knee extension torque (using an isokinetic dynamometer), lean tissue mass (dual energy X-ray absorptiometry) and muscle protein degradation (urinary 3-methylhistidine by high performance liquid chromatography). Repeated measures ANOVA showed that strength, torque, lean tissue mass and 3-methylhistidine increased with training (P < 0.05), with no significant difference between groups. Both groups increased their 1 RM squat by approximately 30% and 1 RM bench press by approximately 14%. The glutamine group showed increases of 6% for knee extension torque, 2% for lean tissue mass and 41% for urinary levels of 3-methylhistidine. The placebo group increased knee extension torque by 5%, lean tissue mass by 1.7% and 3-methylhistidine by 56%. We conclude that glutamine supplementation during resistance training has no significant effect on muscle performance, body composition or muscle protein degradation in young healthy adults.

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J Strength Cond Res 2002 Feb;16(1):157-60
The effects of high-dose glutamine ingestion on weightlifting performance

Antonio J, Sanders MS, Kalman D, Woodgate D, Street C.

Sports Science Laboratory, University of Delaware, Newark, Delaware 19716, USA.

The purpose of this study was to determine if high-dose glutamine ingestion affected weightlifting performance. In a double-blind, placebo-controlled, crossover study, 6 resistance-trained men (mean +/- SE: age, 21.5 +/- 0.3 years; weight, 76.5 +/- 2.8 kg(-1)) performed weightlifting exercises after the ingestion of glutamine or glycine (0.3 g x kg(-1)) mixed with calorie-free fruit juice or placebo (calorie-free fruit juice only). Each subject underwent each of the 3 treatments in a randomized order. One hour after ingestion, subjects performed 4 total sets of exercise to momentary muscular failure (2 sets of leg presses at 200% of body weight, 2 sets of bench presses at 100% of body weight). There were no differences in the average number of maximal repetitions performed in the leg press or bench press exercises among the 3 groups. These data indicate that the short-term ingestion of glutamine does not enhance weightlifting performance in resistance-trained men.




Int J Sports Med 2000 Jan;21(1):25-30 Related Articles, Links


The effect of free glutamine and peptide ingestion on the rate of muscle glycogen resynthesis in man.

van Hall G, Saris WH, van de Schoor PA, Wagenmakers AJ.

Department of Human Biology, Maastricht University, The Netherlands. RH01769@RH.DK

The present study investigated previous claims that ingestion of glutamine and of protein-carbohydrate mixtures may increase the rate of glycogen resynthesis following intense exercise. Eight trained subjects were studied during 3 h of recovery while consuming one of four drinks in random order. Drinks were ingested in three 500 ml boluses, immediately after exercise and then after 1 and 2 h of recovery. Each bolus of the control drink contained 0.8 g x kg(-1) body weight of glucose. The other drinks contained the same amount of glucose and 0.3 g x kg(-1) body weight of 1) glutamine, 2) a wheat hydrolysate (26% glutamine) and 3) a whey hydrolysate (6.6% glutamine). Plasma glutamine, decreased by approximately 20% during recovery with ingestion of the control drink, no changes with ingestion of the protein hydrolysates drinks, and a 2-fold increase with ingestion of the free glutamine drinks. The rate of glycogen resynthesis was not significantly different in the four tests: 28 +/- 5, 26 +/- 6, 33 +/- 4, and 34 +/- 3 mmol glucosyl units x kg(-1) dry weight muscle x h(-1) for the control, glutamine, wheat- and whey hydrolysate ingestion, respectively. It is concluded that ingestion of a glutamine/carbohydrate mixture does not increase the rate of glycogen resynthesis in muscle. Glycogen resynthesis rates were higher, although not statistically significant, after ingestion of the drink containing the wheat (21 +/- 8%) and whey protein hydrolysate (20 +/- 6%) compared to ingestion of the control and free glutamine drinks, implying that further research is needed on the potential protein effect.




Metabolism 2000 Dec;49(12):1555-60 Related Articles, Links


Intravenous glutamine does not stimulate mixed muscle protein synthesis in healthy young men and women.

Zachwieja JJ, Witt TL, Yarasheski KE.

Exercise and Nutrition Program, Pennington Biomedical Research Center, Baton Rouge, LA, USA.

We investigated the effects of a glutamine-supplemented amino acid mixture on vastus lateralis muscle protein synthesis rate in healthy young men and women. Three men and 3 women (27.8 +/- 2.0 yr, 22.2 +/- 1.0 body mass index [BMI], 56.1 +/- 4.5 kg lean body mass [LBM]) received a 14-hour primed, constant intravenous infusion of L[1-13C]leucine to evaluate the fractional rate of mixed muscle protein synthesis. In addition to tracer administration, a clinically relevant amino acid mixture supplemented with either glutamine or glycine in amounts isonitrogenous to glutamine, was infused. Amino acid mixtures were infused on separate occasions in random order at a rate of 0.04 g/kg/h (glutamine at approximately 0.01 g/kg/h) with at least 2 weeks between treatment. For 2 days before and on the day of an infusion, dietary intake was controlled so that each subject received 1.5 g protein/kg/d. Compared with our previous report in the postabsorptive state, amino acid infusion increased the fractional rate of mixed muscle protein synthesis by 48% (P < .05); however, the addition of glutamine to the amino acid mixture did not further elevate muscle protein synthesis rate (ie, 0.071% +/- 0.008%/h for amino acids + glutamine v 0.060% +/- 0.008%/h for amino acids + glycine; P = .316). Plasma glutamine concentrations were higher (P < .05) during the glutamine-supplemented infusion, but free intramuscular glutamine levels were not increased (P = .363). Both plasma and free intramuscular glycine levels were increased when extra glycine was included in the infused amino acid mixture (both P < .0001). We conclude that intravenous infusion of amino acids increases the fractional rate of mixed muscle protein synthesis, but addition of glutamine to the amino acid mixture does not further stimulate muscle protein synthesis rate in healthy young men and women.


J Appl Physiol 2002 Sep;93(3):813-22 Related Articles, Links


Exercise-induced immunodepression- plasma glutamine is not the link.

His**** N, Pedersen BK.

Copenhagen Muscle Research Centre and Department of Infectious Diseases, Rigshospitalet, University of Copenhagen, DK-2100 Copenhagen, Denmark.

The amino acid glutamine is known to be important for the function of some immune cells in vitro. It has been proposed that the decrease in plasma glutamine concentration in relation to catabolic conditions, including prolonged, exhaustive exercise, results in a lack of glutamine for these cells and may be responsible for the transient immunodepression commonly observed after acute, exhaustive exercise. It has been unclear, however, whether the magnitude of the observed decrease in plasma glutamine concentration would be great enough to compromise the function of immune cells. In fact, intracellular glutamine concentration may not be compromised when plasma levels are decreased postexercise. In addition, a number of recent intervention studies with glutamine feeding demonstrate that, although the plasma concentration of glutamine is kept constant during and after acute, strenuous exercise, glutamine supplementation does not abolish the postexercise decrease in in vitro cellular immunity, including low lymphocyte number, impaired lymphocyte proliferation, impaired natural killer and lymphokine-activated killer cell activity, as well as low production rate and concentration of salivary IgA. It is concluded that, although the glutamine hypothesis may explain immunodepression related to other stressful conditions such as trauma and burn, plasma glutamine concentration is not likely to play a mechanistic role in exercise-induced immunodepression.


Effect of glutamine and protein supplementation on exercise-induced decreases in salivary IgA.

Krzywkowski K, Petersen EW, Ostrowski K, Link-Amster H, Boza J, Halkjaer-Kristensen J, Pedersen BK.

The Copenhagen Muscle Research Centre, Rigshospitalet, 2200 Copenhagen, Denmark.

Postexercise immune impairment has been linked to exercise-induced decrease in plasma glutamine concentration. This study examined the possibility of abolishing the exercise-induced decrease in salivary IgA through glutamine supplementation during and after intense exercise. Eleven athletes performed cycle ergometer exercise for 2 h at 75% of maximal oxygen uptake on 3 separate days. Glutamine (a total of 17.5 g), protein (a total of 68.5 g/6.2 g protein-bound glutamine), and placebo supplements were given during and up to 2 h after exercise. Unstimulated, timed saliva samples were obtained before exercise and 20 min, 140 min, 4 h, and 22 h postexercise. The exercise protocol induced a decrease in salivary IgA (IgA concentration, IgA output, and IgA relative to total protein). The plasma concentration of glutamine was decreased by 15% 2 h postexercise in the placebo group, whereas this decline was abolished by both glutamine and protein supplements.None of the supplements, however, was able to abolish the decline in salivary IgA. This study does not support that postexercise decrease in salivary IgA is related to plasma glutamine concentrations.

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Effect of carb intake on plasma glutamine

Int J Sport Nutr 1998 Mar;8(1):49-59 Related Articles, Links


Effect of low- and high-carbohydrate diets on the plasma glutamine and circulating leukocyte responses to exercise.

Gleeson M, Blannin AK, Walsh NP, Bishop NC, Clark AM.

School of Sport and Exercise Sciences, University of Birmingham, Edgbaston, England.

We examined the effects of a low-carbohydrate (CHO) diet on the plasma glutamine and circulating leukocyte responses to prolonged strenuous exercise. Twelve untrained male subjects cycled for 60 min at 70% of maximal oxygen uptake on two separate occasions, 3 days apart. All subjects performed the first exercise task after a normal diet; they completed the second exercise task after 3 days on either a high-CHO diet (75 +/- 8% CHO, n = 6) or a low-CHO diet (7 +/- 4% CHO, n = 6). The low-CHO diet was associated with a larger rise in plasma cortisol during exercise, a greater fall in the plasma glutamine concentration during recovery, and a larger neutrophilia during the postexercise period. Exercise on the high-CHO diet did not affect levels of plasma glutamine and circulating leukocytes. We conclude that CHO availability can influence the plasma glutamine and circulating leukocyte responses during recovery from intense prolonged exercise.

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Clin Nutr 2002 Oct;21(5):423-9 Related Articles, Links


Carbohydrate supplementation during intense exercise and the immune response of cyclists.

Bacurau RF, Bassit RA, Sawada L, Navarro F, Martins E Jr, Costa Rosa LF.

Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Brazil.

OBJECTIVE: To evaluate the effect of carbohydrate supplementation upon some aspects of the immune function in athletes during intense indoor cycling. METHODS: Twelve male athletes cycled for 20 min at a velocity corresponding to 90% of that obtained at the anaerobic threshold and rested for 20 min. This protocol was repeated six times. The athletes received, during the trial, water ad libitum, or a solution of carbohydrate (95% glucose polymers and 5% fructose) at 10% (w/v), 1 g kg h every 20 min, starting at the 10th minute of the first exercise period, plus extra water ad libitum. RESULTS: Exercise induced a reduction in peripheral blood mononuclear cell proliferation (37%) as well as in the production of cytokines by cultured cells (interleukin-1 (IL-1), interleukin-2 (IL-2), tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma), by 37%, 35%, 26% and 16%, respectively). All of these changes were prevented by the ingestion of a carbohydrate drink by the athletes, except that in IFN-gamma production, which was equally decreased (17%) after the second trial. The concentration of plasma glutamine, an important fuel for immune cells, was decreased in the placebo group but maintained in the group that received carbohydrate. CONCLUSION: Carbohydrate supplementation affects positively the immune response of cyclists by avoiding or minimizing changes in plasma glutamine concentration


An excerpt from "Appetite For Construction
Building Results From Research"
by John M. Berardi

Should I Spend my Hard-Earned Money on Glutamine or Hookers?

.... A high protein diet provides a big whack of glutamine as it is. In fact, if you follow standard bodybuilding protein recommendations, about 10% of your total dietary protein intake is composed of glutamine (milk proteins are composed of somewhere between 3 — 10% glutamine while meat is composed of about 15% glutamine). This means that a high protein diet (400g/day) already provides me with about 40g of glutamine.

• While the theorists still cling to the idea that since glutamine helps clinical stress, it might help with exercise stress, it‚s important to note that exercise stress has got nothin‚ on surgery, cancer, sepsis, burns, etc. For example, when compared with downhill running or weight lifting, urinary nitrogen loss is 15x (1400%) greater in minor surgery, 25x (2400%) greater in major surgery, and 33x (3200%) greater in sepsis. When it comes to the immune response, it‚s about 9x (800%) greater with surgery. When it comes to metabolic increase, it‚s 7x (600%) greater with burn injury, and when it comes to creatine kinase release; it‚s about 2x (100%) greater with surgery. As I said, exercise has got nothin‚ on real, clinical stress. It‚s like trying to compare the damage inflicted by a peashooter and that inflicted by a rocket launcher.

• The major studies examining glutamine supplementation in otherwise healthy weightlifters have shown no effect. In the study by Candow et al (2001), 0.9g of supplemental glutamine/kg/day had no impact on muscle performance, body composition, and protein degradation. Folks, that's 90g per day for some lifters.

• The majority of the studies using glutamine supplementation in endurance athletes have shown little to no measurable benefit on performance or immune function.

• And with respect to glycogen replenishment in endurance athletes, it's interesting to note that the first study that looked at glycogen resynthesis using glutamine missed a couple of things. Basically, the study showed that after a few glycogen depleting hours of cycling at a high percentage of VO2 max interspersed with very intense cycle sprints that were supramaximal, a drink containing 8g of glutamine replenished glycogen to the same extent as a drink containing 61g of carbohydrate.

