L-carnitine L-tartrate is a popular supplement in some endurance athletes and bodybuilders. L-carnitine is an important chemical found in the mitochondria— the cells’ energy centers— where it helps break down long-chain fatty acids and promotes oxygen consumption. Intense weight training restricts muscle blood flow and oxygen delivery, which interferes with muscle cell function and damages cell membranes.
In young adults, L-carnitine L-tartrate supplements reduced chemical damage to tissues after exercise and promoted muscle tissue repair and recovery. Several studies found that L-carnitine L-tartrate promoted recovery and prevented free radical tissue damage in intensely training young men. A sophisticated study from the University of Connecticut, Storrs, led by Bill Kraemer, found similar results in middle-aged men. Muscle deterioration with age is a serious problem that decreases physical performance, quality of life, and can lead to premature death.
The study showed that L-carnitine L-tartrate reduced markers of tissue breakdown, free radical formation, and muscle soreness after exercise. The supplement had no effect on physical performance. (Metabolism Clinical and Experimental, in press; published online)