I'd like to see the "good" studies you could locate.
I understand you don't know me from a hole in the wall, but whenever someone tells me something I didn't know before, I don't discredit their information.
I use forums such as this as a learning experience.
Here is some interesting stuff for you in case you ever want to rethink your approach:
Glutamine review by Bryan Haycock.
Here are the reasons to take glutamine.
1) Immune support. Supplemental use of glutamine, either in oral, enteral, or parenteral form, increases intestinal villous height, stimulates gut mucosal cellular proliferation, and maintains mucosal integrity. It also prevents intestinal hyperpermeability and bacterial translocation, which may be involved in sepsis and the development of multiple organ failure. One study reported that athletes reported fewer incedences of upper respiratory tract infections while supplementing with glutamine (2 grams) after they ran.
2) Gastrointestinal support. 70-80% of orally administered glutamine is absorbed into the cells of your GI tract. It remains there and is metabolised by those cells without ever reaching the blood stream (image). In sicknesses such as sepsis it has been shown to help improve survival because of improved GI tract function.
Thats pretty much it.
There is no real benefit for someone looking to build bigger muscles. That 10% of dietary glutamine that gets past the GI tract is taken up by the liver where it is converted into sugar (gluconeogenesis) and stored as glycogen in the liver.
Don't let in-vitro research fool you into thinking oral glutamine will have an effect on a healthy individuals muscle mass. Yes, glutamine does regulate protein synthesis to a certain extent under some situations. However, you can't make it happen by taking it orally. Don't let ads with some pro-bodybuilder holding a bottle of glutamine fool you. Even if that pro-bodybuilder is taking it...it isn't doing anything for him either.
Here are a couple good "in-vivo" research studies to start with:
1. 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.
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.
Keep in mind that if you are eating protein powders, especially any thing with whey in it, you are getting plenty of glutamine. The question of glutamines worth in the newsletter centered on its effect on building mass and/or strength, not anything to do with the gastrointestinal track.
In short, only 47-50% of orally administered glutamine can be expected to make it past the liver and other organs, into the blood stream. And only about 10% can be expected to reach extracellular spaces.[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. Journal of Applied Physiology. 1999 Jun;86(6):1770-7] Now, this is the main argument against glutamine. 90% of the glutamine you take orally never even makes it to your muscles. This isn't to say it is wasted. Your GI tract loves glutamine from reasons explained earlier. If you are having intestinal problems nothing is better. If you are trying to increase protein synthesis by loading glutamine, it isn't going to work.
What Lyle McDonald says on the topic, whom I happen to think has the best link between application and science in the exercise/nutrition world:
Glutamine = one of the most overrated and utterly useless supplements for muscle growth. it works great for stimualting protein synthesis IF you toss it into msucle cells in a test tube. it does some nice things with trauma/burn patients. And does less than jack **** orally in healthy humans at even massive doses. it doesn't spare muscle whiel dieting and it doesn't impact on anabolism. yet it refuses to die as a supplement.
Lyle
Appl Physiol Nutr Metab. 2006 Oct;31(5):518-29. Links
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.
Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, 1280 Main St. West, Hamilton, ON L8S 4K1, Canada.
We examined the effect of a post-exercise oral carbohydrate (CHO, 1 g.kg(-1).h(-1)) and essential amino acid (EAA, 9.25 g) solution containing glutamine (0.3 g/kg BW; GLN trial) versus an isoenergetic CHO-EAA solution without glutamine (control, CON trial) on muscle glycogen resynthesis and whole-body protein turnover following 90 min of cycling at 65% VO2 peak. Over the course of 3 h of recovery, muscle biopsies were taken to measure glycogen resynthesis and mixed muscle protein synthesis (MPS), by incorporation of [ring-2H5] phenylalanine. Infusion of [1-13C] leucine was used to measure whole-body protein turnover. Exercise resulted in a significant decrease in muscle glycogen (p < 0.05) with similar declines in each trial. Glycogen resynthesis following 3 h of recovery indicated no difference in total accumulation or rate of repletion. Leucine oxidation increased 2.5 fold (p < 0.05) during exercise, returned to resting levels immediately post-exercise,and was again elevated at 3 h post-exercise (p < 0.05). Leucine flux, an index of whole-body protein breakdown rate, was reduced during exercise, but increased to resting levels immediately post-exercise, and was further increased at 3 h post-exercise (p < 0.05), but only during the CON trial. Exercise resulted in a marked suppression of whole-body protein synthesis (50% of rest; p < 0.05), which was restored post-exercise; however, the addition of glutamine did not affect whole-body protein synthesis post-exercise. The rate of MPS was not different between trials. 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.
And:
Eur J Appl Physiol. 2001 Dec;86(2):142-9. Links
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.