The problem was that during the recovery period, a constant IV infusion of labeled glucose was given (i.e., a little bit of glucose was given to both groups by IV infusion). While this isn't too big of a deal on its own since the infusion only provided a couple of grams of glucose, the other problem is that during glycogen depleting exercise, a lot of alanine, lactate, and other gluconeogenic precursors are released from the muscle.

What this means is that there's a good amount of glucose that will be formed after such exercise, glucose that will be made in the liver from the gluconeogenic precursors and that will travel to the muscle to replenish glycogen. Therefore, without a placebo group that receives no calories, carbohydrates, or glutamine, we have no idea of knowing whether or not the placebo would have generated the same amount of glycogen replenishment as the glutamine group or the glutamine plus carbohydrate group. To say it another way, perhaps there's a normal glycogen replenishment curve that was unaffected by any of the treatments.

• And finally, with respect to the claims that glutamine might increase cell swelling/volume (something I once believed was a reality), we decided to test this theory out in our lab using multifrequency bioelectric impedance analysis as well as magnetic resonance spectroscopy. The pilot data that's kicking around has demonstrated that glutamine supplementation has no effect on total body water, intracellular fluid volumes, or extracellular fluid volumes (as measured by mBIA) and has no effect on muscle volume (as measured by nMRS)...


and I have a ton more if you would like me to post them

[ste]

This should be interesting...

[BboySoul]

wow.. thats one persepctive.

[Fireproof]

deleted.

[Audiowaves252]

Interesting,

well read this, and hopefully soon you'll be convinced

Glutamine
Destroying the Dogma, Part 1
by David J. Barr


One of the most frequent supplement questions I get as a strength coach is whether or not athletes should use the amino acid glutamine for either performance enhancement or size gains.

The topic comes up so much that it almost seems as though glutamine is a "no brainer" supplement just like creatine. In fact, its popularity is such that at least two separate online message boards, as well as numerous magazines, have feature articles on the use of glutamine as a supplement. The dogma of glutamine supplementation had even permeated the SWIS symposium to the extent that the numerous conversations about this amino acid were solely about how much to take, rather than whether or not to take it.

So, it seems as though everything is pretty cut and dried when it comes to glutamine use… or is it? While there was some literature-supported speculation as to the potential benefits of glutamine supplementation, there needs to be an updated review of the literature examining the current status of this purported "wonder supplement." In fact, there's quite a bit of information that's been left out of the popular bodybuilding literature that needs to be brought to light.

But before we get on to that, we should review some of the basics of glutamine.


Glutamine: The Basics

For those of you who are new to the concept of glutamine supplementation, you should know that it's a non-essential amino acid created largely by our muscles. It's also noteworthy that glutamine is the most abundant free amino acid in our bodies, comprising up to 2/3 of the muscle free amino acid pool.(13) This fact, coupled with the idea that muscle is the largest producer of this amino acid, could suggest that supplementation would be beneficial.

One potential problem with this is that glutamine is a non-essential amino acid (meaning that we don't have to consume outside sources containing this amino acid because our bodies can make it on its own), but this is where things get interesting: the use of glutamine by many different cells in our bodies is so great that there may be times when its use exceeds its availability, therefore glutamine has been termed a "conditionally essential" amino acid.(18)

This means that during times of physical stress the body may actually need glutamine from the diet to maintain proper cellular function. Clearly, activities such as resistance training constitute a physical stress on the body, which is one reason that athletes have been targeted for glutamine supplementation.

Another interesting fact about our muscles and glutamine is the issue of transport. For an amino acid to get into or out of our muscles, it has to be transported by specific carriers. Using these carriers, our muscle takes up amino acids according to demand from protein composition (i.e. what our muscles need the most), BUT amino acid release is NOT according to composition.

Alanine and glutamine can account for up to 50% of amino acid release from muscle despite accounting for only about 15% of total muscle protein.(31) Obviously, this is a huge discrepancy—which is normally made up for through glutamine production—but as mentioned earlier, during times of physical stress (i.e. exercise), the synthesis of glutamine is hindered. Everyone knows that lacking even one amino acid can hinder muscle growth, which fortifies the theory of glutamine supplementation by athletes.

Now that you're familiar with the basics behind glutamine supplementation, it's time to delve into the literature and pull out some more specific theories as to the beneficial effects of glutamine supplementation.


Glutamine and Muscle Mass

Interest first arose in glutamine as a supplement when it was found that glutamine enrichment elevated levels of protein synthesis in isolated rat muscles.(21) This isn't surprising since it's also been found that muscle protein synthesis levels can be correlated with free glutamine levels.(17) It's also been shown in vitro using rat skeletal muscle cells that glutamine may decrease protein breakdown.(22)

Additionally, we know that the anabolic/catabolic state of a muscle cell is related to it's hydration status—this simply means that cellular swelling has an anabolic or an anticatabolic effect on the affected cells (including muscle cells). Based on this, it's been found that glutamine supplementation may mediate cell swelling and therefore an anticatabolic effect through either increasing cell swelling or hindering cellular dehydration.(28)

Sure you say, these theories are all well and good in cell cultures or animals, but what about the human studies? Well, studies in humans indicate that glutamine supplementation may improve nitrogen balance in critically ill patients, as well as assist in the prevention of protein synthesis decreases following surgery (a HUGE physical stress) or following a 14-hour fast.(13, 12,24,13) There have even been a couple of studies done on resistance trained subjects (more on that a little later)!


Glutamine and Overtraining

We've all felt the scourge of overtraining: the lethargy, the sickness, and the lack of desire to train. Aside from the horrible feeling associated with overtraining, we also know that the longer we're out of the gym, the longer we go without any anabolic stimulus to our muscles. Based on this, another theory suggesting glutamine supplementation for athletes involves the prevention of overtraining.

Glutamine is used as a fuel source by many cells of our body, including many cells of our immune system. Now if you recall that there are times of stress where the body's production fails to meet its needs for glutamine, you can see that this could negatively affect the immune system. In fact, you may not be surprised to find that blood glutamine levels may be compromised following exercise induced overtraining.(1)

Surveys of endurance athletes supplementing with glutamine following a marathon race showed lower rates of infection than those who didn't supplement.(8,9) As for the applicability to bodybuilding, one study showed that resistance exercise may induce a small transient (ie short-term) negative effect on some cells of the immune system, although plasma glutamine levels weren't examined.(6)

So now we have theories for glutamine supplementation to increase protein synthesis/inhibit protein breakdown, as well as boost immunity following intense exercise. This sounds great, but we have yet to look at glutamine's potential effect to stimulate glycogen replenishment following exercise. Glutamine infusion has been shown to enhance glycogen stores following cycling exercise twice as much as compared to subjects who infused saline or other amino acids.(27) If this happened after weight training, it could even help with our cellular swelling and have the aforementioned postive effect on protein accretion.

Another study supports the use of glutamine for enhancing muscle glycogen. Bowtell et al. found that glutamine supplementation following exercise enhanced glycogen resynthesis in muscle just as well as the ingestion of a glucose polymer.(4)

Sadly at this point, many readers have already gone out and bought their kilos of glutamine, and are now reading only to find out how to use the stuff. You may argue, why not? There's plenty of evidence to support the theories presented! This was exactly the thinking when glutamine was introduced to bodybuilders several years ago. In fact, the journal articles reviewed above are the same research papers that can be found time and again, in any outdated article that's trying to sell you on glutamine. But things have recently changed; new studies have been done on animals, and people involved in resistance training, but the results are less than positive.


What the Glutamine Salespeople Don't Want You To Know:

Glutamine and Protein Synthesis — The other side of the coin

We've seen the theory that glutamine levels in the blood and muscle may decrease during or following exercise, and that this decrease correlates with reduced levels of protein synthesis. Several studies have addressed whether this relationship between glutamine and protein synthesis was a coincidental or a causal (meaning that one caused the other) relationship.

The first study compared the abilities of glutamine and the amino acid alanine to stimulate protein synthesis in rats with artificially reduced blood and muscle glutamine levels.(23) As expected, glutamine infusion increased intramuscular glutamine levels, while alanine didn't. Surprisingly, even depleting muscle glutamine levels by 60% had no effect on protein synthesis. What may also surprise you is that restoring blood and muscle glutamine levels to normal had no effect on protein synthesis compared to rats receiving no glutamine treatment! Additionally, even though whole body protein turnover didn't change, alanine stimulated protein synthesis!

In support of this contention, researchers studied the effect of glutamine supplementation on septic rats. Sepsis is a severely catabolic condition, during which glutamine levels (and protein synthesis) fall. Again, this study showed that despite increasing muscle glutamine levels to even higher than normal, it had no effect on protein synthesis or the catabolic state of the rats.(11)

Cumulatively, these studies show that decreased or increased levels of glutamine in the muscle has no effect on protein synthesis.

Another study, performed on people, examined the effect of adding glutamine to an amino acid mixture on muscle protein synthesis .(30) Ultimately, infusion of the original amino acid mixture increased protein synthesis by nearly 50%, but adding glutamine to this mix had no additional effect. This study is particularly relevant because most consumers of glutamine do so following a workout, along with other amino acids (or a whole protein).

Finally, Wusteman et al., used a drug to reduce muscle protein synthesis, along with muscle glutamine levels, in rats.(29) Much like the Olde Damink et al. study, restoring muscle glutamine levels to normal had no effect on protein synthesis. This study further supports the concept that blood and muscle glutamine levels have no bearing on protein synthesis and protein turnover.


Editor's note: Part 2, which pretty much presents a case for relegating glutamine to the Retired Supplements shelf (except for very specific circumstances) will be posted next week.


David J. Barr, CSCS, MSc. Candidate, is a Varsity Strength and Conditioning Coach at the University of Waterloo

[Audiowaves252]

heres part 2 for you... ****, look at all those references

Last week, David Barr started shooting holes into the reputation of the long-standing bodybuilding supplement, glutamine.. While glutamine was staggered and bleeding at the end of part 1, watch as Barr sticks a sharp knife into glutamine's still barely beating heart and twists it.


Another One Bites the Dust

You may recall that the theory of exercise induced immunosuppression is often cited, based on the fact that glutamine levels decrease after exercise, as does our immunity.(10)

What we must now address is whether the relationship between the body’s glutamine stores and the effects of exercise on the immune system exhibit a causal or coincidental relationship (just as we did for protein synthesis). A recent review article in "The Journal of Applied Physiology" examined this connection between plasma glutamine and exercise-induced immunosuppression.(15)

The study admitted that there are conflicting reports about plasma glutamine levels following long duration exercise, repeated high intensity bouts, as well as short single high intensity bouts. This indicates that plasma glutamine concentrations may be affected differently depending on the intensity and duration of exercise.

Even data on blood glutamine concentrations following eccentric exercise is mixed, which can relate directly to bodybuilders and their use of heavy loads. Based on the relatively small reductions in plasma glutamine that might occur following exercise, supplementation with glutamine wouldn’t likely affect the immune cells.

More importantly, there are several studies showing that glutamine supplementation doesn't alter exercise-induced suppression of the immune system! The bottom line is that blood glutamine levels, whether they drop or not following exercise, don’t seem to affect immunity to any great extent, which precludes the use of glutamine for this reason.

Another recent review looked at over 75 research papers pertaining to the effect of glutamine on immunity and muscle growth, and came to the following conclusion: "Overall, although glutamine obviously plays important metabolic roles within the body, supplementation does not appear to provide consistent beneficial or therapeutic effects, except during certain catabolic situations. Glutamine availability, therefore, does not seem to be a limitation in many challenge situations."(19)


What about the glycogen?!

Yep, we have one final theory to validate spending God-awful amounts of money on glutamine; that of enhanced glycogen resynthesis following our workouts. In addition to the aforementioned studies showing better glycogen storage, there is also a study showing no effect of oral glutamine on glycogen regeneration following high intensity interval training.(26)

This issue was actually addressed by the authors of the Candow study, who found no strength or mass changes in trained individuals using glutamine (versus a placebo).(7) They suggested that the studies done showing enhanced glycogen recovery used exercise bouts which depleted intramuscular glycogen by 90%(!), while resistance exercise only depletes muscular glycogen by ~36%.

The bottom line is that the jury is still out on glutamine enhancing glycogen resynthesis following resistance exercise, but it seems unlikely that it would have any effect. Toss in the huge amounts of high glycemic carbs that most of us use following our workouts, and it’s almost a sure bet that glutamine won’t do anything for additional glycogen storage under normal dietary situations.


Things That Mom Never Told You About Glutamine Supplementation

It’s important to examine the method used for getting glutamine into the body in the human studies presented. Unfortunately, getting glutamine into our blood and to our muscles is a lot harder than one may expect. It was mentioned earlier that many cells of the body use glutamine for fuel. Well one area of cells that just loves glutamine is the gastrointestinal tract. In fact, it can account for up to 40% of glutamine utilization in the body! Now figure out the first area to come into contact with our "wonder supplement," and you can see that you have to take a whole crap-load of the stuff all at once, just so our gut doesn’t use it all!

Now, dumping 20g of one amino acid into our bodies at once may sound fun to some, but then again we can safely call these people masochists. For the rest of us, this huge glutamine dump may lead to some GI distress, which we all know is NOT fun.

Fortunately, the two studies performed with bodybuilders using relatively high dosages of glutamine (0.3g/kg/d and 0.9g/kg lean mass/d) reported no side effects of any kind.(2, 7) What is unfortunate is that the authors of these studies also showed no positive effect of any kind!


