Glutamine is a heavily pushed supplement in the bodybuilding community. Is glutamine all hype or does it really work?
What is glutamine?
Glutamine is a nonessential amino acid with multiple roles in the body, especially in building muscle and digestive health.
Why do bodybuilders supplement Glutamine?
Glutamine is the most widely used amino acid by the body for building muscle. Post workout there is a huge drop in glutamine levels as the muscles use it for protein synthesis. This implies there is a need for glutamine. It is this reason why glutamine supplementation is advocated by some.
Glutamine may sound like a miracle muscle builder, but there is some things we have to remember. During a bulk phase you will be eating a lot of protein, therefore getting a lot of glutamine already. Since it is a non-essential amino acid, the body will also be able to quickly manafacture the extra glutamine it needs postworkout. The intestinal gut also takes a particular liking to glutamine. In fact about 90% of glutamine is absorbed directly by the intestine to be used for energy. So, in essence most of the glutamine you take, just goes down the toilet anyways!
A few studies have been done on glutamine to help us answer if Glutamine works.
A study done by Candow published by Eur J Appl Physiol 86:142-149, 2001 had 31 volunteers do resistance for 6 weeks. One group supplemented glutamine at high doses(0.4 grams per lb of lean muscle), while the other had maltodextrin. Both groups gained muscle at the same rate.
Another study published in J Strength Cond Res 17(3):425-438, 2003 had 29 on a strength training program. They were in 3 groups, creatine only, placebo, and glutamine and creatine. Both creatine groups gained muscle more than placebo, however no difference between the non-glutamine and the glutamine creatine combo. A seperate study in that issue J Strength Cond Res 17(4):810-816, 2003, using ribose, glutamine, and effervescent creatine showed no difference with the glutamine group.
Glutamine has also been suggested as a supplement that is better for dieters. The reason is due to some research on glutamine during stress situations. What does science say about that? The only study I could find on muscle preservation during dieting, is published in Journal of Sports Science and Medicine (2003) 2, 163-168. The researchers had 18 athletes for 12 days on a weight loss program, with half taking glutamine(0.16 g/ lb of bodyweight). They found no difference in muscle retention between the glutamine and non glutamine group.
According to the research, Glutamine supplementation is a waste of money, whether bulking or cutting. Glutamine supplementation may have other health benefits; such as maintaining gut health and immunity and helping those with illnesses.