Phosphocreatine is a compound stored in muscle; it donates phosphate to ADP and thereby rapidly replenishes ATP during anaerobic muscle contraction. It is synthesized endogenously in the liver from arginine, glycine, and methionine. Dietary sources are milk, steak, and some fish.
(See also Overview of Dietary Supplements Overview of Dietary Supplements Dietary supplements are the most commonly used of all integrative, complementary, and alternative therapies, primarily because they are widely available, relatively inexpensive, and can be bought... read more .)
Claims
Creatine is said to improve physical and athletic performance and to reduce muscle fatigue.
Evidence
Some evidence suggests creatine is effective at increasing work done in a short duration with maximal effort (eg, sprinting, rowing, weightlifting). A small 6-week study in 22 physically active adults also showed creatine ingestion during resistance training sessions may improve muscle strength (1 References Phosphocreatine is a compound stored in muscle; it donates phosphate to ADP and thereby rapidly replenishes ATP during anaerobic muscle contraction. It is synthesized endogenously in the liver... read more ). Creatine has proven therapeutic use in muscle phosphorylase deficiency (glycogen storage disease Glycogen Storage Diseases Glycogen storage diseases are carbohydrate metabolism disorders. There are many numbered and named types, all of which are caused by deficiencies of enzymes involved in glycogen synthesis or... read more type V [McArdle disease]) and gyrate atrophy of the choroid and retina; early data also suggest possible effects in Parkinson disease Parkinson Disease Parkinson disease is a slowly progressive, degenerative disorder characterized by resting tremor, stiffness (rigidity), slow and decreased movement (bradykinesia), and eventually gait and/or... read more and amyotrophic lateral sclerosis Amyotrophic Lateral Sclerosis (ALS) and Other Motor Neuron Diseases (MNDs) Amyotrophic lateral sclerosis and other motor neuron diseases are characterized by steady, relentless, progressive degeneration of corticospinal tracts, anterior horn cells, bulbar motor nuclei... read more .
Numerous clinical trials have demonstrated that creatine supplementation is well tolerated and may increase muscle mass. The effects can be seen in normal healthy people as well as a means of aiding in the treatment of muscle disorders and improving physical function and quality of life in patients with muscle disorders or osteoarthritis Osteoarthritis (OA) Osteoarthritis is a chronic arthropathy characterized by disruption and potential loss of joint cartilage along with other joint changes, including bone hypertrophy (osteophyte formation). Symptoms... read more (2-4 References Phosphocreatine is a compound stored in muscle; it donates phosphate to ADP and thereby rapidly replenishes ATP during anaerobic muscle contraction. It is synthesized endogenously in the liver... read more ).
Adverse Effects
Creatine may cause weight gain (possibly because of an increase in muscle mass) and spurious increases in serum creatinine levels. Minor gastrointestinal symptoms, headache, dehydration, irritability and aggression, edema, electrolyte imbalance, and muscle cramps have been reported anecdotally.
Drug Interactions
No drug interactions are well documented, but taking creatine may increase the risk from drugs, such as nonsteroidal anti-inflammatory drugs (NSAIDs), that affect kidney function. Also, caffeine may decrease the benefit of creatine by decreasing its energy production.
References
1. Mills S, Candow DG, Forbes SC, et al: Effects of creatine supplementation during resistance training sessions in physically active young adults. Nutrients 12(6):1880, 2020. doi:10.3390/nu12061880
2. Kley RA, Tarnopolsky MA, Vorgerd M: Creatine for treating muscle disorders. Cochrane Database Syst Rev (6):CD004760, 2013. doi: 10.1002/14651858.CD004760.pub4
3. Branch JD: Effect of creatine supplementation on body composition and performance: a meta-analysis. Int J Sport Nutr Exerc Metab 13(2):198-226, 2003. doi:10.1123/ijsnem.13.2.198
4. Neves M Jr, Gualano B, Roschel H, et al: Beneficial effect of creatine supplementation in knee osteoarthritis. Med Sci Sports Exerc 43(8):1538-1543, 2011. doi: 10.1249/MSS.0b013e3182118592
More Information
The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
National Institutes of Health (NIH), National Center for Complementary and Integrative Health: Dietary Supplements Marketed for Weight Loss, Bodybuilding, and Sexual Enhancement: What the Science Says
Drugs Mentioned In This Article
Drug Name | Select Trade |
---|---|
arginine |
Arginine, Nutricia SHS L-Arginine, R-Gene |
glycine |
No brand name available |
caffeine |
Cafcit, NoDoz, Stay Awake, Vivarin |