Glutamine and Resistance Trained Athletes: The Studies

One recent study examined the effect of acute glutamine ingestion on weightlifting performance.(2) This study examined the potential buffering effect of glutamine on lactic acid production during resistance exercise (to the point of momentary muscular failure).

One hour following glutamine ingestion (0.3g/kg), glycine ingestion (0.3g/kg), or placebo drink ingestion, the trained subjects performed 2 sets each of leg press (@ 200% body weight) and bench press (@ 100% body weight). This would equate to an average of ~23g of either amino acid ingested all at once, but there were no reports of GI discomfort.

Each subject consumed one of the three supplements before three separate testing sessions separated by a week. There was no effect of glutamine on number of reps performed compared to glycine or placebo ingestion. These results indicate that a high dose of glutamine ingested before exercise has no positive or negative effects on weightlifting performance in trained subjects.

If you’re interested in glutamine for its effect on muscle mass and strength, you’re in luck because a study was done on that, too! This next study is undoubtedly one of the best kept secrets in bodybuilding! In this study, the trained subjects consumed either 0.9g/kg lean body mass/day (average of 45g/day!), or a placebo, in 2 divided doses.(7)

It's noteworthy that using this amount of glutamine would run over 1200$USD per year for a 200lb guy!

By the end of the 6-week period, there were no differences in terms of 1Rep Max on squat or bench between the groups. There were also no differences between groups when it came to the gains in lean body mass (i.e. the amount of muscle they put on) during the trial period. This study was well designed and used the highest amount of glutamine ever studied for these purposes.


Glutamine Ain't All That Bad

After kicking the crap out of glutamine for most bodybuilding purposes, it is important to realize that there are certain situations where glutamine can be useful.

A recent study from the journal "Metabolism" shows that glutamine injections following glucocorticoid (ie catabolic steroid -such as cortisol) treatment can increase protein synthesis in the gastrointestinal system of dogs.(16) Unfortunately, nonoxidative leucine disposal, a measure of whole-body protein synthesis, remained unchanged in the glutamine treated group.

There are a dozen ways you could interpret these findings, but at least we can say that glutamine supplementation may improve protein synthesis in some tissues following gluccocorticoid treatment. In fact, glucocorticoid treatment is one area where glutamine supplementation may really help!

Another study with rats supports this contention, again using corticosteroid administration.(14) Although glutamine infusion had no effect on muscle protein synthesis in the rats not receiving cortisol, there was a beneficial effect in the glucocorticoid treated rats. In fact, glutamine infusion actually attenuated more than 70% of the muscle wasting caused by the cortisol injections!

Along these lines, certain catabolic conditions (such as sepsis) may be another useful situation in which glutamine could help out. One literature review clearly concluded that "The increased intake of glutamine has resulted in lower septic morbidity in certain critically ill patient populations."(3) This means that people with certain catabolic medical conditions may live longer when taking glutamine. Keeping this in mind, we also know that AIDS can be associated with muscle wasting. Recent evidence has arisen to demonstrate that glutamine supplementation may attenuate AIDS-induced muscle wasting.(25)

Overall, these studies show that glutamine could be very helpful for muscle mass during corticosteroid treatment and certain wasting conditions. For those of you who think that your everyday training may be intense enough to simulate a catabolic condition, keep in mind that these people are dying because of their catabolism, so you're really no where near that level.

The only time a bodybuilder even remotely approaches these kind of catabolic conditions is when improperly coming off a cycle of anabolic steroids. In this situation the user has minimal anabolic stimulus from Testosterone and a large amount of cortisol just waiting to eat that muscle (again, this is only when done improperly). In this situation, glutamine supplementation might help, but it's not a situation you should be in anyway.

The other time that glutamine supplementation may be beneficial to bodybuilders is when on a low carbohydrate diet. Glutamine can not only be converted to glucose, but may also have an anapleurotic effect.(5) In other words, it may replenish metabolic intermediates, in this case, ATP (especially important when you're lacking carbs). This is another article unto itself, so I'll leave it at that for now.

You may be asking why you’ve never heard of most of these studies, and why everything you’ve heard about glutamine was always so amazing. I can indirectly answer that by reminding you of one simple fact: no one makes money by showing that supplements don’t work. I’ll leave the rest of the thinking on this matter to you.

Despite this, you may still be skeptical regarding the points mentioned, based on the original dogmatic theories associated with glutamine use (and how long you’ve been hit over the head with them). But then again, that’s why they’re just theories. To paraphrase Homer Simpson: "Sure it may work in theory, but then again even communism works...in theory."

It's the mark of a great person who can devise a theory, drawing from many different ideas, and stick to it. Without this, science would be meaningless. But it's the mark of an even greater person when they can admit, without shame, that their idea is wrong.

Sometimes theories pan out and sometimes they don’t, but we have to be able to let go of them once they're shown to be incorrect. This doesn’t mean that we shouldn’t believe new theories when they first come out; it just means that we have to be conscious about the fact that they aren’t dogma and may be wrong.

Case in point: The theory behind glutamine was so great that I refused to believe the authors of the Candow et al. (2001) study when they told me the results in person. I was an educated bodybuilder and I wasn’t going to let some egghead scientist (who was actually more muscular than I was, and therefore far from being just an "egghead") tell me that I was wrong. Of course, I wanted to believe that glutamine was useful (even though I got nothing from it) and when someone wants to believe something you can’t convince them otherwise.

Since then I’ve had a while to let the results sink in. I know that most believers in glutamine will also have a hard time accepting the reality of the situation, which is why I didn’t just try to convincingly show that glutamine wasn’t as great as everyone thought; I tried to overwhelmingly demonstrate it.


Bottom Line

Glutamine is good for hospital patients and rich people with money to waste. If you’re involved in resistance training and already have proper post workout nutrition, along with a moderate carb intake, then glutamine probably won’t do anything for you. In fact, none of the proposed theories dealing with glutamine supplementation have worked out in the athletic world. It’s also one of the most expensive supplements around (simply based on dosage recommendations), so it’s way too costly to use for personal experimentation — especially when the updated scientific literature doesn’t support the theories.


David J. Barr, CSCS, MSc. Candidate, is a Varsity Strength and Conditioning Coach at the University of Waterloo. You can contact him at dbmuscle@hotmail.com.


References

1. Antonio J, Street C.

Glutamine: a potentially useful supplement for athletes. Can J Appl Physiol 1999 Feb;24(1):1-14

2. Antonio J, Sanders MS, Kalman D, Woodgate D, Street C.

The effects of high-dose glutamine ingestion on weightlifting performance. J Strength Cond Res 2002 Feb;16(1):157-60

3. Boelens PG, Nijveldt RJ, Houdijk AP, Meijer S, van Leeuwen PA.

Glutamine alimentation in catabolic state. J Nutr 2001 Sep;131(9 Suppl):2569S-77S; discussion 2590S

4. Bowtell JL, Gelly K, Jackman ML, Patel A, Simeoni M, Rennie MJ.

Effect of oral glutamine on whole body carbohydrate storage during recovery from exhaustive exercise. J Appl Physiol 1999 Jun;86(6):1770-7

5. Bruce M, Constantin-Teodosiu D, Greenhaff PL, Boobis LH, Williams C, Bowtell JL.

Glutamine supplementation promotes anaplerosis but not oxidative energy delivery in human skeletal muscle. Am J Physiol Endocrinol Metab 2001 Apr;280(4):E669-75

6. Bush JA, Dohi K, Mastro AM, Volek J, Lynch JM, Triplett-McBride, Putukian M, Sebastianelli WJ, Newton RU, Hakkinen K, Kraemer WJ. Exercise and recovery responses of lymphokines to heavy resistance exercise J Str Cond Res 2000 14(3) 344-349

7. Candow DG, Chilibeck PD, Burke DG, Davison KS, Smith-Palmer T.

Effect of glutamine supplementation combined with resistance training in young adults. Eur J Appl Physiol 2001 Dec;86(2):142-9

8. Castell LM, Poortmans JR, Newsholme EA.

Does glutamine have a role in reducing infections in athletes? Eur J Appl Physiol Occup Physiol 1996;73(5):488-90

9. Castell LM, Newsholme EA.

The effects of oral glutamine supplementation on athletes after prolonged, exhaustive exercise. Nutrition 1997 Jul-Aug;13(7-8):738-42

10. Castell LM.

Can glutamine modify the apparent immunodepression observed after prolonged, exhaustive exercise? Nutrition 2002 May;18(5):371-5

11. Fang CH, James JH, Fischer JE, Hasselgren PO.

Is muscle protein turnover regulated by intracellular glutamine during sepsis? JPEN J Parenter Enteral Nutr 1995 Jul-Aug;19(4):279-85

12. Hammarqvist F, Wernerman J, von der Decken A, Vinnars E.

Alanyl-glutamine counteracts the depletion of free glutamine and the postoperative decline in protein synthesis in skeletal muscle. Ann Surg 1990 Nov;212(5):637-44

13. Hankard RG, Haymond MW, Darmaun D.

Effect of glutamine on leucine metabolism in humans. Am J Physiol 1996 Oct;271(4 Pt 1):E748-54

14. Hickson RC, Czerwinski SM, Wegrzyn LE.

Glutamine prevents downregulation of myosin heavy chain synthesis and muscle atrophy from glucocorticoids. Am J Physiol 1995 Apr;268(4 Pt 1):E730-4

15. His**** N, Pedersen BK.

Exercise-induced immunodepression- plasma glutamine is not the link. J Appl Physiol 2002 Sep;93(3):813-22

16. Humbert B, Nguyen P, Dumon H, Deschamps JY, Darmaun D.

Does enteral glutamine modulate whole-body leucine kinetics in hypercatabolic dogs in a fed state? Metabolism 2002 May;51(5):628-35

17. Jepson MM, Bates PC, Broadbent P, Pell JM, Millward DJ.

Relationship between glutamine concentration and protein synthesis in rat skeletal muscle. Am J Physiol 1988 Aug;255(2 Pt 1):E166-72

18. Lacey JM, Wilmore DW.

Is glutamine a conditionally essential amino acid? Nutr Rev 1990 Aug;48(8):297-309

19. Lobley GE, Hoskin SO, McNeil CJ.

Glutamine in animal science and production. J Nutr 2001 Sep;131(9 Suppl):2525S-31S; discussion 2532S-4S

20. Low SY, Taylor PM, Rennie MJ.

Responses of glutamine transport in cultured rat skeletal muscle to osmotically induced changes in cell volume. J Physiol 1996 May 1;492 ( Pt 3):877-85

21. MacLennan PA, Brown RA, Rennie MJ.

A positive relationship between protein synthetic rate and intracellular glutamine concentration in perfused rat skeletal muscle. FEBS Lett 1987 May 4;215(1):187-91

22. MacLennan PA, Smith K, Weryk B, Watt PW, Rennie MJ.

Inhibition of protein breakdown by glutamine in perfused rat skeletal muscle. FEBS Lett 1988 Sep 12;237(1-2):133-6

23. Olde Damink SW, de Blaauw I, Deutz NE, Soeters PB.

Effects in vivo of decreased plasma and intracellular muscle glutamine concentration on whole-body and hindquarter protein kinetics in rats. Clin Sci (Lond) 1999 Jun;96(6):639-46

24. Petersson B, von der Decken A, Vinnars E, Wernerman J.

Long-term effects of postoperative total parenteral nutrition supplemented with glycylglutamine on subjective fatigue and muscle protein synthesis. Br J Surg 1994 Oct;81(10):1520-3

25. Shabert JK, Winslow C, Lacey JM, Wilmore DW.

Glutamine-antioxidant supplementation increases body cell mass in AIDS patients with weight loss: a randomized, double-blind controlled trial. Nutrition 1999 Nov-Dec;15(11-12):860-4

26. van Hall G, Saris WH, van de Schoor PA, Wagenmakers AJ.

The effect of free glutamine and peptide ingestion on the rate of muscle glycogen resynthesis in man. Int J Sports Med 2000 Jan;21(1):25-30

27. Varnier M, Leese GP, Thompson J, Rennie MJ.

Stimulatory effect of glutamine on glycogen accumulation in human skeletal muscle. Am J Physiol 1995 Aug;269(2 Pt 1):E309-15

28. Vom Dahl S, Haussinger D.

Nutritional state and the swelling-induced inhibition of proteolysis in perfused rat liver. J Nutr 1996 Feb;126(2):395-402

29. Wusteman M, Tate H, Elia M.

The use of a constant infusion of [3H]phenylalanine to measure the effects of glutamine infusions on muscle protein synthesis in rats given turpentine. Nutrition 1995 Jan-Feb;11(1):27-31

30. Zachwieja JJ, Witt TL, Yarasheski KE.

Intravenous glutamine does not stimulate mixed muscle protein synthesis in healthy young men and women. Metabolism 2000 Dec;49(12):1555-60

31. Zorzano A, Fandos C, Palacin M.

Role of plasma membrane transporters in muscle metabolism. Biochem J 2000 Aug 1;349 Pt 3:667-88

[realjones]

do you know of any studies regarding glutamine supplementation with regards to "cutting" diets? Like if the glutamine actually helped to retain muscle mass or not?

[MansonOzz]

I used free form L-Glutamine while on my cut and I sure lost some muscle mass. Next time I'm not going to waste my money.

