The human body uses L-carnitine slightly differently than other amino acids. Although L-carnitine is synthesized in the liver and kidneys from lysine and methionine and used in protein synthesis and as a neurotransmitter, it also transports fatty acids to cellular mitochondria. L-carnitine therefore converts fat into energy and that is why it is informally referred to as “muscle energy”. Due to its important role in fat metabolism, it is believed that it significantly supports fat burning and weight loss. Fat, which has twice as many calories as protein or carbohydrates, can be used as a source of energy during any type of physical activity and at any level of advancement. This, in turn, creates ideal conditions for obtaining better results and stimulating the growth of dry muscle mass. In addition to the fact that L-carnitine contributes to a healthy body composition, reducing the level of glycogen and lactic acid in the muscles can also delay the appearance of fatigue and, consequently, increase endurance.