Grenade Essentials Glutamine is a 100% Pure L-Glutamine powder. It is made with the purest form of L-Glutamine. This is an essential amino acid. It is also required by our muscles. It is one of the most vital building blocks in forming proteins. This can help with repair of muscle tissue and protein synthesis. Glutamine is found in many forms of protein. Mostly in Whey Protein and Casein. Supplementing glutamine as a post workout can help restore amino levels that are diminished during training.