[William Ustav]

I think Joe will bring up a tons of other studies that proves otherwise. Let's see... /forum/images/graemlins/wink.gif

[Adam Knowlden]

[ QUOTE ]
I've read about so many people here using glutamine and wondered why?

[/ QUOTE ]

Because of something you read from an advertiser's magazine?

First you are showing abstracts. The entire study needs to be researched, not just abstracts to call a supplement "worthless". THis is due to the variables, constants, and controls, that can alter the desried studies effect.

All of the studies you quoted reveal more research needs done to prove it's anabolic effects, not that the supplement is worthless. IMO, the author of those articles jumped to very big conclusions from the research. Also you only showed inconclusive journal entires, there are hundreds of journal entries that reveal the anabolic effects of glutaime.

Notice that here in Antonio's '99 journal entry.

Strength and Conditioning Journal: Vol. 21, No. 6, pp. 17–17.

NUTRITION NOTES: Glutamine
Jose Antonio, CSCS

University of Nebraska–Kearney

[ QUOTE ]
FOR THE MILLIONS WHO REGULARLY ingest dietary supplements, you're probably left wondering if these items actually help your body or just hurt your wallet (or purse). Besides creatine, protein, and a few others, much of what's sold over the counter has little hard-core scientific backing. With that caveat, the ever-growing popularity of glutamine as a supplement to enhance the immune system and prevent the loss of muscle mass needs further examination.

[/ QUOTE ]

[ QUOTE ]
Future research should examine the potential utility of glutamine supplementation on aerobic and anaerobic athletes.


[/ QUOTE ]

[ QUOTE ]
So is glutamine a “conditionally essential” amino acid for athletes? The jury is still out on this one.


[/ QUOTE ]

1. Antonio, J., and C. Street. Glutamine: A potentially useful supplement for athletes. Can. J. Appl. Physiol. 24:(1)1–14. 1999.

2. Castell, L.M., J.R. Poortmans, and E.A. Newsholme. Does glutamine have a role in reducing infections in athletes?. Eur. J. Appl. Physiol. 73:488–490. 1996.

I see nothing calling glutamine worthless, only that not much hardcore scientific research has been done on it. This was in 1999!

[ QUOTE ]
These data indicate that the short-term ingestion of glutamine does not enhance weightlifting performance in resistance-trained men.


[/ QUOTE ]

Short term being the key word here, which Candow whom you quoted later stated this is a big reason why major effects of glutamine did not show up, along with other variables.

Your article takes his study totally out of context, to "prove" glutaimine is "worthless", which is not at all the conclusion reached by the scientists whom did the research. Essentially, he put words in their mouth. We'll see that study in a bit.

But let's first look at the whole Antonio study you quoted, not just the abstract.

[ QUOTE ]

The Journal of Strength and Conditioning Research: Vol. 16, No. 1, pp. 157–160.

The Effects of High-Dose Glutamine Ingestion on Weightlifting Performance
JOSE ANTONIO, MICHAEL S. SANDERS, DEREK WOODGATE, and CHRIS STREET



ABSTRACT

The purpose of this study was to determine if high-dose glutamine ingestion affected weightlifting performance. In a double-blind, placebo-controlled, crossover study, 6 resistance-trained men (mean ± SE: age, 21.5 ± 0.3 years; weight, 76.5 ± 2.8 kg1) performed weightlifting exercises after the ingestion of glutamine or glycine (0.3 g·kg1) mixed with calorie-free fruit juice or placebo (calorie-free fruit juice only). Each subject underwent each of the 3 treatments in a randomized order. One hour after ingestion, subjects performed 4 total sets of exercise to momentary muscular failure (2 sets of leg presses at 200% of body weight, 2 sets of bench presses at 100% of body weight). There were no differences in the average number of maximal repetitions performed in the leg press or bench press exercises among the 3 groups. These data indicate that the short-term ingestion of glutamine does not enhance weightlifting performance in resistance-trained men.

Reference Data:Antonio, J., M.S. Sanders, D. Kalman, D. Woodgate, and C. Street. The effects of high-dose glutamine ingestion on weightlifting performance.


Key Words: amino acid, supplement, nutrition, protein.

Introduction Return to TOC

Glutamine is the most abundant amino acid in plasma and skeletal muscle (5) and accounts for greater than 60% of the total intramuscular free amino acid pool (8). During metabolic acidosis, glutamine is converted to -ketoglutarate, thus generating ammonium ions (NH4+). The excretion of ammonium ions helps buffer metabolic acidosis. This is of relevance to athletes who engage in intense anaerobic exercise in that fast glycolysis is accompanied by a significant increase in plasma lactate and hydrogen ion concentration. This decrease in pH may reduce the ability to perform further high-intensity exercise (1, 9).

Previous work has demonstrated that increasing the plasma pH via sodium bicarbonate or sodium citrate ingestion can improve anaerobic exercise performance (2, 7). If the short-term ingestion of glutamine exerts a beneficial effect on anaerobic work output, it could prove useful to strength athletes and athletes involved in high-intensity anaerobic training. The purpose of this investigation was to study the effects of short-term, high-dose glutamine ingestion on strength in resistance-trained men.

Welbourne (10) demonstrated that the oral ingestion of 2 g of glutamine increased plasma bicarbonate concentrations in normal, healthy subjects. High-intensity exercise that uses the lactic acid energy system brings about dramatic alterations in acid-base status. It is known that by increasing the pH of extracellular fluid and blood, an improvement of exercise performance can be achieved (2, 7). Therefore, we speculated that the ingestion of high doses of glutamine (averaging 23 g) could have an ergogenic effect based on its ability to increase extracellular pH. Glutamine given orally at 0.3 g·kg1 was selected because of previous work by Ziegler and colleagues (11), who showed this amount to be free of toxicity in humans.

The current investigation did not find any benefit to ingesting glutamine 1 hour before strength testing. We surmise this lack of benefit was due to negligible actions of short-term glutamine supplementation on muscle metabolism. Dosages we administered were 10 times greater than those used by Haub et al (3), which is the only other published investigation to study the effects of short-term glutamine ingestion on exercise performance. Haub et al gave 0.03 g·kg1, and 90 minutes after ingestion, subjects performed 4 bouts of 60-second cycling at 100% O2 peak followed by a fifth bout to exhaustion. There was no difference in performance in the fifth bout of cycling to exhaustion between the glutamine and placebo groups. Our study used a much higher dose of glutamine and a different mode of exercise, yet no ergogenic benefit was shown. We did not measure plasma bicarbonate to determine if glutamine ingestion increased plasma pH nor did we ascertain plasma lactate concentrations to confirm the anaerobic nature of the exercise bout. Despite this flaw, the lack of response to glutamine seen in our laboratory suggests negative results were not due to inadequate dosing, but to glutamine's lack of immediate activity in skeletal muscle. Future investigations should build on our work and assess the manner in which glutamine supplementation might improve anaerobic performance.

The huge variability in leg press performance seen in these subjects would suggest a short-term neural adaptation. Although subjects trained regularly with weights, they did not regularly perform repetitions to momentary muscular failure for the leg press exercise. There was less variation observed in bench press exercise performance. This was due to the fact that subjects performed the bench press regularly in their own training and were cognizant of the exertion necessary for a maximal bench press effort.

Another aspect to the study that we attempted to control for was the possibility that the mere provision of additional amino nitrogen might have an ergogenic effect, hence our rationale for glycine administration. Data presented herein suggest glycine had no effect on strength performance and appear to rule out amino nitrogen as a performance factor. In conclusion, glutamine does not have ergogenic properties when taken orally (0.3 g·kg1) 1 hour before resistance exercises.



Practical Applications Return to TOC

Short-term glutamine ingestion has no effect on muscular strength; however, long-term supplementation may be a more feasible application of glutamine (5, 6, 8). Glutamine might exert positive effects on performance due to a concatenation of physiological events, such as serving as a gluconeogenic precursor and fuel source for cells of the immune system and gastrointestinal tract, modulating cellular volume, and an anticatabolic effect on skeletal muscle.From the medical literature, glutamine may have a place in the dietary regimen of athletes undergoing intense exercise training and possibly have a role in maintaining optimal health during the competitive season via benefits to the immune system. The current study demonstrated, however, that this amino acid has no immediate effects on weightlifting performance. Future work should examine long-term supplementation of glutamine in athletes during a competitive season.

References Return to TOC

1. Chasiotis, D., E. Hultman, and K. Sahlin. Acidotic depression of cyclic AMP accumulation and phosphorylase b to a transformation in skeletal muscle of man. . J. Physiol. 335:197–204. 1983. [PubMed Citation]

2. Costill, D., F. Verstappen, H. Kuipers, E. Jansson, and W. Fink. Acid-base balance during repeated bouts of exercise: influence of bicarbonate. Int. J. Sports. 5:228–231. 1984.

3. Haub, M.D., J. A. Potteiger, K.L. Nau, M.J. Webster, and C.J. Zebas. Acute L-glutamine ingestion does not improve maximal effort exercise. J. Sports Med. Phys. Fitness. 38:240–244. 1998. [PubMed Citation]

4. Jackson, A.S., and M.L. Pollock. Generalized equations for predicting body density of men. Br. J. Nutr. 40:497–504. 1978. [PubMed Citation]

5. Lacey, J.M., and D.W. Wilmore. Is glutamine a conditionally essential amino acid?. Nutr. Rev. 48:297–309. 1990. [PubMed Citation]

6. Perriello, G., N. Nurjhan, and M. Stumvoll. et al. Regulation of gluconeogenesis by glutamine in normal post-absorptive humans. Am. J. Physiol. 272:E437–E445. 1997.

7. Potteiger, J., G. Nickel, M. Webster, M. Haub, and R. Palmer. Sodium citrate ingestion enhances 30 km cycling time. Int. J. Sports Med. 17:7–11. 1996. [PubMed Citation]

8. Rowbottom, D.G., D. Keast, and A.R. Morton. The emerging role of glutamine as an indicator of exercise stress and overtraining. Sports Med. 21:80–97. 1996. [PubMed Citation]

9. Sutton, J., N. Jones, and C. Toews. Effect of pH on the kinetics of frog muscle phosphofructokinase. J. Biol. Chem. 241:4110–4112. 1966. [PubMed Citation]

10. Welbourne, T. Increased plasma bicarbonate and growth hormone after an oral glutamine load. Am. J. Clin. Nutr. 61:1058–1061. 1995. [PubMed Citation]

11. Ziegler, T.R., K. Benfell, R.J. Smith, L.S. Young, E. Brown, E. Ferrari- Baliviera, D.K. Lowe, and D.W. Wilmore. Safety and metabolic effects of L-glutamine administration in humans. J. Parenter. Enteral. Nutr. 14:137–146S. 1990.



[/ QUOTE ]

The next study is a 2003 journal so using the excuse "outdated" will not work here.

Also Candow's study and his critique is mentioned here. That is why you have to look at the whole study, not just the abstract. The studies reveal that often times the variables and constants may not be correct for the intended results as Candow theorizes in the study you posted here:

"Effect of glutamine supplementation combined with resistance training in young adults.
Candow DG, Chilibeck PD, Burke DG, Davison KS, Smith-Palmer T."


[ QUOTE ]


"The effects of 8 weeks of creatine monohydrate and glutamine supplementation on body composition and performance measures."


ABSTRACT

Twenty-nine (17 men, 12 women) collegiate track and field athletes were randomly divided into a creatine monohydrate (CM, n = 10) group, creatine monohydrate and glutamine (CG, n = 10) group, or placebo (P, n = 9) group. The CM group received 0.3 g creatine;pdkg body mass per day for 1 week, followed by 0.03 g creatine;pdkg body mass per day for 7 weeks. The CG group received the same creatine dosage scheme as the CM group plus 4 g glutamine;pdday1. All 3 treatment groups participated in an identical periodized strength and conditioning program during preseason training. Body composition, vertical jump, and cycle performances were tested before (T1) and after (T2) the 8-week supplementation period. Body mass and lean body mass (LBM) increased at a greater rate for the CM and CG groups, compared with the P treatment. Additionally, the CM and CG groups exhibited significantly greater improvement in initial rate of power production, compared with the placebo treatment. These results suggest CM and CG significantly increase body mass, LBM, and initial rate of power production during multiple cycle ergometer bouts.

Nutritional supplements have for some time been suggested to enhance athletic performance. However, the vast majority of research studies do not support the ergogenic potential of many nutritional supplements. Glutamine and creatine monohydrate supplementation may be 2 supplements that have substantial ergogenic potential. The ergogenic potential of creatine supplementation has received considerable attention in the scientific literature, but substantially less attention has been directed at glutamine supplementation and its ergogenic effects.

Glutamine supplementation has become increasingly popular in athletic populations (9) as a result of scientific evidence that suggests that ingestion of exogenous glutamine by humans can improve glycogen resynthesis (8, 60) and immune responses (10–12, 46, 49–51) following endurance exercise. The majority of these data support the ingestion of 4- to 5-g doses of pure glutamine (10). Additionally, scientific evidence suggests that glutamine supplementation may have an effect on skeletal muscle protein levels (58).

Glutamine appears to exert a large effect on muscle protein catabolism and protein synthesis in animal (42, 43) and human models (24). MacLennan et al. (42) have demonstrated that glutamine significantly increases intracellular concentrations of glutamine and protein synthesis in rat models. Additionally, MacLennan et al. (43) have demonstrated that glutamine has an antiproteolytic effect on the noncontractile protein content of rat skeletal muscle. In humans, Hankard et al. (24) report that the infusion of glutamine increases protein synthesis. Increases in muscle protein synthesis or prevention of protein catabolism occur following physiological stress, such as surgery in humans, when glutamine supplementation is employed (23). Vom Dahl and Haussinger (64) suggest that glutamine may exert these anticatabolic effects on muscle protein by mediating increases in cellular volume.

