I have evaluated in my experience glutamine helps with recovery too.. and it helps with immune system. I haven't been sick in a long time thank God. And every time i feel I am almost getting sick (like last few days) I load up on glutamine every few hours, take vitamin c, and sleep.. sweat.. and take a bit of care and continue glutamine and im good to go.
It's amazing for immune system... and it does help with recovery but u gotta dose it high and consistently. Hence I get 1kg raw bulk powder of it.