GPLC is a propionyl ester of carnitine (PLC) that also contains a glycine component. PCL develops its powerful effects in muscle tissue, including the heart muscle. GPLC exhibits powerful antioxidant properties that counteract free radicals and it also limits lipid peroxidation. It plays an important role in energy production by acting as a vehicle for the transport of fatty acids into the mitochondria and as a vehicle for the removal of waste products from the mitochondria. GPLC maximizes muscle function by compensating for reduced oxygen availability during periods of physical exertion and it provides effective support for blood flow in the arteries. During states of reduced oxygen availability, GPLC also supports normal carbohydrate metabolism and minimizes the formation of lactic acid. A study conducted at the University of Memphis under the direction of Richard Bloomer showed that glycine-propionyl-L-carnitine (GPLC) supplements (GlycoCarn: 3 grams per day in combination with 1,044 milligrams of glycine over four weeks) increased nitric oxide production in weight-training men. The scientists restricted the blood supply to the arm using a cuff for 6 minutes and then released the cuff. This caused a reflex increase in muscle blood flow to the arm, which was partly due to nitric oxide release through the blood vessels. Blood samples taken after the cuff was released showed that nitric oxide levels (as measured by the indirect markers nitrite and nitrate) were highest when GPLC was ingested. We do not know whether an increase in nitric oxide levels promotes muscle growth in bodybuilders.