Glutamine may promote increases in cellular volume and osmolarity as a result of an insulin dependent sodium dependent transport system (1, 2, 26, 34). Haussinger and Lang (25) and Haussinger et al. (27) suggest that increased cellular swelling is an anabolic proliferative signal, which may translate into an increase in muscle mass over time. Antonio and Street (2) suggest that the ergogenic effects of glutamine supplementation may be important for athletes in strength power sports, such as track and field. The protein sparing and synthesis effects of glutamine supplementation may potentially result in improved markers of sports performance (power production, vertical jump performance, or overall muscular strength) as a direct result of increases in muscle mass.

Candow et al. (9) demonstrated that the ingestion of 0.9 g;pdkg1 glutamine during 6 weeks of strength training in a mixed population of active individuals (21 men and 19 women) did not result in significantly greater increases in muscular strength and lean body mass, compared with a placebo treatment. Candow et al. (9) suggested that their findings may have resulted from the short duration of training (6 weeks) and that a longer training period may result in the occurrence of ergogenic effects with glutamine supplementation.Additionally, Candow et al. (9) suggested that the large glutamine dosage used in their investigation may have potentiated the lack of ergogenic effects as a result of an inhibitory effect and that it is possible that a smaller supplementation dosage could stimulate positive ergogenic effects. Finally, Candow et al. (9) suggested that the training stimulus may not have resulted in enough stress and that protocols that employ combinations of training stimuli may produce a larger stressor for the athlete and should be study in conjunction with glutamine supplementation. On the basis of these findings, it is possible that a smaller dosage of glutamine coupled with a longer training program that incorporates more training stimulus could result in increases in lean body mass that may ultimately result in improvements in sports performance.

Similar to glutamine, it has been suggested that increases in lean body mass (16, 35, 38, 39, 47, 55, 61, 62) occur with creatine supplementation, especially when coupled with a structured resistance training program (35, 55). Volek and Kraemer (62) suggested that the increase in lean body mass associated with creatine supplementation results from an increase in cellular swelling as the direct result of a sodium dependent transport mechanism. This cellular swelling mechanism has been suggested to be an anabolic signal that over time results in increases in lean body mass (25, 27). Ziegenfuss et al. (66) have shown that short-term (&lt;5 days) creatine supplementation results in a 2% increase in total body water, 3% increase in intracellular fluid volume, and no effect on extracellular fluid volume. These results suggest that short-term creatine supplementation results in increases in body mass as a result of elevations in fluid retention. Over the long term, it has been suggested that creatine supplementation results in an elevation in body mass and lean body mass as a result of increases in protein synthesis (19, 62). Francaux and Poortmans (19) reported that after 21 days of creatine supplementation that body mass is significantly increased. These increases appear to be partially related to increases in absolute body water content and absolute intracellular compartment water volume. There was no increase seen in the relative body water and intracellular compartment volumes, which led the researchers to conclude that the body mass gains seen following the supplementation protocol were a direct result of protein synthesis. On the basis of the current scientific literature, creatine supplementation appears to result in greater increases in body mass and lean body mass when utilized in conjunction with a resistance training program (16, 63). These increases in body mass and lean body mass may ultimately result increases in overall strength, power, and ability to complete repetitive anaerobic exercise bouts.

Currently the popular literature recommends the combination of creatine and glutamine in supplements as a way to increase muscle mass and muscular strength (17). It is often suggested the popular literature that these two supplements act as cell volumizers to enhance the synthesis of muscle mass. Based on the scientific literature, it is hypothetically possible that the combination of creatine and glutamine supplements could result in an increased cellular swelling that could enhance the anabolic signal (25, 27) and result in increased muscle mass and possibly improved performance in strength power athletes. However, the present authors know of no studies that have investigated these hypotheses in athletes. Therefore, the major purpose of this investigation is to elucidate the effects of combining creatine and glutamine supplementation on body mass, lean body mass, and markers of anaerobic performance in track and field athletes who are undergoing a preseason strength and conditioning program. It is our hypothesis that the combination a preseason resistance training program with a glutamine and creatine supplementation regimen would enhance body mass, lean body mass, vertical jump performance, vertical jump power, and multiple bout cycle ergometer performance.

Experimental Approach to the Problem

A randomized, double-blind research design was utilized in an attempt to assess the effects of creatine monohydrate (CM) supplementation and creatine monohydrate + glutamine (CG) supplementation on body mass, body composition, dynamic explosive strength, and repeated anaerobic cycle ergometer performance. Track and field athletes were selected for the present study based on previous research that suggests that creatine supplementation can significantly alter body mass, explosive strength, and repeated anaerobic performance when coupled with a resistance training protocol in this population (35). All subjects participated in an 8-week preseason strength and conditioning program coupled with supplementation with CM, CG, or a placebo. Supplementation was divided into a 1-week loading phase and a 7-week maintenance phase. Testing was conducted prior to and immediately after the 8 weeks of supplementation.
Subjects

Twenty-nine male (n = 17) and female (n = 12) collegiate track and field athletes (sprinters, jumpers, and throwers) participated in this 8-week supplementation study. A mixed-subject population was selected based on previously published data, which show that men and women both respond to creatine supplementation without gender specific responses (45, 59). Additionally, support for a mixed population design can be found in a recent study looking at creatine supplementation and a mixed population of track athletes undergoing a preseason conditioning program that demonstrated significant ergogenic effects that were manifested as both body mass and performance increases (35). All male subjects were members of the 2001 Southern Conference Indoor Championship Runner-Up Team and the Outdoor Championship Team. All female subjects were members of the 2001 Southern Conference Indoor Championships Team and the Outdoor Championship Runner-Up Team.
All subjects signed informed consent in keeping with American College of Sports Medicine and university guidelines. All subjects agreed to abstain from using any other supplementation (except multivitamins and minerals) during the 7 weeks prior to the investigation. Additionally, none of the subjects included in the investigation was a vegetarian or an anabolic drug user. After the initial testing session, the subjects were randomly assigned to one of three groups. Groups received one of the following treatments: creatine monohydrate (group CM: n = 10, age 19.4 ± 0.3 years, height 175.8 ± 2.5 cm, weight 70.7 ± 3.2 kg); creatine monohydrate and glutamine (group CG: n = 10, age 19.2 ± 0.3 years; height 175.3 ± 2.7 cm; weight 73.5 ± 4.5 kg), or a placebo (potato starch) (group P: n = 9, age 20.1 ± 0.6 years, height 175.0 ± 3.1 cm, weight 72.0 ± 2.7 kg). The three groups were not significantly different based on body mass, height, age, and event. Additionally, there were no statistical differences between the treatment groups for the number of female athletes in each grouping.

Supplementation

The 8-week supplementation period was divided into two phases. The first phase or loading phase required the subjects in the CG group to consume 0.3 g creatine per kilogram body mass per day plus 4 g of glutamine per day for 1 week. The CM group consumed 0.3 g creatine per kilogram body mass per day plus 4 g placebo per day for 1 week. The P group consumed 0.3 g placebo per kg body mass plus an additional 4 g of placebo per day. The second phase (maintenance phase) required the subjects in the CG group to consume 0.03 g creatine per kilogram body mass per day plus 4 g of glutamine for 7 weeks. The CM group also consumed 0.03 g creatine per kilogram body mass per day plus 4 g placebo per day for 7 weeks. The P group consumed 0.03 g placebo per kg body mass plus an additional 4 g of placebo per day for 7 weeks. The creatine supplementation scheme used in the present study is based on the work of Hultman et al. (30). Hultman et al. (30) found that a loading dosage of 0.3 g creatine per kilogram body mass per day for 6 days can significantly elevate muscular stores of creatine. Additionally, it has been reported that after a 6-day loading period, 0.03 g creatine per kilogram body mass per day can maintain muscular stores of creatine at the level achieved in loading (30). The dosage of 4 g;pdd1 glutamine was selected based on the current 4–5 g per day recommendation in the literature exploring glutamine supplementation in low intensity exercise endurance populations (10–12, 46, 49–51).
During the loading phase, subjects were required to report to the Human Performance Laboratory 3 times a day: between 0700 and 1000 hours, at 1500 hours (before practice), and at 1700 hours (immediately after practice) and were observed taking the supplement (22, 35). During the maintenance phase of the study, subjects reported to the laboratory at 1500 hours to receive their supplement. The 4 g of glutamine or placebo was always taken at 1500 hours in both the loading and maintenance phases All supplements were administered in a double-blind fashion and supplied in capsule form to prevent the subjects and researchers from introducing bias into the investigation. Plastic bags containing the supplements were labeled with a subject identification number and supplied to the subjects when they received their treatment (22, 35). On weekends, the subjects were supplied with enough supplements to meet their required dosages. Subjects were required to return the bags with a supplement form, which had their signature, a witness's signature, and the time each dosage was taken (22, 35). Information supplied by Twinlab Inc. (Hauppauge, NY) indicated that the creatine and the glutamine were greater than 90% pure determined by high pressure liquid chromatography methods.

Training Sessions

An 8-week preseason sports specific resistance training program was used to train all of the subjects participating in the present investigation (Table 1 ). The duration of preseason training program was chosen based on previous literature, which has demonstrated significant ergogenic effects when creatine supplementation is utilized during 8 weeks of sport-specific training in elite collegiate athletes (56). There were no differences in the training programs among the three groups. All training sessions were monitored by the research team and track team strength and conditioning coach. Each subject completed a training log, which was collected at the end of each training week. Data from the training logs were analyzed for volume load. Volume load was calculated for each exercise by multiplying repetitions by weight lifted in kilograms (54). Training volume was measured because several authors have suggested that increases in training volume are the main stimuli for the ergogenic effects induced by creatine supplementation (35, 57).
Diet

Three-day diet records (2 weekdays and 1 weekend day) coupled with an interview with our staff dietitian were used during the second, fourth, and sixth weeks of the study. Prior to each data collection, our dietitian discussed portion sizes and diet record techniques with each of the subjects. Three-day diet records were chosen because diet records that last longer than 5 to 6 days appear to cause subjects to alter their eating habits in an attempt to streamline the record-keeping process (41). Data were analyzed by a registered dietitian for total calories and macronutrient content (carbohydrate, protein, and fat) using the Food Processor Plus for Windows, version 6.05 (ESHA Research, Salem, OR) (44). The Food Processor for Plus for Windows was selected based on a recent study, which gave the software package high ratings and reported a low percentage (0.3%) of missing information (40).
Testing Sessions

The subjects were tested on 2 occasions. All tests were performed before the 8-week supplementation period (T1) and at the end (T2) of the study. All variables were measured at T1 and T2.
Subjects reported to the Human Performance Laboratory following an overnight fast and were assessed for body mass, height, and body composition. Body mass was measured to the nearest 0.1 kg on a model 400 Healthometer physician's scale (Continental Scale Corp., Bridgeview IL), and body height was measured to the nearest 0.1 cm with a stadiometer. Body composition (lean body mass and percent fat) was assessed using 2 different methods: a hydrostatic weighing technique and a 7-site skinfold measurement (31, 52). At least 6 underwater weights were measured on each occasion. Three consecutive measures that agreed were used in the data analysis. Residual volume (measured in the same body position by the same tester) was conducted using a multibreath open-circuit nitrogen washout procedure (Cosmed Pulmonary Function Equipment, Rome, Italy). Skinfolds were measured by the same investigator at T1 and T2 and performed using Lange skinfold calipers (Cambridge Scientific Industries, Cambridge, MD). Percent fat was determined using the Siri equation (52). Test-retest reliability for skinfold measures of body composition was R = 0.99, and the reliability of the hydrostatic weighing procedures was found to be R = 0.98.

Static and countermovement vertical jumps were measured with the Vertec (Sports Performance, Columbus, OH) and used to evaluate dynamic explosive strength. Previous research from our laboratory suggests that both static and countermovement vertical jump measures are enhanced with creatine supplementation and serve as an effective measure of dynamic explosive strength (22, 35, 55). All vertical jump methodologies were based on these previous studies.

One week prior to each testing session, all subjects were required to perform a familiarization test consisting of 2 static and 2 countermovement vertical jumps. All subjects were required to perform a standardized warm-up consisting of 1-minute side straddle hops and 2 minutes of light stretching (35). Subjects were then given the opportunity for 1 practice jump. Reach height was then determined with the subjects' feet flat on the ground and arms maximally extended over their heads (35). The last bar of the Vertec, which they could move with their fingertips, was recorded as the reach height. Each subject performed 3 countermovement vertical jumps. During each jump test, the subjects were given a countdown from 3 to 1 and were then instructed to jump on the command “jump” (35). A 1-minute rest was given between each of the jump trials. The depth of knee flexion and arm movements (countermovement) performed by each subject was self-determined. The best value of the three respective jumps was then used for analysis. Following the 3 countermovement vertical jumps, subjects were instructed on proper static vertical jump technique. Briefly, subjects were required to lower to a point at which their upper leg was parallel with the ground. This position was held until the countdown was completed and the jump command was given (35). Three static vertical jumps were performed and the best jump was then used for analysis. The vertical jump displacement was determined by subtracting the reach height from the best jump height achieved during the countermovement and static vertical jump trials. The calculated vertical jump height was then used to determine a power measure (35, 55). The power measure was determined for both the static and countermovement vertical jump with the Lewis formula (55) and Johnson peak and average power equations (32). Vertical jumps were measured T1 and T2 by the same group of testers. Test-retest reliability for the static vertical jump displacement was determined to be R = 0.96, and the test-retest reliability of the countermovement vertical jump displacement was determined to be R = 0.97.

