Creatine Phosphate Complex and Creatine Serum - Medicinal Properties in Whole Foods

Townsend Letter for Doctors and Patients,  Feb-March, 2003  by Gina L. Nick

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Effectively Administering a Key Component of the ATP Energy Cycle in its Natural Form; in Physiologic Rather than Pharmacological Doses, for Optimal Athletic Performance.

Creatine has recently achieved immense popularity among fitness enthusiasts because of its intimate role in the production of adenosine triphosphate (ATP). The current directions in research are two-fold: 1) to determine more precisely the effective applications of creatine's ergogenic effect and 2) to devise the most physiologic form of creatine for supplementation. The weight of experimental evidence supports a benefit from creatine supplements for repetitive, brief, maximum muscle efforts. Though brief, this may lead to a significant training and performance advantage. I have recently come across a safe, easy to take, water soluble formulation of creatine that combines the most natural salt, creatine phosphate (the one directly used by the muscle to regenerate ATP), with stability both on the shelf and in the body, resistance to hydrolysis, transmucosal absorption, and 100% bionvailability in a highly tolerable oral vehicle. Most importantly, this formulation was developed using physiologic doses, rather t han popular pharmacological doses of its insoluble form, creatine monohydrate. Again, the aim of this column is to elucidate the value inherent in using key tertiary functional components, as they naturally occur, for maximum physiologic benefit. The supplemental use of Creatine Phosphate Complex and Creatine Serum supports this assertion, as it is delivered in doses naturally found in whole foods.

Whole Food Sources of Creatine

Whole food sources of creatine include beef, fish, pork and even cranberries. Figure 1 [Balsom 1994] elucidates the low levels of creatine found in whole foods. Please note that in each case, levels do not exceed 3 grams. However, the sports supplement industry has advocated the use of 20+ grams of the amino acid per day, in its most insoluble form (creatine monohydrate).

Mechanism of action

A brief review of creatine's contribution to ATP production is in order. ATP is the muscle's single source of energy ATP, in the presence of Ca++ released into mucscle cytosol from the sarcoplasmic reticulum by motor nerve impulses, causes a stereochemical change in the configuration of myosin, allowing it to "climb" the intervening actin fibrils. In the process, myosin, an ATPase, dephosphorylates ATP. Muscle contraction results. Altogether a muscle can increase its ATP utilization several hundred-fold during high intensity exercise. [Balsom 1994] Four phases ofATP activity occur in a stepwise fashion as muscles begin work.

* The first phase is a rapid dephosphorylation of the ATP existing in the muscle cytosol. At maximum or near maximum exertion existing ATP is depleted rapidly.

* The second phase is an anaerobic regeneration of ATP accomplished in muscle by cytosolic creatine kinase (CK) rephosphorylating the ADP from creatine phosphate (PCr). CK transfers a phosphate group from PCr to ADP according to the following reaction:

CK

PCr + ADP + [H.sup.+] -- ATP + creatine

This second phase, the alactic anaerobic phase, depletes PCr stores within 20 seconds in Type II (fast twitch) fibers, where creatine is more abundant than in Type I (slow twitch) fibers. [Juhn 1998]

* The third phase rephysphorylates ADP by anaerobic glycolysis, wherein glucose is converted to lactic acid. Decreasing stores of PCr signal an increase in glycolysis. [Storey 1974]

* The fourth phase is the aerobic conversion of lactate to pyruvate and subsequent entry into the citric acid cycle, where ATP is restored in mitochondria in the presence of oxygen.

These phases do not follow each other sequentially but rather additively, the glycolytic pathway being maximally operative within one second of maximum muscle contraction. [Hultman 1991) Sustained aerobic exertion is possible when the sum of the first, second and fourth phases (stimulated to maximum conditioned levels of activity) produce sufficient ATP without an accumulation of lactic acid by the third phase. Lactic acid buildup, representing the oxygen deficit, is a principle cause of muscle fatigue.

Note that in the second phase a proton is taken up, a buffering action that helps to compensate for the buildup of lactic acid. This second phase is reversible in the mitochondria. In the presence of oxygen, an isoform of CK in the mitochondrium transfers a phosphate group from regenerated ATP to creatine. The resulting PCr "shuttles" energy back to the muscle cytosol in preparation for the next round of muscle contractions. This effect has been termed a "spatial energy buffer," utilizing creatine/PCr to improve the efficiency of ATP synthesis and utilization. [Incledon 2002, Juhn 1998, Bessman 1985, Bessman 1981] It is the second or alactic anaerobic phase where creatine plays its most important role.

"The rate of anaerobic glycolysis is regulated in particular by allosteric enzymes, such as phosphofructokinase; one of the inhibitors of the process is the level of PCr. When this falls, anaerobic glycolysis gradually starts. Consequently, an increase in intramuscular PCr provides "protection" from the premature onset of anaerobic glycolysis." [French Report]