Creatine and Weight Lifters

The following is a brief guide to supplementing with the ergogenic aid creatine.

Creatine is a natural substance made by the body, found mostly in muscle tissue. Because of its role in energy generation and exercise recovery, it has become popular as a sports supplement - or ergogenic aid - particularly among those who wish to increase strength, endurance, and lean body mass.

What & Why

The following are the natural functions and activities of creatine, and how they may be particularly attractive to athletes:

• Energy: Creatine is a "back-up" source of energy production in the muscles, supporting quick bursts (about 10 seconds' worth) of high-intensity activity, as in power-lifting, sprinting, and volleys.
• Volumising: Creatine pulls water into muscle tissues, increasing their size, and enhancing a "pumped up" look.
• Lactic Acid Buffer: High-intensity exercise often causes a burning sensation in muscles, a sign of lactic acid build-up. Creatine has been shown to delay this process.
• Protein Synthesis: Creatine may promote building of muscle mass by driving the use of dietary protein by muscle tissues during resistance training.
• Antioxidant: Creatine has been suggested in laboratory research to possess antioxidant capabilities, acting against free radicals naturally generated during exercise.

Several studies have been conducted based on the above properties to see if supplements could improve the performance of various sports activities. While these were not considered of adequate power or quality to draw firm conclusions, most yielded at least mild benefits.

Supplemental Sources

Creatine is available in foods, specifically meat and fish; the typical diet provides about two grams per day. As a supplement, it is available in powder, capsule, tablet, bar, chewable gum or liquid form. The following should be considered during selection, and clearly labeled on the product container:

• Purity: Many creatine products use the 'Creapure' brand, made according to specific standards that limit the degree of contamination. Whether or not this source is used, product labels should list purity assay results, and/or provide contact information for requesting them.
• Additives: In addition to fillers and binders, some creatine products contain sweeteners and dyes. Note that the more additives there are, the less actual creatine will be available per dose.
• Carriers: Carriers are chemical compounds that enable creatine to more effectively be absorbed or utilised by the body. Unfortunately, not all forms are created equal or even supported in the research. The most widely available - creatine monohydrate - is comprised of 88% creatine and 12% water, meaning that for every 5 grams of powder, 4.4 grams is pure creatine.
• The following additional product information should be provided on the label:
  • Batch and/or lot number (to be used when contacting the manufacturer)
  • Expiration date
  • Safe dosing

Recommended Regimens

Most traditional creatine programs are based on the following, believed to increase muscle creatine by an average of 20%:

• Begin with five days of "loading," at a daily dose of 15-20 grams (depending on body weight)
• Following the initial load, the daily dose is reduced to 10 grams

However, recent data have suggested that such high amounts may be unnecessary, showing results with the following:

• Loading of 10-30 grams per day for the first week (depending on body weight)
• 2-5 grams per day as maintenance

While the reliability of the degree of increase is not known, it has been confirmed that muscle has a saturation limit. This means that increasing intake of creatine will not result in increased storage, rather in excretion of the excess. For this reason as well, the benefits of continued supplementation beyond one month have not been consistently observed. The following is therefore recommended for long-term use, assuming regular physical training:

• Five weeks on (a combination of loading and maintenance as described above)
• A minimum of four weeks off (a "wash-out" phase, during which the extra creatine is naturally depleted from muscle tissue)

While the loading phase is not essential, it has been observed to shorten the time to results by 50%.

Safety

No serious side effects have been reported in healthy people who follow the traditionally recommended dosing guidelines for creatine supplementation. However, the following should be noted:

• Because excess creatine is converted to creatinine - a natural but toxic byproduct - and released through the kidneys, some experts are concerned that high doses could cause kidney damage.
• Primary side effects associated with creatine supplementation have been reported to be gastrointestinal distress - including gas, bloating, and diarrhea - and muscle cramping, possibly due to increased water retention (see Volumizing above).
• No long-term studies on creatine supplementation in humans have been conducted, and risks associated with extended use in laboratory animals have thus far been observed only at a very basic level.