Fact Sheet: on the use of Creatine

What is Creatine? Creatine is a naturally occurring compound found primarily in meats/fish. Various body organs also manufacture it. Creatine plays an important role in energy metabolism within muscle tissue. Creatine supplements are made in laboratories and vary widely in purity. Creatine is sold in many forms but creatine monohydrate is the form the body is best able to absorb.

How does Creatine work? The fuel source for all muscle contractions is ATP(adenosine triphosphate). During exercise, enzymes in the body split off one of the phosphates from the ATP molecule and this releases the energy needed to fuel muscle contraction. As a by-product of this process the ATP molecule is transformed into ADP(adenosine diphosphate). Unfortunately, the body only stores enough ATP to permit 8-12 seconds of work and the body is unable to use ADP to generate energy. To continue working beyond this 8-12 second limit, the body must re-synthesis ATP and this is where creatine plays its role. In the body, creatine is attached to a phosphate molecule to form phosphocreatine. When ATP is broken down into ADP, phosphocreatine delivers a phosphate molecule to ADP to produce another ATP molecule. This rejuvenated ATP molecule can once again be used to fuel more muscle contractions.

Does Creatine supplementation work? The research shows that creatine supplementation can improve your ability to perform bursts of high intensity exercise lasting from 1-2 minutes in duration. The benefits from using creatine vary from one person to the next. How much you benefit from using creatine depends on how much creatine your own body produces. People who are low creatine producers should benefit more from taking a creatine supplement than people who are high creatine producers. It is important to note that the body can only store a limited amount of creatine and anything more than this is expelled in your urine. Taking more than the recommended dosage of creatine will not give you any training benefit but it will give you very expensive urine.

Why take Creatine? If part of your fitness program involves short duration high intensity exercise such as weight lifting, power lifting, sprinting, etc. then using a creatine supplement may help you to train harder and longer. Creatine may also allow you to recover faster between bouts of very intense short duration exercise. All of these things could combine to help you to train more effectively and so make greater fitness gains. Creatine offers no training benefits to athletes who compete in endurance events and in fact may hinder their performance.

Does Creatine build muscle? Creatine by itself will not build muscle. Creatine simply allows you to perform high intensity exercise for longer periods and to recover slightly faster. It is this increased ability to train, that can stimulate muscle growth. Everyone who uses creatine will experience some weight gain in the first 7-10 days of use. Don't be fooled, this gain is the result of water retention not muscle growth.

Are there side effects from Creatine use? Researchers have not demonstrated any significant side effects from the use of creatine supplements. The minor side effects include such things as abdominal cramping, nausea, diarrhea, sleep problems, muscle cramping and muscle tightness. Since creatine is cleared from the body via the kidney, people with kidney problems should be assessed by their physician before taking this product. No one knows if the long-term use of creatine supplements is potentially harmful

How should it be taken? Soldiers who choose to use creatine can take it in one of two ways. The first involves taking a loading dose of 20 grams a day for 5 days to rapidly saturate your creatine stores. Once this saturation occurs, your body continues to discard a small volume of creatine on a daily basis and to make up for these losses you require only 2-3 grams of creatine/day. In the second, you simply begin by taking 2-3 grams of creatine/day and build your stores up more gradually. Recent evidence suggests that the body is better able to absorb creatine, if it is taken with a sugar containing drink. The companies selling creatine recommend a cycle of 4-5 weeks of creatine use followed by a week off of the product before the cycle is repeated. Experts in the field of creatine supplementation feel this "cycling" is not necessary.

Contamination? Dietary supplements are considered foods rather than drugs and so are not subject to strict manufacturing controls. Without this regulatory protection, the contents of many of these products have been shown to be very different from what is listed on their labels. Some supplements have been shown to contain near toxic levels of certain ingredients, others do not contain the ingredients they claim to have and others contain items that are not listed on their labels. Some of these "extras" include things such as anabolic steroids, ephedrine and other substances that have been banned by the International Olympic Committee. The unwanted extras may also include such things as lead, broken glass and animal feces. Unfortunately, it is impossible for a consumer to know what is truly in any of these products and this could be a problem for athletes who must undergo drug testing.

The Bottom Line! For people with low muscle creatine stores who participate in sports that require repetitive high intensity short duration activities - creatine may be helpful in training and competition.

D. Menard MD, Dip Sport Med
Sport Medicine Consultant
DCOS Force Health Protection