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Benefits of Glycine, Arginine, Theanine, and GABA?

I have seen C.T. mention glycine on this forum before. Can he or someone summarize what it is good for, is it effective and how much to take.

Also mentioning others for training support and also reducing stress:

GABA powder

Are these good for anything, if so, for what and how much is a good dose?

I believe L-Citrulline is used to enhance performance in the gym but I’m not sure by what mechanism.

I remember that L-theanine is for calming down by still being able to focus.

Anyway I got a free 100 gram bottle of each of these and wanted to know which to try and which to ditch.


Glycine has several benefits.

First it is a neurological inhibitor… it calms down the CNS, kinda like GABA does. By doing that you also lower cortisol (another benefit of glycine).

Glycine also increases circulating serotonin levels, which also helps lower cortisol and calm down.

Finally it is, with leucine, the amino acid that increases mTOR activation the most, leading to a large increase in protein synthesis.

I like to use it post workout to lower cortisol and bring the CNS back down. And at the end of the day to more easily relax and recover.

Thanks for the information.

  1. How many grams of glycine is good to take post workout?
  2. Is GABA powder effective?

Anyway, it seems like GABA, glycine and theanine are for calming down, lowering cortisol and Citrulline and Arginine are supposed to improve performance. Is that accurate? They are supposed to raise NO2 so is that basically a vasodilator?

For more info on glycine just use the search bar, CT wrote in depth on it several times. Try that for the other ones too and maybe you get the answer you’re looking for.