An Undeserved Reputation
For the last couple of years I’ve completely dismissed glutamine as a supplement, mainly because certain internet gurus take pleasure in demonising or worshipping certain supplements. Glutamine was one of the persecuted ones, and everyone jumped on the bandwagon. Since I reintroduced it I’ve had better workouts, recovered more easily and slept better.
So here’s some pretty cool info that changed my mind on the supplement:
1- Cellular hydration:
Glutamine plays a crucial role in cellular hydration and leucine uptake: Glutamine-depleted cells shrink, which is catabolic and associated with cell-volume dependent mTOR downregulation.
From [1]:
“Our results indicate that diverse control signals converge on the mTOR-S6K1 signaling pathway. In the presence of adequate energy resources, the pathway senses the amino acid availability as inward transport of effective amino acids (as BCAA and especially leucine), but its activation occurs only in the presence of an extracellular amino acid complement, with glutamine as obligatory component, and does not tolerate decrements of cell water volume incapable of maintaining adequate intracellular physicochemical conditions.”
Bill Willis points out in his article on cellular hydration:
“• Glutamine is needed for leucine to gain access into the cell to turn on protein synthesis.
• Glutamine induced cell volumization is necessary to turn on mTOR and protein synthesis.
• Cells need to be preloaded with glutamine. “
Bill’s article is worth a read, and gives some interesting insights on the uses of EAA, beta alanine etc.
2- Low plasma glutamine levels are a predictor of exercise stress and overtraining:
While it may or may not follow that taking in more glutamine will delay the onset of overtraining and exercise-induced stress, we do know that plasma levels are acutely depleted during overtraining (muscle glutamine levels appear to be less predictable).
3 – Glutamine positively affects plasma growth hormone and IGF-1, improving memory in elderly subjects.
Small oral doses have this effect [4]. IGF-1 and growth hormone are also essential for muscle building and fat loss.
4 – Glutamine and GABA: Anxiolytic (Anti-anxiety) effects
Glutamine is a precursor for GABA synthesis, and therefore ‘may provide a useful adjunct for treating disorders (e.g., anxiety, seizures) when enhanced GABAergic transmission is desired.’
[5]

5 – Glutamine Enhances Muscle Glycogen Synthesis
Glutamine increases whole body glycogen storage [6], [7]. See the recommendations below for how to exploit this.
6 – Glutamine (and BCAA) can help reduce DOMs and recover glutamine concentration
Glutamine and BCAA during a workout have separately been shown in trials to reduce a) soreness, b) muscle damage and c) decrease in performance during workouts. [8][9][10]
7 – Gastric Health:
This article discusses glutamine’s anti-catabolic role during sickness, intestinal repair and anti-ulcer properties. This makes it a good choice for those doing relatively long fasts to protect the stomach wall in healthy individuals. Despite theoretical indications of glutamine’s ability to treat Crohn’s (Inflammatory Bowel) Disease, research showed no significant improvement in sufferers. So it’s not magic… but it’s close.
Putting it all together – Recommendations:
I’m a supplement minimalist, and while you could make several additions to the following concoctions to make them more effective, I feel the cost wouldn’t justify the benefit. Anyway, this article was supposed to be about glutamine, so here’s how to use it in the contexts we’ve discussed:
For improved sleep and recovery:
Before bed:
– 10g L-Glutamine
– L-Theanine, Phenibut (Use code PRFT5OFF for 5% off MindNutrition products).
Intra-Workout:
– 15 grams Glutamine
– BCAA [13] (I use 20g MP Exceed, one of my favourite supplements) which has electrolytes, beta alanine and citruline malate, all of which improve this cell volume situation as well as buffering fatigue.
– Maltodextrin – Between 20-100g depending on training volume, goals, bodyweight etc.
– 3 litres of water sipped throughout your session. Intracellular hydration is separate to getting a ‘pump’ (extracellular hydration), so don’t fret if you’re not pumped. Insulin also helps the process, hence the maltodextrin.
Post-Workout:
If training volume or intensity was high, it would be prudent to add another 15g glutamine here during your carb refeed a la Propane Protocol to fill muscle glycogen for the next training session.
Maintaining Stomach Health During Alternate Day Fasting (ADF)
:
Take 20g glutamine before starting the fast.
NOTES:
– Don’t use Glutamine peptides, it is just hydrolysed wheat protein, which is high in gluten and may cause stomach upset. It’s also more expensive.
– Also, about the affiliate links: Here’s how it happens: we personally use and love certain products, so we decide to endorse them and spread the word. Not the other way round. We’re painfully aware of crooks in the supplement industry selling all sorts of snake oil, and so we base our recommendations on research and experience only. So if this article has convinced you about glutamine and want to help support us, please buy through the links in this article.
References:
[1] http://www.ncbi.nlm.nih.gov/pubmed/15605414
[2]http://ukpmc.ac.uk/abstract/MED/8775515/reload=0;jsessionid=8piS04T5OUl4Fp06ucr2.0
[3]http://www.ncbi.nlm.nih.gov/pubmed/14609312
[4]http://www.ajcn.org/content/61/5/1058
[5]http://www.fasebj.org/content/21/4/1227.full
[6]http://jap.physiology.org/content/86/6/1770
[7]http://ajpendo.physiology.org/content/269/2/E309.short
[8]http://cat.inist.fr/?aModele=afficheN&cpsidt=20647574
[9]http://jn.nutrition.org/content/136/2/529S.full
[10]http://bjsm.bmj.com/content/44/Suppl_1/i43.2.short
[11]http://www.ncbi.nlm.nih.gov/pubmed/11533302
[12]http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1728161/
[13]http://jeb.biologists.org/content/160/1/149.short
7 replies on “Glutamine Makes a Comeback: 7 Reasons L-Glutamine is Better Than You Think”
Doses over 5g are counteractive to blood GH levels. Take maximum of 5g per 3 hours – the duration of GH boost that glutamine gives when taken plain with water.
DO NOT mix glutamine with other stuff, especially carbs. That will ruin the 100-200% boost to your GH levels. Take it 30 minutes before other stuff, with water and separately from food.
The GH response is insignificant anyway, and it doesn’t alter the total amount of GH secreted over the day. It doesn’t make any difference.
I got really really sick and went from 220 lbs to 170 lbs. I was in a extreme catabolic state but glutamine loading refilled all my muscle cells and in about 4 weeks I had my gains back! I used compounds lift for quick gains like heavy deads power snatches and clean and jerks, bench press.
Sounds good John. Although how do you know it was the glutamine and not the compound lifts and calories?
In reading some of these comments of individuals that have trouble with being hungry I would recommend that they become “keto-adapted” and stay with mostly keto diets when not fasting. No grains, (there is no such thing as a healthy grain) , no bread, pasta, pizza, beer, rice, brown or otherwise. Keep the carbs down to 50 grams or less daily. Obtain your carbohydrates from vegetable sources like spinach, cabbage, broccoli, green beans (no legumes or other beans) . Once you are keto-adapted hunger will hardly ever be a problem and make the fasting days much easier on you.
Thank you very much for sharing this great information about glutamine and its uses. Well I have been using bcaa and whey protein for a long time and have experienced great results from them. Now my trainer is insisting me to start using glutamine for many of its benefits. I am just conscious if there are any side effects to taking the glutamine supplements.
There may well be – documented and undocumented. Worth looking into their page on examine.com for the latest data