t undergo a chemical process to form Creatine. Creatine is manufactured in the liver and may be produced in the pancreas and kidneys. It is transported through the blood and taken up by muscle cell, where it is converted into Creatine phosphate; also called phosphocreatine. This reaction involves the enzyme Creatine kinase that helps bond Creatine to a high-energy phosphate group. Once Creatine is bound to a phosphate group, it is permanently stored in a cell as phosphocreatine until it is used to produce chemical energy called Adenosine Triphosphate (ATP). ATP then loses a phosphate group and becomes Adenosine Diphosphate (ADP). Creatine, when present in the muscle in sufficient amounts donates a phosphate group to ADP and it rapidly retransform to ATP, which is immediately available to the muscle to be used for a fuel for exercise. During brief explosive-type exercises, the energy supplied to rephosphorylate adenosine diphosphate (ADP) to adenosine triphosphate (ATP) is determined largely by the amount of phosphocreatine stored in the muscle. As phosphocreatine stores become depleted, performance is likely to rapidly deteriorate, due to the inability to resynthesize ATP at the rate required. "Since the availability of phosphocreatine stores in the muscle may significantly influence the amount of energy generated during brief periods of high intensity exercise, it has been hypothesized that increasing muscle creatine through creatine supplementation may increase the availability of phosphocreatine and allow for an accelerated rate of resynthesis of ATP during and following high intensity, short duration exercises(Kreider 1)." ATP is the primary source of fuel for muscular exercise. It is used before sugars (carbohydrates) and before fats. When muscles are used to lift weight, run or perform any type of work the ATP is broken down to ADP (adenosine diphosphate) and energy is released. The amount of ATP stored in the muscles will only fu...
