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Chris Pagnani Curling
What is Creatine Monohydrate?
Creatine Monohydrate (Cr) is a substance that is found naturally in the human body. Without supplementation, the typical 150-pound individual maintains a level of about 120 grams at any given time (www.bodybuildingforyou.com/creatine/creatine-monohydrate.htm). The human body uses about 2 grams of Cr per day with minimal physical activity. Increased physical activity calls for a higher utilization of this substance (Persky & Brazeau, 2001). Creatine is synthesized in the liver, kidneys and pancreas. One’s Cr level is also maintained through diet (red meat and fish). It is stored in muscle fibers (95%), in addition to the brain, liver, kidneys and testes (Persky et. al., 2001). Creatine is involved in ATP synthesis in muscular tissue, the pH balance of muscular tissue and membrane stabilization (Persky et.al., 2001). Thus, it has been attributed to increases in muscular force and power, the reduction of muscular fatigue, and an increase in muscle mass when coupled with resistance training (Persky et.al., 2001). Athletes, bodybuilders, and individuals with muscular disorders have begun to supplement their diet with additional Cr. Over 200 million dollars each year are spent on Cr supplements in the United States (Persky et.al., 2001).
How Does Creatine Work?
According to Pharmacological Reviews, with the aid of Creatine Kinase, Cr and ATP (adenosine triphosphate) couple to form Creatine Phosphate and ADP (adenosine diphosphate). “The formation of the polar PCr locks Cr in the muscle and maintains the retention of Cr because the charge prevents partitioning through biological membranes” (pg. 164). During exercise ADP can undergo a phosphorylation reaction to produce ATP and Cr. This occurs when the pH of muscular tissue becomes acidic, due to the presence of lactic acid. Lactic acid build-up is the result of strenuous exercise, during times of ATP exhaustion. Thus, Cr serves as both a source of ATP (which powers the muscles) and a pH buffer as well. This extra ATP can be used to prolong workout sessions. In addition, due to its ability to raise muscular pH, Cr has a dampening effect on muscle soreness (a product of lactic acid build-up), and decreases muscular recovery periods from resistance training.
Research suggests that the levels of Creatine and Creatine Phosphate in muscular tissue can be increased (as well as their effects), with Cr supplementation (Guerrero-Ontiveros & Wallimann, 1998). In double blind clinical studies, supplementation has been shown to significantly increase one’s fat-free mass, and muscular strength (Brose, Parise, & Tarnopolsky, 2003; Watsford, Murphy, & Spinks, 2003). In a study completed by Volek (as cited by Persky and Brazeau, 2001, pg.165), “Cr supplementation increased muscle fiber diameter in both Type 1 and Type 2 muscle fibers by 35%. Resistance trained subjects not supplemented with Cr had fiber-type increases of 6 to 15%.” This increase in muscle size can be attributed to an increase in protein synthesis, or a reduction of protein catabolism (Persky et.al., 2001). In addition to athletes, research has suggested that individuals with Parkinson’s Disease, Huntington’s Disease, Duchenne’s Muscular Dystrophy, and other muscular disorders could benefit from supplemental use (Persky et.al., 2001).
What’s the Problem?
Creatine Monohydrate supplementation has been accused of causing nausea, diarrhea, dizziness, weakness, muscle cramping, stomach ache, increased urination, kidney damage, kidney stones, anxiety attacks, irritability, depression, heart failure, muscle tears and other potentially dangerous side effects, by users and the public (www.stow.summit.k12.oh.us/cshp_creatine.htm). Derek Bell, a Houston Astros outfielder, attributes his two hospitalizations in one year (for severe kidney problems) to Cr use (www.lougehrigsdisease.net/als_pages/creatine.htm). In addition, the death of Jeffrey Reese, an ex-Michigan State Wrestler, has been attributed to the use of Cr coupled with weight loss (www.stow.summit.k12.oh.us/cshp_creatine.htm).
What Does Research Tell Us?
The most prominent and serious criticisms of Creatine Monohydrate supplementation are renal and hepatic dysfunction, and an increased risk of muscle tear. In a study involving long-term Cr users (10 months to 5 years), the renal (kidney) functions of glomerular filtration rate, tubular reabsorption, and glomerular membrane permeability were found to be normal for Creatine users (Poortmans, & Francaux, 1999). According to a double-blind clinical study by Kamber (as cited by Persky, & Brazeau, 2001), Cr use does not have an effect on renal or hepatic enzymes and function. Studies also have suggested that Cr use does not affect muscle stiffness, which can contribute to muscle tears (Watsford, Murphy, & Spinks, 2003). Regarding the other criticisms of Cr use, clinical studies suggesting that supplemental use is correlated with gastrointestinal dysfunction, nausea, dizziness, weakness, muscle cramping, kidney stones, anxiety attacks, irritability, depression and heart failure is non-existent. However, research on Cr use is mostly short term (no studies have been completed of individuals who have used Creatine for over 6 years), and limited.
One should keep in mind, that although studies have suggested that Creatine Monohydrate supplementation does not have detrimental side effects, many Creatine supplements contain additional ingredients. For example, Cell-Tech (a supplement made by Muscle-Tech) contains alpha lipoic acid, which is meant to increase muscular tissue uptake of Cr (www.muscletech.com). The warning label for this product reads:
Due to the pH (acidity) of alpha lipoic acid, users may experience a slight burning sensation in their throat while consuming Cell-Tech…Do not use if you suffer from diabetes or if you are prone to hyperglycemia and/or hypoglycemia. Since Cell-Tech stimulates insulin production and Creatine delivery so rapidly, some individuals may be susceptible to diarrhea, nausea, tiredness, or extreme thirst…If symptoms of sweating, nervousness, trembling, faintness, palpitation, skin rash or hunger occur, discontinue product and consult a physician.
Creatine Monohydrate is a substance that naturally exists in the body. Due to its anabolic effects on muscular tissue, and ability to relieve muscle soreness, athletes and individuals with muscular disorders have begun to supplement their diet with Creatine. There have been many accusations regarding the negative side effects of this practice, but studies to date have suggested that these accusations are unfounded. However, these studies are limited in number, and scope of research. There are also no studies that take into consideration long-term effects (Cr use over six years). In addition, before using a Creatine supplement, one should take into consideration the other ingredients that are used; they could be potentially dangerous as well.
Brose, A., Parise, G., & Tarnopolsky, M.A. (2003). Creatine supplementation enhances
Isometric strength and body composition improvements following strength
Exercise training in older adults. The Journals of Gerontology, 58 (1) pgs. 11-20.
Guerrero-Ontiveros, M.L., & Wallimann, T. (1998). Creatine supplementation in health
And disease. Effects of chronic creatine ingestion in vivo: down regulation
Of the expression of creatine transporter isoforms in skeletal muscle. Molecular
Cell Biochemistry, 184 (1-2) pgs. 427-437.
Persky, Adam M., & Brazeau, Gayle A. (2001). Clinical pharmacology of the dietary
supplement creatine monohydrate. Pharmacological Review, 53 (2) pgs. 161-176.
Poortmans, J.R., Francaux, M. (1999). Long-term creatine supplementation does not
Impair renal function in healthy athletes. Medical Sciences Sports Exercise,
31 (8) pgs. 1108-1110.
Watsford, M.L., Murphy, A.J., & Spinks. (2003). Creatine supplementation and its
effect on musculotendinous stiffness and performance. Journal of Strength
and Conditioning Research / National Strength & Conditioning Association,
17 (1) pgs. 26-33.
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