Creatinol-O-Phosphate (Creatinolfosfate, creatinol phosphate, COP) is a cardioprotective drug and structural analog of creatine, not to be confused with phosphocreatine (a phosphorylated creatine molecule). Its full molecular name is N-methyl-N-(beta-hydroxyethyl)guanidine O-phosphate  and may serve as source of creatine.
Creatinol O-phosphate and its uses in bodybuilding supplements
In theory on the inside of a cell, creatinol-o-phosphate loses its attached phosphate which is used to form the high-energy molecule, ATP (Adenosine Triphosphate), which can be used as energy for muscle contraction.  According to this, creatinol o-phosphate contributes to production of ATP molecules.
There is a lack of clinical studies conducted with creatinol-o-phosphate that assess its benefits on exercise performance. Despite the fact, it is present in many supplements available today. We managed to find one article on bodybuilding.com  which enthusiastically applauses its use. The article summarizes a few italian studies which we didn’t manage to find online but even if we did only google translate could help us. It is noted in the article that once muscle cells are saturated, the primary action of creatinol o-phosphate is to prolong anaerobic glycolysis in the presence of excess lactic acid. Creatinol o-phosphate is said to override the mechanism of excess lactic acid accumulation by acting as an intracellular buffer, preventing a dramatic drop in pH and allowing muscle contractions to continue beyond the point at which your body would normally shut down activity.
It is also written that in a study by R. De Gasperi a dramatic increase in time under tension threshold was noted after seven days.
Safety and side effects of creatinol O-phosphate
Creatinol-o-phosphate is distributed in all organs, particularly in liver and kidney where it is being dephosphorylated and eliminated with urine. According to Morazi and Ghirardi  : “Toxicological studies confirm that creatinol o-phosphate has no side effects, is excellently tolerated.”
- Godfraind, T., and M. M. Saleh. “Action of creatinol-O-phosphate on the contractility changes evoked by hypoxia and ischemia in rat isolated heart.” Arzneimittel-Forschung 34.9 (1984): 968.
- Lodish, Harvey, et al. “Molecular cell biology.” New York (2000).
- Emerging from stacks of cutting-edge clinical research are two powerful muscle-and strength-enhancing compounds: Creatinol-O-Phosphate & Beta-Alanine. Retrieved from bodybuilding.com at 25. April 2013
- Marzo, A., and P. Ghirardi. “Pharmacological and toxicological properties of creatinol O-phosphate. A review.” Arzneimittel-Forschung 29.9a (1979): 1449.