I take glutamine (L-glu and glu are the same, BTW) before I go to bed, and after training.

There are many ways you can take it, depending on why you are using it. I am using it to maximize recovery and to minimize muscle wasting (since I am now back in dieting mode) ... which is why I use it after training and before bed.

Glutamine peptides are not exactly the same, andthe amount included in a pre-mixed shake is probably minimal.

get yourself 500g of the loose L-glutamine powder and take 1 teaspoon in juice/Crystal light after training and before bed.

That's my advice anyway.