Hi Rob,
I don't take it by bodyweight but by total amount of glutamine (30 g), but that turns out to exactly match the recommendation below. I found the quote on another board as this sparked my interest to have a decent answer. I will say that I used to become overtrained way too easily before I started supplementing with glutamine. Don't know if I have some other issues going on but the Glutamine definitely helped. Here's the info:
Dr. Eric Serrano on Glutamine:
"Glutamine has made a big difference in my patients, especially their immune systems, and glutamine gets rid of colds; it helps your joints; and it can increase your strength in one day. People will ask me where I'm getting this information from, but I've been playing with 11 patients with different dosages. Here's what I've come up with: you need .35 grams per kilogram of body weight. And you take it in one dose an hour before a workout.
I know that we chemistry people say it does this or it does that, but something else is going on. I think there are two mechanisms. For one thing, I think it's an excellent source of energy because the body can break it down to glutamic acid, which is kind of a sugar [although he wouldn't come right out and say it, Dr. Serrano intimated that the glutamic acid may serve as a powerful energy substrate, thereby increasing work capacity]. Number two, I have found out, and this is very important, glutamine is a marker of overtraining. If I take people, and I have them write down their workouts, and if their glutamic acid/glutamine ratio is over 10 to one, that person was invariably getting sick or developing soreness, or their performance was going down. I will tell you, papers are going to come out on it, because it's very interesting how this works. If the ratio is less than 10 to 1, you're overtraining. If I give you oral glutamine, you'll prevent overtraining. I have some theories about how it works, but I don't want to talk about them yet…if it works that way, great, but I don't want to give people the wrong idea.
Because the cost is so high, I wouldn't take it every day. I might take a baseline dosage of 2 to 5 grams a day to keep my levels high, but if I'm going through an intensity phase or accumulation phase, like Charles Poliquin calls them, I will take a larger dosage—.35 grams (times body weight in kilograms) and divide it into two dosages; in the morning, an hour before the workout, and the other half before bedtime to preserve muscle while I'm sleeping."