Measurement of power and work was assessed by the use of 5 × 5-second maximum cycle ergometer rides. The present cycle ergometer test was selected based on previous research that suggests that high-intensity repetitive short-duration cycle ergometer bouts are enhanced with creatine supplementation (5, 15, 33, 37). All rides were performed on a Monark cycle ergometer model 868 (Monark-Cresent AB, Barberg, Sweden). Previous research from our laboratory suggests that multiple cycle ergometer rides. One week prior to each testing session all subjects performed a familiarization trial consisting of two 5-second rides. Subjects were required to warm up for 1 minute while pedaling against no resistance (35). The resistance on the ergometer was then set at 0.1 kg;pdkg body mass1. Subject's feet were then taped into the pedals. Once the subject was securely fastened to the ergometer a 2-second burst of pedaling was performed to become familiar with the resistance of the ergometer (35). The Monark cycle ergometer was interfaced with an Apple IIgs (Apple, Cupertino, CA) microcomputer equipped with a Nalandata A2A data acquisition unit and was fitted with electromagnetic switches. The computer was fitted with specifically designed software (Nalan Computer Specialties, Boone, NC) to calculate work and power data (35). Power and work samples were determined each half-pedal revolution with a sample resolution of 4 milliseconds (55). A 50-second recovery period was given between each cycle ride. Values determined by use of the ergometer software included peak power, average peak power, peak power per body mass, average peak power per body mass, average power, and total work. A test-retest reliability of R = 0.98 was determined for both peak and average power on the cycle ergometer. Total and average work on the cycle ergometer was found to have a test-retest reliability of R = 0.97. Additionally, the test-retest reliability of the initial rate of power production was determined to be R = 0.96.

Statistical Analyses

Data were analyzed with a repeated-measures group × trials analysis of variance, with an alpha level of p 0.05. Interactions were tested using paired t-tests and the Holm's sequential Bonferroni method to control for type I errors (29). All values are reported as means ± SEM. Test-retest reliability was assessed with the use of interclass correlations. All statistical analyses were performed with SPSS 10.0 (SPSS, Chicago, IL).

Results Return to TOC

Table 2 depicts the dietary results for the CG, CM, and P treatment groups. Statistical analyses revealed no significant difference between the 2 treatments for kilocalories, carbohydrate, protein, or fat. No significant differences existed within each group from the PRE, MID, and POS measurements.

Body mass and LBM (hydrostatic and skinfolds) increased significantly over time (p &lt; 0.05). A significant interaction showed that both body mass and lean body mass (LBM) (skinfolds) for the CM and CG groups increased more than the P treatment (p &lt; 0.016). However, LBM based on hydrostatic measures did not exhibit a significant interaction. Percent fat and fat mass exhibited no significant changes over time and no interactions (Table 3 ).

The static vertical jump (SVJ) and countermovement vertical jump (CVJ) and tests were used to assess dynamic explosive strength and power. Both CVJ and SVJ displacements increased significantly over time (p &lt; 0.05). However, no significant differences in vertical jump displacement for either CVJ or SVJ existed among the 3 treatment groups. Lewis equation power estimates showed a significant increase over time, but no significant interactions were noted between treatments (Table 4 ).

The peak and average peak cycle power increased significantly from T1 to T2. However, no significant differences existed among the treatment groups. Additionally, when peak and average peak power values were adjusted per kilogram body mass, a significant increase was noted from T1 to T2, with no significance differences among groups. The average power achieved over the 5 rides demonstrated a significant time effect resulting in T2 &gt; T1 and no difference among treatment groups. When average powers were adjusted per kilogram body mass, there was a significant time effect with T2 &gt; T1, with no significant difference existing among treatment groups. A summary of cycle peak and average powers is presented in Table 5 . When examining the peak and average powers generated during the 5 individual rides, there was a significant time effect from T1 to T2 but no significant difference among groups (Figures 1 and 2 ). When looking at the total and average work accomplished over the 5 rides, a significant time effect was noted for all groups, but no significant interactions were noted. Additionally, when looking at total and average work per kilogram body mass, the results for all groups were statistical difference between T1 and T2. No differences existed among treatments (Table 6 ). A significant time effect (p &lt; 0.02) and group-by-time interaction (p &lt; 0.03) was noted for the initial rate data (Figure 3 ), with the CG and CM groups being greater than the P treatment.

When examining the training data, it was determined that no significant differences existed among the CG, CM, and P groups for total volume load and weekly volume load accomplished (Table 7 ).



Discussion Return to TOC

To our knowledge, this is the first study to investigate the effects of combining oral creatine and glutamine supplementation with a preseason strength and conditioning program in an athletic population. We hypothesized that coupling a creatine and glutamine supplementation regime would result in increases in body mass, lean body mass, vertical jump performance, and cycle ergometry performance, compared with a traditional creatine supplementation regimen. However, the results of the present study suggests that the addition of 4 g of glutamine to a creatine supplementation regimen showed minimal effects on body mass, lean body mass, and anaerobic performance, compared with creatine supplementation alone, but both CM and CG treatments resulted in significant increases in LBM, body mass, and initial rate of power production during multiple cycle ergometry bouts, compared with the P treatment. This finding is significant in that glutamine supplementation is very popular among strength power athletes (36) and often suggested to enhance the ergogenic effects of creatine supplementation (17).

In the present study, it was hypothesized that both the CM and CG would result in significantly greater increases in body mass based on consistent findings of a 0.9- to 3.8-kg increase in body mass with creatine supplementation in the scientific literature (3, 4, 13, 16, 19, 20, 35, 38, 39). In the present study, the CM and CG treatments resulted in a significantly greater increase in body mass (CM: +1.7 kg; CG: +2.3 kg) than the P treatment (P: +0.2 kg) over the 8 weeks of supplementation. Generally, the increases in body mass associated with long-term (&gt;8 days) creatine supplementation regimens have been suggested to be a result of increases in protein synthesis (3, 18, 55), which may be manifested as LBM gains. The results of the skinfold data in the present study suggest that both CM and CG supplementation resulted in significant increases in both body mass and LBM when coupled with a strength and conditioning program. These data are in agreement with previously reported research, which suggests that creatine monohydrate increases LBM (22, 55, 63). Based on these findings, CG and CM supplementation regimens have the potential to magnify the body mass and LBM adaptations to a structured strength and conditioning program.

On the basis of the current literature, it was hypothesized that the CG treatment would result in a significantly larger anabolic signal as a result of a larger stimulus by the cellular swelling mechanism (25–27, 64) and result in greater protein synthesis in response to the strength and conditioning program (2). Unexpectedly, the CG treatment group did not experience significantly greater LBM gains, compared with the CM treatment group. However, the CG group experienced a nonstatistically significant absolute body mass increase (CM: +1.7 kg; CG: +2.3 kg) and LBM increase (hydrostatic: CM: +2.4 kg; CG: +2.9 kg; skinfold: CM +2.2 kg; CG: +3 kg), which was greater than that of the CM group. This data might suggest that the addition of 4 g of glutamine to a creatine supplementation regimen is not enough to significantly enhance LBM gains that occur from CM supplementation.

Strength training programs that employ explosive exercises have been shown to result in significant improvements in vertical jump performance (54). Therefore, the significant improvements in both CVJ (CM: +3.8 cm; CG: +3.4 cm; P: +2.5 cm) and SVJ (CM: +2.1 cm; CG: +3.4 cm; P: +1.0 cm) displacements after the 8 weeks of supplementation and training were expected. Several investigations have reported that vertical jump performance can be improved with the combination of a creatine supplementation and a periodized resistance training program (7, 22, 35, 56). However, no difference in the improvement rates of the treatment groups were seen for the SVJ or CVJ performances in the present study, even though all three groups experienced significant gains in jumping performance. Several authors suggest that because vertical jumping tasks takes less than 1 second to complete, it is not likely that the phosphocreatine (PCr) stores are a limiting factor as an energy substrate for this activity (22, 35, 55).

Often the vertical jump performance test is used in an attempt to evaluate power production capabilities (54). Kirksey et al. (35) have reported significant improvements in countermovement vertical jump power outputs in track and field athletes who undertake creatine supplementation protocols in conjunction with a resistance training program. Conversely, Haff et al. (22) have reported that 42 days of creatine supplementation does not alter vertical jump power outputs in track and field athletes. The present study also found no significant differences between the static and countermovement vertical jump power outputs in track and field athletes. However, when looking at the data (Table 4 ) the CG and CM experience nonsignificantly greater gains in CVJ (CM + 8.4%, CG + 7.9%) and SVJ (CM + 6.0%; CG + 7.9%) peak power when compared with the P treatment (CVJ + 4.3%, SVJ + 2.0%). The data of the present study seem to suggest that CM or CG do not favorably alter vertical jump power production capabilities in this population of track athletes.

Repeated anaerobic cycle ergometer tests are another method often used to assess the effects of creatine supplementation on anaerobic power and work capacity because of their ability to stress the phosphagen and glycolytic systems (55). The present study found that 56 days of CM or CG supplementation enhanced the initial rate of power production during 5 × 5-second cycle ergometer performance in track and field athletes. However, there were no significant differences between the CM and CG treatment groups. The results of the present study are similar to those reported by Kirksey et al. (35) for track and field athletes. Kirksey et al (35) reported that 42 days of creatine supplementation results in significant increases in initial rate of power production during 5 sets of 10-second cycle exercise. Additionally, Kirksey et al. (35) demonstrated significant increases in average cycle peak power and cycle average power. However, no differences were seen in the present study among treatment groups for cycle peak power, cycle average power, and total work capacity. The results in the present study are similar to the results reported by Stone et al. (55) for collegiate football players. Because both the present study and the study by Stone et al. (55) used multiple 5-second rides and found no significant increases in cycle ergometer average power production, peak power production, and total work output with creatine, it is possible that the 5 × 5-second test duration was not long enough to significantly stress the phosphagen system.

Hirvonen et al. (28) reported that the PCr concentration is not significantly reduced until the high-intensity effort has been sustained for 5–7 seconds. Because the present cycle ride only lasted 5 seconds, it is likely that only minimal reductions in PCr concentrations were experienced and the recovery time between rides was sufficient enough to restore the ride-induced decrements in PCr. Wootton and Williams (65) have shown that 60 seconds of recovery between multiple cycle rides allows for a maintenance of performance. The present study utilized a 50-second recovery period, and this may partially explain why no differences were seen among the treatment groups. Conversely, Kirksey et al. (35) reported significant increases in cycle performance using 5 × 10-second cycle sprints with 50 seconds of recovery. It is likely that the 10-second ride length explains why Kirksey et al. (35) were able to find significant improvements in cycle performance, but the present study did not.

One limitation to the present study may be the relatively short duration of training (8 weeks). When utilizing trained subjects, it is often difficult to get large alterations in performance over short periods of training (53, 55). However, the present study demonstrates large improvements in vertical jump performance that would suggest that the collegiate athletes tested were not elite. Additionally, the duration of the present study was selected based on several studies, which utilized collegiate athletes (football players and track athletes), lasted 5–8 weeks, and demonstrated that creatine supplementation had significant ergogenic benefits (22, 35, 55, 56). The present study found similar ergogenic benefits as a result of creatine supplementation to those reported in the literature (22, 35, 55, 56).

A second limitation may be the dosage of glutamine selected for use in the present study. Several studies have suggested rather large dosages of glutamine may be need to counteract the fall in muscle protein synthesis and improve nitrogen balance of surgery patients (9, 23, 48). Petersson (48) has suggested that the glutamine dosage may need to be as high as 20 g;pdd1, and Hammarqvist et al. (23) suggest a 0.285 g;pdkg body mass1d1. It is possible that the 4 g dosage selected in the present study was not enough to impact the protein synthesis or protein degradation rates. A larger dosages may be needed when glutamine is consumed orally (9) because approximately 50% of the glutamine absorbed from the gut lumen is metabolized by the gut and lumen (14). However, Candow et al. (9) have found that 45 g·d1 of glutamine supplementation did not enhance muscle protein synthesis and muscular adaptation in response to a resistance training program. Therefore, it is possible that the inclusion of a larger glutamine dosage that ranges between 20–45 g coupled with the creatine supplementation protocol may be needed to magnify the cellular swelling induced anabolic signal for protein synthesis and thus induce greater gains in body mass, LBM, and performance than those reported in the present study.

The mixture of male and female subjects may be an additional limitation of the present study. A mixed-subject population was selected based on previously published data, which show that men and women both respond to creatine supplementation without gender-specific responses (45, 59). Additionally, support for a mixed-population design can be found in 2 recent studies looking at creatine supplementation and a mixed population of track athletes undergoing a preseason conditioning program (22, 35). Both studies demonstrated that creatine can elicit significant ergogenic effects that are manifested as both body mass and performance increases. Based on these studies, the use of a mixed-gender subject population should not significantly alter the ergogenic benefits of either creatine or glutamine.

