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[trickbikeguy dave]

This will be the first part of what may be a multi-part group of postings.  Clara and I intend to start reviewing supplements.  Rather than picking one particular brand, I am starting out by addressing glutamine in general, which is a component in many supplements.  In the future I may review specific supplements, but for now I will start with Glutamine.

What exactly is glutamine?  L glutamine is the most abundant amino acid found in human muscle and plasma.  Guess what?  You will find glutamine in nearly all protein powders.

But a lot of people are under the myth that glutamine will help them recover better from a hard workout or build muscle or something else.  The reality is that the science just doesn't support glutamine being effective for much other than gastric diseases and other stuff that really isn't the focus of the fitness industry.

In a nutshell, glutamine has consistently failed at all of the hyped fitness-related claims.  So, do not waste your money buying glutamine supplements.  BCAA is a precursor for glutamine synthesis within the body, so a protein-rich diet common to anyone following the BFL program provides you with plenty of BCAA, provides enough material for endogenous glutamine synthesis. Regarding recovery, think again, & save your money. Let me quote a couple of sections of a recent review on glutamine:


See, Glutamine: the nonessential amino acid for performance enhancement Phillips GC.  Curr Sports Med Rep. 2007 Jul;6(4):265-8.  

“Even using protein breakdown as a measure of recovery, the effects of glutamine are mixed at best. Though one investigation demonstrated an inhibition of total body proteolysis as measured by improved leucine flux after glutamine supplementation [21], a separate study showed glutamine supplementation did not affect urinary levels of 3-methylhistidine, another marker of protein degradation [14]. Therefore, whether considering buffering capacity, time to fatigue, or protein balance, glutamine supplementation fails to consistently demonstrate any positive ergogenic benefit on measures of recovery from exercise.
Unfortunately, this appears to be another example of commercial marketing trumping scientific evidence that in this case demonstrates how nonessential glutamine supplementation is to athletic performance

Glutamine has consistently failed to increase strength and lean mass:

Addition of glutamine to essential amino acids and carbohydrate does not enhance anabolism in young human males following exercise. Wilkinson SB, Kim PL, Armstrong D, Phillips SM. Appl Physiol Nutr Metab. 2006 Oct;31(5):518-29.

"The addition of glutamine to a CHO + EAA beverage had no effect on post-exercise muscle glycogen resynthesis or muscle protein synthesis, but may suppress a rise in whole-body proteolysis during the later stages of recovery."



See also, Effect of glutamine supplementation combined with resistance training in young adults.
Candow DG, Chilibeck PD, Burke DG, Davison KS, Smith-Palmer T. Eur J Appl Physiol. 2001 Dec;86(2):142-9. Abstract available at: http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=11822473&ordinalpos=16&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum

“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.”


Facts and fallacies of purported ergogenic amino acid supplements. Williams MH. PMID: 10410846
"Although glutamine supplementation may increase plasma glutamine levels, its effect on enhancement of the immune system and prevention of adverse effects of the overtraining syndrome are equivocal."




Amino acids and endurance exercise.
Hargreaves MH, Snow R. School of Health Sciences, Deakin University, Burwood, 3125, Australia. PMID: 11255141

"...there is little support from controlled studies to recommend glutamine ingestion for enhanced immune function, and although glutamine stimulates muscle glycogen synthesis, its addition to carbohydrate supplements provides no additional benefit over ingestion of carbohydrate alone."

The Effects of High-Dose Glutamine Ingestion on Weightlifting Performance JOSE ANTONIO, et. al.

"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."


One claim has been that glutamine helps promote glycogen storage.  A 2000 study showed that whey protein actually caused greater rates of glycogenesis.  The study also showed that wheat protein also caused greater rates of glycogenesis than glutamine.  It should be noted that the wheat hydrolysate (which contained 26% glutamine) and the whey hydrolysate (which contained 6.6% glutamine) both contain less glutamine than casein protein.
See, 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. Int J Sports Med. 2000 Jan;21(1):25-30. PMID: 10683095 abstract available online at: http://www.ncbi.nlm.nih.gov/pubmed/10683095?ordinalpos=7&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum

[StephanieWorkman]

Fabulous!

I'll look forward to reading your reviews!

Stephanie

[Kerryn Woods]

While there are many supplements out there that are a complete waste of money, I beg to disagree on this one. In a big way.

Glutamine has many benefits that are of vital interest to the fitness industry. The reduction in muscle soreness theory (which is the reason many, if not most people, take it) is probably unproven - some studies support it, others don't. The thing about studies is that they don't (can't) take into account the effect of each individual's genetic profile. Some people will always get more benefit from a particular product, exercise protocol or nutrition program than others.

I take glutamine for a number of reasons, the main one being immune system support. To quote a good friend of mine, Sara Lake - who's a NZ BFL champion, certified PT, supplement guru and nutrition scientist:

How many times have you begun a heavy training program only to be sidelined by a cold? Glutamine is the primary nutrient for your immune system and low Glutamine levels can leave you vulnerable to illness right when you most want to be fighting fit! 

I almost never get sick. I train hard, I eat well, and I take my glutamine and Vitamin C, and I credit those two supplements with my robust health when the rest of my family are stricken with the snot-bug or a nasty gastro virus, or something else equally contagious. Without the extra glutamine, my immune system would struggle.

I also have fairly ordinary recovery genes, and I know that I do better when I take my BCAAs and glutamine, pre- and during my workouts. If I miss either or both, I know about it! Sure, there are other things I do tohelp with my recovery, but no one thing works in isolation.

There's a longish list of other benefits, among them the supressing of cravings, healthy digestive function, and possibly a positive effect on insulin levels.

The Australian Institute of Sport routinely uses it for their athletes - and there aren't many products that they endorse. You know governments, cautious to ridiculous extremes.

And it's a very cheap supplement - at least it is here - so whether or not it's absolutely essential, it's not likely to send anyone broke.