The NCAA Committee on Competitive Safeguards and Medical Aspects of Sports (CSMAS) continues to monitor the effect on sport performance and potential injury related to the ingestion of creatine monohydrate. Creatine is not on the NCAA list of banned substances but is one of the most widely used supplements by athletes on the market today. Athletes of all ages and gender report using creatine monohydrate.

Creatine monohydrate is an amino acid that is synthesized from arginine and glycine in the liver, kidneys and pancreas. It also is available in the diet from meats and fish.

Nearly all of the total body creatine is contained in skeletal muscle, of which about one-third is free creatine and two-thirds is in the phosphorylated form, phosphocreatine. Creatine synthesized by the body is adequate to maintain normal levels in individuals on a creatine-free diet; vegetarians are reported to have slightly lower concentrations of creatine compared to individuals who consume meat daily.

The primary function of creatine is to act as a buffer against rapid increase in energy requirements. Phosphocreatine helps replenish adenosine triphosphate (ATP) during short bursts of high-intensity exercise. Depletion of phosphocreatine is related to the onset of fatigue during heavy exercise. Thus, some have theorized that increasing creatine in muscle via supplementation may have a positive effect on high-intensity exercise performance by prolonging the availability of a very powerful (ATP-CP and anaerobic glycolysis energy system) but low capacity energy system.

Research shows that creatine supplementation for less than one week results in significant increases in total creatine content of skeletal muscle. Increases in total creatine are a result of an increase in both creatine and phosphocreatine (phosphocreatine representing 20 to 60 percent of the increase).

Creatine supplementation increases the bioavailability of phosphocreatine in skeletal muscle cells. This increase is thought to enhance muscle performance in two ways. First, more available phosphocreatine allows faster resynthesis of ATP to provide energy for brief, high intensity exercise, like sprinting, jumping or weight lifting. Second, phosphocreatine buffers the intracellular hydrogen ions associated with lactate production and muscle fatigue during exercise.

When high doses of creatine are ingested over a period of four to six days, the muscle creatine content will remain elevated for several weeks. The mechanism by which creatine supplementation might improve performance is not entirely understood, although it does seem clear that this effect is related to the increased muscle phosphocreatine content. The most significant effect that creatine supplementation has had in research regards body weight. Most studies report increases in body weight of up to six pounds after one week of supplementation.

Creatine supplementation studies consistently demonstrate increased muscle mass and strength gains. Some research suggest that not all individuals will respond the same to creatine supplementation with further evidence suggesting that gender plays a significant role in this response.

Recent research indicates that the rate of phosphocreatine resynthesis after intense exercise is enhanced after high-dose creatine supplementation. This allows faster recovery after short-term, high-intensity exercise, especially in repeated bouts of exercise. Most studies having significant contributions to enhanced sport performance were studies that used protocols requiring the short-term energy systems, ATP-CP and anaerobic glycolysis. The results suggest that activities most likely to benefit from creatine supplementation are multiple bouts of high-intensity efforts that lasted from approximately eight to 12 seconds.

Studies that examined enhanced aerobic capacity indicated little to no change in aerobic performance. Research examining changes in renal function, insulin levels, heart rate response, sweat rate response and blood pressure found no significant changes while ingesting creatine.

To date there is no direct cause-and-effect relationship between creatine ingestion and negative side effects in scientific literature. Some studies reported no differences in the incidence of muscle injury, cramps or other side effects, suggesting that long-term creatine supplementation does not result in adverse health effects. Others reported no changes in heart-rate response, blood pressure and sweat rate response while ingesting creatine. All articles relating to the ingestion of creatine monohydrate agreed that further research was needed in the area of long-term use.