Creatine Case Study

Case Study

History

Learning Goals /
Concept Map


Creatine and Related Compounds

Structure

Amino Acids

Creatine in the Body

Equilibrium

Creatine-Creatinine Equilibrium

Creatinine Test for Kidney Function

Detection

Regulation and Ethics

Amine & Nitrile Chemistry

Laboratory Synthesis

Chemical Analysis

Creatine-Phosphocreatine Equilibrium

Uses & Side Effects


Creatine & Related Compounds

What is Creatine?
Creatine is a natural substance found in the human body that is fundamental to energy metabolism and muscle contraction.  Creatine is synthesized naturally in the liver, pancreas, and kidneys from three amino acids:  glycine, arginine, and methionine.[1,2]  Learn more about AMINO ACIDS.

Creatine can also be obtained from dietary supplements and certain foods, such as beef, chicken and fish.[2]  See other food sources in CREATINE IN THE BODY.  Approximately 95% of creatine in the body is found in skeletal muscle, while the other 5% is distributed throughout the heart, brain, testes, and retina.[2,3]  Creatine exists in two different forms within skeletal muscle:  as free, chemically-unbound creatine and as creatine phosphate.  Creatine phosphate, also known as phosphocreatine, makes up two-thirds of the creatine levels in skeletal muscle tissue, while the remaining one-third exists as free creatine.[3]  Read more about the CREATINE-PHOSPHOCREATINE EQUILIBRIUM.

In the body creatine is broken down into creatinine, which is excreted in the urine.  The conversion of creatine into creatinine is irreversible and increases slightly during intense physical exercise.  In the event of kidney disease, however, there can be as much as a 10-fold increase in urinary creatinine levels, making this a useful indicator of kidney disease.[4]  Read more about the CREATINE-CREATININE EQUILIBRIUM, and the CREATININE TEST FOR KIDNEY FUNCTION.

Creatine provides the energy necessary for vigorous muscle contraction, such as the muscle actions involved in most athletic activities.  Consequently, creatine is currently in demand by athletes as a performance enhancer.  At present, creatine is not regulated by the FDA or banned by the National Collegiate Athletic Association or the International Olympic Committee.[6,7,8]  In fact, athletes in the former USSR and Bulgaria are thought to have been supplementing with creatine to enhance athletic performance as early as the 1970s.  Similarly, British sprinters and hurdlers have credited their athletic success in the early 1990s with creatine supplementation.[9]  Creatine supplements have been especially popular with bodybuilders, wrestlers, cyclists, tennis players, distance runners, rowers, skiers, football players, basketball players, rugby players, and ice hockey players[9] at all levels of competition—including high school, college, professional, and Olympic athletes.

Find out more about the DISCOVERY AND HISTORY OF CREATINE.

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[1] Clark, Joseph F. “Creatine and Phosphocreatine: A Review of Their Use in Exercise and Sport.” Journal of Athletic Training. 1997, 32(1), 45-50.
[2] Juhn, Mark S. “Oral Creatine Supplementation: Separating Fact from Hype.” The Physician and Sports Medicine. 1999, 27(5).
[3] Balsom, Paul D; Soderlund, Karin; Ekblom, Bjorn.  “Creatine in Humans with Special Reference to Creatine Supplementation.”  Sports Medicine. 1994, 18, 268-280.
[4] Williams, Melvin H.; Kreider, Richard B.; Branch, J. David. Creatine: The Power Supplement, Human Kinetics: Champaign, IL, 1999.
[5] Graham, Angie S.; Hatton, Randy C.  “Creatine Studies.” Journal of the American Pharmaceutical Association. 1999, 39(6), 803-810.
[6]NCAA Drug Testing Program. National Collegiate Athletic Association. <http://www.ncaa.org/wps/ncaa?ContentID=282> (accessed April 2009)
[7] Sydney Olympics: Banned Drugs. Guardian News and Media Limited 2008. <http://www.guardian.co.uk/flash/0,5860,366056,00.html> (accessed April 2009).
[8] Prohibited List. World Anti-Doping Agency. <http://www.wada-ama.org/en/prohibitedlist.ch2> (accessed April 2009).
[9] Wyss, Markus; Kaddurah-Daouk, Rima. “Creatine and Creatinine Metabolism.” Physiological Reviews. 2000, 80, 1107-1213. <http://physrev.physiology.org/cgi/content/full/80/3/1107> (accessed April 2009).