When looking at the scientific literature it was expected that the CM and CG treatments coupled with a periodized training program would result in significantly greater performance enhancements than those seen in the present study. The lack of difference in performance gains between the treatment groups most likely occurred because of the lack of difference in the volume loads of the treatment groups. Syrotuik et al. (57) have reported that when the training loads and volumes are the same for creatine and placebo treatments, no training advantages occur. This lack of training advantage would then ultimately result in similar alterations in performance among the treatment groups. In the present study, the periodized training programs administered to all the athletes were identical and specified distinct intensities and volumes. After the study it was determined that the total volume load undertaken was not significantly different among the 3 treatment groups. It is very likely that the subjects in the CM and CG treatment groups did not deviate from the prescribed training programs and therefore did not encounter a greater training stimulus. Several authors have suggested that the ergogenic mechanism of creatine is the ability to handle higher training volumes and intensities (35, 57). This phenomenon may partially explain why only marginal performance gains were seen when CM and CG supplementation were undertaken.

The present study seems to suggest that 8 weeks of CM or CG supplementation coupled with an explosive resistance training regimen can lead to positive changes in body composition, body mass, and initial rate of power production during multiple cycle ergometer bouts. At present, the addition of 4 g of glutamine to a CM supplementation protocol does not significantly enhance the benefits of CM supplementation. It is important to note that not all of the mechanisms and ergogenic effects of CM or glutamine are completely understood. More research is required to further understand these mechanisms and effects. Additional research exploring the ergogenic effects and efficacy of glutamine supplementation are needed. Finally, long-term investigations exploring the potential side effects of CM and glutamine supplementation are needed.



Practical Applications Return to TOC

The results of the present study suggest that the CM and CG can have a significant impact on body mass and LBM of track and field athletes who are participating in an 8-week periodized strength training regime. From a practical standpoint, adding 4 g of glutamine to a CM supplementation regimen appears to offer little additional ergogenic effect on body mass or LBM. However, when looking at the trend in the data, it is possible that larger dosages of glutamine may be needed to stimulate the hypothesized increase in body mass and LBM, but this has yet to be substantiated in the scientific literature.

Several investigators have suggested that the main stimulus for improved performance is the ability of creatine to stimulate a situation in which the athlete can train with higher volumes and intensities (35, 57, 63). Based on the present study and data presented by Syrotuik et al. (57), it appears that there is a distinct interaction among training volume, intensity, and the ability of creatine to stimulate improvements in performance. Therefore, athletes who are utilizing CM or CG supplementation in an attempt to improve performance should try to maximize the training stimulus through manipulations of training volume and intensity.



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33. Kamber, M., M. Koster, R. Kreis, G. Walker, C. Boesch, and H. Hoppeler. Creatine supplementation. Part I: Performance, clinical chemistry, and muscle volume. Med. Sci. Sports Exerc. 31:1763–1769. 1999. [PubMed Citation]

34. Keast, D., D. Arstein, W. Harper, R.W. Fry, and A.R. Morton. Depression of plasma glutamine concentration after exercise stress and its possible influence on the immune system. Med. J. Aust. 162:15–18. 1995. [PubMed Citation]

35. Kirksey, B., M.H. Stone, B.J. Warren, R.L. Johnson, M. Stone, G.G. Haff, F.E. Williams, and C. Proulx. The effects of six weeks of creatine monohydrate supplementation on performance measures and body composition in collegiate track and field athletes. J. Strength Cond. Res. 13:148–156. 1999.

36. Kreider, R.B. Dietary supplements and the promotion of muscle growth with resistance exercise. Sports Med. 27:97–110. 1999. [PubMed Citation]

37. Kreider, R.B., M. Ferreira, M. Wilson, and A. Almada. Effect of creatine supplementation with and without glucose on repetitive sprint performance in trained and untrained men and women. Int. J. Sport Nutr. 8:204–205. 1998.

38. Kreider, R.B., M. Ferreira, M. Wilson, P. Grindstaff, S. Plisk, J. Reinardy, E. Cantler, and A.L. Almada. Effects of creatine supplementation on body composition, strength, and sprint performance. Med. Sci. Sports Exerc. 30:73–82. 1998. [PubMed Citation]

39. Kreider, R.B., R. Klesges, K. Harmon, P. Grindstaff, L. Ramsey, D. Bullen, L. Wood, Y. Li, and A. Almada. Effects of ingesting supplements designed to promote lean tissue accretion on body composition during resistance training. Int. J. Sport Nutr. 6:234–246. 1996. [PubMed Citation]

40. Lee, R.D., and D.C. Nieman. Comparison of eight microcomputer dietary analysis programs with the USDA nutrient data base for standard reference. J. Am. Diet. Assoc. 95:858–867. 1995. [PubMed Citation]

41. Lee, R.D., and D.C. Nieman. Nutritional Assessment. St. Louis, MO: Mosby-Year Book, Inc., 1996.

42. MacLennan, P.A., R.A. Brown, and M.J. Rennie. A positive relationship between protein synthetic rate and intracellular glutamine concentration in perfused rat skeletal muscle. FEBS Lett. 215:187–191. 1987. [PubMed Citation]

43. MacLennan, P.A., K. Smith, B. Weryk, P.W. Watt, and M.J. Rennie. Inhibition of protein breakdown by glutamine in perfused rat skeletal muscle. FEBS Lett. 237:133–136. 1988. [PubMed Citation]

44. Nieman, D.C. The food processor for windows. J. Am. Diet. Assoc. 97:1337 1997.

45. Parise, G., S. Mihic, D. MacLennan, K.E. Yarasheski, and M.A. Tarnopolsky. Effects of acute creatine monohydrate supplementation on leucine kinetics and mixed-muscle protein synthesis. J. Appl. Physiol. 91:1041–1047. 2001. [PubMed Citation]

46. Parry-Billings, M., R. Budgett, Y. Koutedakis, E. Blomstrand, S. Brooks, C. Williams, P.C. Calder, S. Pilling, R. Baigrie, and E.A. Newsholme. Plasma amino acid concentrations in the overtraining syndrome: Possible effects on the immune system. Med. Sci. Sports Exerc. 24:1353–1358. 1992. [PubMed Citation]

47. Pearson, D.R., D.G. Hamby, W. Russel, and T. Harris. Long-term effects of creatine monohydrate on strength and power. J. Strength Cond. Res. 13:187–192. 1999.

48. Petersson, B., S.O. Waller, E. Vinnars, and J. Wernerman. Long-term effect of glycyl-glutamine after elective surgery on free amino acids in muscle. JPEN J. Parenter. Enteral. Nutr. 18:320–325. 1994. [PubMed Citation]

49. Rohde, T., D.A. MacLean, and B.K. Pedersen. Effect of glutamine supplementation on changes in the immune system induced by repeated exercise. Med. Sci. Sports Exerc. 30:856–862. 1998. [PubMed Citation]


[/ QUOTE ]

This study reveals in the observable world glutamine does work, but the emperical scientific reseach to understand why, and all the variables, constants, and controls, need to manipulate these results in the lab, are not yet understood.

To quote Cyber Internationals:

[ QUOTE ]
<font color="red"> Despite progressive resistance’s long history, relatively little scientific information has been published regarding various training techniques and their effects on muscle mass.

A large part of the information concerning weight training has been gained through practical experiences and empirical observations of bodybuilders. The current body of scientific information regarding weight training’s effects on muscle mass is s

[Venom]

That was excellent Old School. /forum/images/graemlins/smile.gif

[William Ustav]

I take it back - ADAM will post studies to prove the opposite! /forum/images/graemlins/wink.gif

Insanely awesome!

[Fireproof]

I knew one of our distinguished mods would post a proper response. (Hence the deletion of my not-so-scientific post above. /forum/images/graemlins/wink.gif )

[RGKfit]

[ QUOTE ]
Interesting,

well read this, and hopefully soon you'll be convinced

Glutamine
Destroying the Dogma, Part 1
by David J. Barr


One of the most frequent supplement questions I get as a strength coach is whether or not athletes should use the amino acid glutamine for either performance enhancement or size gains.

The topic comes up so much that it almost seems as though glutamine is a "no brainer" supplement just like creatine. In fact, its popularity is such that at least two separate online message boards, as well as numerous magazines, have feature articles on the use of glutamine as a supplement. The dogma of glutamine supplementation had even permeated the SWIS symposium to the extent that the numerous conversations about this amino acid were solely about how much to take, rather than whether or not to take it.

So, it seems as though everything is pretty cut and dried when it comes to glutamine use… or is it? While there was some literature-supported speculation as to the potential benefits of glutamine supplementation, there needs to be an updated review of the literature examining the current status of this purported "wonder supplement." In fact, there's quite a bit of information that's been left out of the popular bodybuilding literature that needs to be brought to light.

But before we get on to that, we should review some of the basics of glutamine.


Glutamine: The Basics

For those of you who are new to the concept of glutamine supplementation, you should know that it's a non-essential amino acid created largely by our muscles. It's also noteworthy that glutamine is the most abundant free amino acid in our bodies, comprising up to 2/3 of the muscle free amino acid pool.(13) This fact, coupled with the idea that muscle is the largest producer of this amino acid, could suggest that supplementation would be beneficial.

One potential problem with this is that glutamine is a non-essential amino acid (meaning that we don't have to consume outside sources containing this amino acid because our bodies can make it on its own), but this is where things get interesting: the use of glutamine by many different cells in our bodies is so great that there may be times when its use exceeds its availability, therefore glutamine has been termed a "conditionally essential" amino acid.(18)

This means that during times of physical stress the body may actually need glutamine from the diet to maintain proper cellular function. Clearly, activities such as resistance training constitute a physical stress on the body, which is one reason that athletes have been targeted for glutamine supplementation.

Another interesting fact about our muscles and glutamine is the issue of transport. For an amino acid to get into or out of our muscles, it has to be transported by specific carriers. Using these carriers, our muscle takes up amino acids according to demand from protein composition (i.e. what our muscles need the most), BUT amino acid release is NOT according to composition.

Alanine and glutamine can account for up to 50% of amino acid release from muscle despite accounting for only about 15% of total muscle protein.(31) Obviously, this is a huge discrepancy—which is normally made up for through glutamine production—but as mentioned earlier, during times of physical stress (i.e. exercise), the synthesis of glutamine is hindered. Everyone knows that lacking even one amino acid can hinder muscle growth, which fortifies the theory of glutamine supplementation by athletes.

Now that you're familiar with the basics behind glutamine supplementation, it's time to delve into the literature and pull out some more specific theories as to the beneficial effects of glutamine supplementation.


Glutamine and Muscle Mass

Interest first arose in glutamine as a supplement when it was found that glutamine enrichment elevated levels of protein synthesis in isolated rat muscles.(21) This isn't surprising since it's also been found that muscle protein synthesis levels can be correlated with free glutamine levels.(17) It's also been shown in vitro using rat skeletal muscle cells that glutamine may decrease protein breakdown.(22)

Additionally, we know that the anabolic/catabolic state of a muscle cell is related to it's hydration status—this simply means that cellular swelling has an anabolic or an anticatabolic effect on the affected cells (including muscle cells). Based on this, it's been found that glutamine supplementation may mediate cell swelling and therefore an anticatabolic effect through either increasing cell swelling or hindering cellular dehydration.(28)

Sure you say, these theories are all well and good in cell cultures or animals, but what about the human studies? Well, studies in humans indicate that glutamine supplementation may improve nitrogen balance in critically ill patients, as well as assist in the prevention of protein synthesis decreases following surgery (a HUGE physical stress) or following a 14-hour fast.(13, 12,24,13) There have even been a couple of studies done on resistance trained subjects (more on that a little later)!


Glutamine and Overtraining

We've all felt the scourge of overtraining: the lethargy, the sickness, and the lack of desire to train. Aside from the horrible feeling associated with overtraining, we also know that the longer we're out of the gym, the longer we go without any anabolic stimulus to our muscles. Based on this, another theory suggesting glutamine supplementation for athletes involves the prevention of overtraining.

Glutamine is used as a fuel source by many cells of our body, including many cells of our immune system. Now if you recall that there are times of stress where the body's production fails to meet its needs for glutamine, you can see that this could negatively affect the immune system. In fact, you may not be surprised to find that blood glutamine levels may be compromised following exercise induced overtraining.(1)

Surveys of endurance athletes supplementing with glutamine following a marathon race showed lower rates of infection than those who didn't supplement.(8,9) As for the applicability to bodybuilding, one study showed that resistance exercise may induce a small transient (ie short-term) negative effect on some cells of the immune system, although plasma glutamine levels weren't examined.(6)

So now we have theories for glutamine supplementation to increase protein synthesis/inhibit protein breakdown, as well as boost immunity following intense exercise. This sounds great, but we have yet to look at glutamine's potential effect to stimulate glycogen replenishment following exercise. Glutamine infusion has been shown to enhance glycogen stores following cycling exercise twice as much as compared to subjects who infused saline or other amino acids.(27) If this happened after weight training, it could even help with our cellular swelling and have the aforementioned postive effect on protein accretion.

Another study supports the use of glutamine for enhancing muscle glycogen. Bowtell et al. found that glutamine supplementation following exercise enhanced glycogen resynthesis in muscle just as well as the ingestion of a glucose polymer.(4)

Sadly at this point, many readers have already gone out and bought their kilos of glutamine, and are now reading only to find out how to use the stuff. You may argue, why not? There's plenty of evidence to support the theories presented! This was exactly the thinking when glutamine was introduced to bodybuilders several years ago. In fact, the journal articles reviewed above are the same research papers that can be found time and again, in any outdated article that's trying to sell you on glutamine. But things have recently changed; new studies have been done on animals, and people involved in resistance training, but the results are less than positive.


