Creatine is a man made form of a chemical that is normally found in the body. It is also found in meat and fish. Most Creatine in the human body is stored in the muscles. Creatine is a source of energy for muscle contraction and is also involved in muscle growth.
Creatine is a naturally occurring non-protein amino acid of which the primary metabolic role is to combine Creatine with a Phosphoryl group to generate Phosphocreatine, which is used to regenerate ATP or Adenosine Triphosphate.