What is Glutamine?  The amino acid L-Glutamine is the most abundant free-form amino acid found in muscle tissue. Like other amino acids, L-Glutamine plays a vital role in protein metabolism and muscle recovery. L-Glutamine is not only utilized by muscle tissue, but also in large quantities by the immune system and by the digestive system as well. During periods of intense training, levels of this amino acid can decline and our bodies may not be able to make enough of it. This can result in depleted L-Glutamine levels in our muscles and thus cause muscle-tissue breakdown. Why should I use Glutamine?  As is the goal of many of today's top supplements, including Creatine Monohydrate, L-Glutamine is used in an attempt to boost strength levels, enhance gains in muscle size and strength and prevent muscle tissue breakdown that can occur subsequent to strenuous exercise. By supplementing the diet with L-Glutamine, weight training athletes may be able to prevent muscle tissue breakdown and help promote cell volumization. When glutamine is in short supply, muscle tissue becomes the first to sacrifice it. Thus muscle tissue breaks down which leads to "flat" muscles, less strength and a very unfavorable environment for muscle growth. However, when glutamine is in abundant supply, the opposite occurs. High muscular levels of glutamine and other cell volumizes like Taurine, can lead to protein metabolism and cell volumizing. Cell volumizing is a process whereby water molecules are pulled into the muscle cell, helping them look "fuller" or more "pumped" and thereby creating the necessary conditions for muscle growth.  What research has been done on Glutamine?  Recent scientific studies on L-Glutamine, and the Amino Acid Taurine, have shown that glutamine can improve protein metabolism and minimize the breakdown of muscle tissue in people suffering from severe metabolic stress. In addition, supplementing with glutamine also was shown to increase cell volumization. Another recent study found that consuming as little as 2 gm of free-form L-Glutamine may cause up to a 400% increase in growth-hormone levels. At this time though, no studies have been done on L-Glutamine's effects on healthy weight training athletes.  What doses of Glutamine should be taken?  While there is no definitive guide on how much L-Glutamine should be taken, supplementing one's diet with as little as 2-6 grams per day may have significant effects on protein metabolism and cell volumizing. Similar to Creatine, L-Glutamine seems to have a "loading period" whereby taking higher doses of this amino acid, sometimes as high as 10-15 grams per day, may cause a rapid increase in cell volumization and muscle hardness thus leading to greater muscular gains.   What side effects are caused by Glutamine?  As of yet, no known side effects have been reported from the use of free form L-Glutamine. L-Glutamine is a natural amino acid produced by our bodies and is believed to be safe.  Should I cycle Glutamine?  L-Glutamine is produced naturally by our bodies on a daily basis. When we perform intense, rigorous exercise, these natural stores of L-Glutamine may be compromised which can lead to muscle breakdown. Therefore, cycling L-Glutamine is not necessary because low levels of L-Glutamine in our bodies can lead to impaired protein metabolism and tissue breakdown. Many manufacturers include L-Glutamine in their meal replacement powders and other products to help boost glutamine intake.