What the Glutamine Salespeople Don't Want You To Know:

Glutamine and Protein Synthesis — The other side of the coin

We've seen the theory that glutamine levels in the blood and muscle may decrease during or following exercise, and that this decrease correlates with reduced levels of protein synthesis. Several studies have addressed whether this relationship between glutamine and protein synthesis was a coincidental or a causal (meaning that one caused the other) relationship.

The first study compared the abilities of glutamine and the amino acid alanine to stimulate protein synthesis in rats with artificially reduced blood and muscle glutamine levels.(23) As expected, glutamine infusion increased intramuscular glutamine levels, while alanine didn't. Surprisingly, even depleting muscle glutamine levels by 60% had no effect on protein synthesis. What may also surprise you is that restoring blood and muscle glutamine levels to normal had no effect on protein synthesis compared to rats receiving no glutamine treatment! Additionally, even though whole body protein turnover didn't change, alanine stimulated protein synthesis!

In support of this contention, researchers studied the effect of glutamine supplementation on septic rats. Sepsis is a severely catabolic condition, during which glutamine levels (and protein synthesis) fall. Again, this study showed that despite increasing muscle glutamine levels to even higher than normal, it had no effect on protein synthesis or the catabolic state of the rats.(11)

Cumulatively, these studies show that decreased or increased levels of glutamine in the muscle has no effect on protein synthesis.

Another study, performed on people, examined the effect of adding glutamine to an amino acid mixture on muscle protein synthesis .(30) Ultimately, infusion of the original amino acid mixture increased protein synthesis by nearly 50%, but adding glutamine to this mix had no additional effect. This study is particularly relevant because most consumers of glutamine do so following a workout, along with other amino acids (or a whole protein).

Finally, Wusteman et al., used a drug to reduce muscle protein synthesis, along with muscle glutamine levels, in rats.(29) Much like the Olde Damink et al. study, restoring muscle glutamine levels to normal had no effect on protein synthesis. This study further supports the concept that blood and muscle glutamine levels have no bearing on protein synthesis and protein turnover.


Editor's note: Part 2, which pretty much presents a case for relegating glutamine to the Retired Supplements shelf (except for very specific circumstances) will be posted next week.


David J. Barr, CSCS, MSc. Candidate, is a Varsity Strength and Conditioning Coach at the University of Waterloo



[/ QUOTE ]

I read this by David Barr about a year ago. I believe it was published in Testosterone mag or on the BB website, I forget which. Need more be said?

[**DONOTDELETE**]

[Breaktrack]

OH man my brain hurts

[Audiowaves252]

good point oldschool... but so many people waste their $$ on supplements just because it says "increased muscle recovery" or whatever or on the label, in hopes that its actually going to make a difference.

My main point is... (to save you guys money)

Glutamine is indeed the most abundant free-form amino acid in the body. So abundant in fact, it would take 6 days of intense weight training and 5 days of intense (HIIT style) cardio to deplete basal glutamine levels enough to need outside supplement. The body will not use supplemented glutamine unless its own stores are drastically depleted.

2) Metabolism 2000 Dec;49(12):1555-60 Related Articles, Links

almost every protein powder contains a nice amino acid profile, including a good amount of glutamine, so you're already restoring basal levels, not to mention if you eat dairy products, beans, etc. you're also building stores back up, so hyw pay $40 for 400 grams?


[ QUOTE ]
I take it back - ADAM will post studies to prove the opposite! /forum/images/graemlins/wink.gif

Insanely awesome!

[/ QUOTE ]

He made a good point, yet did not prove the opposite.

[**DONOTDELETE**]

[Audiowaves252]

[ QUOTE ]
OH man my brain hurts

[/ QUOTE ]

lol

[Audiowaves252]

[ QUOTE ]
. Ergo, glutamine is not worthless. Keep in mind though, it's not a miracle supplement either - there is no such thing. But glutamine supplementation is beneficial for the bodybuilder.

[/ QUOTE ]

I take it you have used glutamine and had results from it.
Ahhh the power of placebo.

[Adam Knowlden]

[ QUOTE ]
My main point is... (to save you guys money)

[/ QUOTE ]

That logic makes no sense. That is a false analogy. You have yet to reveal anything aside from your belief in your own circular reasoning.

You have made this false analogy.

Do not buy glutamine &gt; You will save money!

The same logic can be applied to any supplement. Because not buying glutamine will save you money does not mean it is not an effective supplement.

[ QUOTE ]
I take it you have used glutamine and had results from it.
Ahhh the power of placebo.

[/ QUOTE ]

The study I provided had a placebo group, and the group supplementing with Creatine and glutamine gained LBM while the placebo gained little.

[ QUOTE ]
This finding is significant in that glutamine supplementation is very popular among strength power athletes (36) and often suggested to enhance the ergogenic effects of creatine supplementation (17).

In the present study, it was hypothesized that both the CM and CG would result in significantly greater increases in body mass based on consistent findings of a 0.9- to 3.8-kg increase in body mass with creatine supplementation in the scientific literature (3, 4, 13, 16, 19, 20, 35, 38, 39). In the present study, the CM and CG treatments resulted in a significantly greater increase in body mass (CM: +1.7 kg; CG: +2.3 kg) than the P treatment (P: +0.2 kg) over the 8 weeks of supplementation. Generally, the increases in body mass associated with long-term (&gt;8 days) creatine supplementation regimens have been suggested to be a result of increases in protein synthesis (3, 18, 55), which may be manifested as LBM gains. The results of the skinfold data in the present study suggest that both CM and CG supplementation resulted in significant increases in both body mass and LBM when coupled with a strength and conditioning program. These data are in agreement with previously reported research, which suggests that creatine monohydrate increases LBM (22, 55, 63). Based on these findings, CG and CM supplementation regimens have the potential to magnify the body mass and LBM adaptations to a structured strength and conditioning program.


[/ QUOTE ]

You are now attempting to avoid the topic with ad hominems and red herrings.

Instead of addressing the 2003 study, and the studies Yu presented, you attack Yu with ad hominems.

Rather than dealing with the opposing arguments from the studies, you use card stacking techniques and falsely claim "placebo". That type of arguement is irrelevant to validating the given conclusion and is fallacious.

The burden of proof is on you to show glutamine is "worhtless", not us. Your claim that glutamine is "worthless" is clearly unsubstantiated.

[ QUOTE ]
So abundant in fact, it would take 6 days of intense weight training and 5 days of intense (HIIT style) cardio to deplete basal glutamine levels enough to need outside supplement. The body will not use supplemented glutamine unless its own stores are drastically depleted.


[/ QUOTE ]

This makes no sense. Is this 24 hours straight? What are the controls of this claim? Where is the reference?

[ QUOTE ]
2) Metabolism 2000 Dec;49(12):1555-60 Related Articles, Links

almost every protein powder contains a nice amino acid profile, including a good amount of glutamine, so you're already restoring basal levels, not to mention if you eat dairy products, beans, etc. you're also building stores back up, so hyw pay $40 for 400 grams?

[/ QUOTE ]

So now glutamine is not worthless? Here you are saying it's "nice amino acid profile, including a good amount of glutamine." So, it is not worthless.

And this is not a research journal, this is a advertiser's magazine: "Metabolism 2000 Dec;49(12):1555-60"

Also the study Yu and I presented is a actual journal study from 2003, revealing glutamine is helpful supplement, but that much more research needs to be done to understand the full potential of glutamine, as this is the first case study of its kind, while you provided a 1999 article that begs the question, and jumps to hasty false generalizations.

[President Wilson]

Outstanding breakdown on those studies Yu Yevon and Old School! Very insightful!

[President Wilson]

They also provided an excellent learning experience on how to dissect studies. As well as extreme insight, along with fantastic explanations on double blind placebos!

[alanlws16]

Dang, Yu had like a page and a half of references on his!

[**DONOTDELETE**]

[alanlws16]

That last point is really enough reason to use it.

[Adam Knowlden]

Thanks for the studies Yu Yevon! Those were off the hook!

[ QUOTE ]
We conclude that in Caco-2 cells, protein synthesis depends on nutrient supply on the apical side, and glutamine regardless of the route of supply corrects some of the deleterious effects of fasting in a model of human enterocytes through its deamidation into glutamate.



[/ QUOTE ]

That is excellent news for the post workout scenario!

Glutamine is defenietly not worthless. Current studies are proving its effectiveness. I reviewed all of the studies that were mentioned in the intial article that was copied and pasted from that advetiser.

He made up his conclusion devoid of the true essence of the journals sited. He did terrible research.

Not one of the authors "insights" revealed the actual conclusions the researchers had made in their journal entries.

[Aidan]

***** me, if i read all that, I am bound to have read more information my 5yrs of english at highschool!!

No need to convince me, I'll do whatever abc nutrtion tab tells me to do /forum/images/graemlins/wink.gif

[Fireproof]

[ QUOTE ]
I could go on, but I think you get the idea. I believe we have effectively busted the "glutamine = worthless" myth.

[/ QUOTE ]

Yup - I'm convinced! Now pardon me, while I go take a teaspoon of glutamine! /forum/images/graemlins/wink.gif

[Venom]

Excellent information guys. /forum/images/graemlins/smile.gif

[OUTLAW20SICX]

can i get that summarized

[**DONOTDELETE**]

[Breaktrack]

[ QUOTE ]
[ QUOTE ]
can i get that summarized

[/ QUOTE ]

Glutamine is not worthless and is a great supplement for bodybuilders and other athletes.

[/ QUOTE ]

Kick *** summary buddy

[Adam Knowlden]

[ QUOTE ]
Glutamine is not worthless and is a great supplement for bodybuilders and other athletes.


[/ QUOTE ]

Yu has a part time job writing cliff notes!LOL /forum/images/graemlins/wink.gif

[President Wilson]

[ QUOTE ]
[ QUOTE ]
Glutamine is not worthless and is a great supplement for bodybuilders and other athletes.


[/ QUOTE ]

Yu has a part time job writing cliff notes!LOL /forum/images/graemlins/wink.gif

[/ QUOTE ]

Joe is the man!

[Andrew G.]

Im starting to question the mortality of the moderators on this board. It wouldnt be a huge surprise to me if you guys turned out to be divine beings... ya'all just know to much!

I can just see Joe, Adam, Jacob, Venom (dont know your name buddy!), Tuff as god's personal trainers... well... rather training partners.

[OUTLAW20SICX]

where do yall find this info

[Adam Knowlden]

[ QUOTE ]


Im starting to question the mortality of the moderators on this board. It wouldnt be a huge surprise to me if you guys turned out to be divine beings... ya'all just know to much!

I can just see Joe, Adam, Jacob, Venom (dont know your name buddy!), Tuff as god's personal trainers... well... rather training partners.


[/ QUOTE ]

LOL! Thanks, but we owe everything to God, we're nowhere near divine. Actually I would give up any and all my abilities to be a perfect servant of the Lord.

But our real purpose,and the focus of this site, is to provide the members the latest up-to-date science regarding bodybuilding. No hype or marketing tactics, just the facts.

[Jenn]

[ QUOTE ]

LOL! Thanks, but we owe everything to God, we're nowhere near divine. Actually I would give up any and all my abilities to be a perfect servant of the Lord.

But our real purpose,and the focus of this site, is to provide the members the latest up-to-date science regarding bodybuilding. No hype or marketing tactics, just the facts.

[/ QUOTE ]

And we can't thank you all enough!

[OUTLAW20SICX]

you guys should make a cliffs notes section, lol

[given_to_fly]

[ QUOTE ]


LOL! Thanks, but we owe everything to God, we're nowhere near divine. Actually I would give up any and all my abilities to be a perfect servant of the Lord.

But our real purpose,and the focus of this site, is to provide the members the latest up-to-date science regarding bodybuilding. No hype or marketing tactics, just the facts.

[/ QUOTE ]

just saw this post now, thought it was worth a bump as well...
but i must really say... wow. you guys rock!

[TexasMade]

not worth the money if youre on a budget imo, but it works for a lot of people so just another choice youll have to make in the world of supplements.

[Jabberjaw]

Hmm...

[Bluenose]

Good bump GTF!

I stopped reading the first one when it found that there was no short term benefit. Most of the members here aren't in it for the short term so it wasn't even relevant.

I'm not goiong to run out and get any glutamine, but it was good to read.

Jeff.

[Adam Knowlden]

[ QUOTE ]
not worth the money if youre on a budget imo,

[/ QUOTE ]

If you're on a budget save it for PW. Studies are showing glutamine can increase glucose uptake PW! /forum/images/graemlins/shocked.gif

[eugen]

we are still behind any final word on supplements we are taking.
Maybe we are the testing rats , who knows.

[aquariyums]

[ QUOTE ]
I used free form L-Glutamine while on my cut and I sure lost some muscle mass. Next time I'm not going to waste my money.

[/ QUOTE ]

The only reason I am taking it is because I bought some a while ago, when it runs out I won't buy anymore. I only take whey and creatine. thats all that I need/want.

[Coz]

[ QUOTE ]
we are still behind any final word on supplements we are taking.
Maybe we are the testing rats , who knows.

[/ QUOTE ]

No we are not, we have all the evidence on Glutamine, if you read the article you will see the references. Reviving this thread was unnecessary since there is another one just like it posted recently.