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Creatine Supplements for Sports and Fitness

Can Creatine Work for You?


Updated October 01, 2007

Updated October 01, 2007

Origins of Creatine

Vitamin, mineral and natural supplements are popular with people interested in general well-being. Fitness devotees, sportspeople, weight trainers and bodybuilders are heavy users of supplements, often believing that a particular supplement can give them a performance or health advantage.

Supplement taking has many risks associated with it. Is it safe? Does it work? Is it overpriced? How much should I take? Is the product of pharmaceutical grade to ensure safety and efficacy? Can it react adversely with other medications or supplements? Also, small numbers of individuals in any population can have an unusual or abnormal response to any chemical substance they ingest. Absolute safety, in a pharmacological sense, is not a useful concept.

One of the most popular supplements is creatine. Creatine is a naturally occurring substance –- an amino acid –- and it is found in meats and fish. However, most creatine is made in the body by the liver. Creatine should not be confused with “creatinine,” a product of creatine and protein metabolism, an excess of which may indicate poor kidney function.

Creatine is essential for the production of the fundamental energy unit, ATP (adenosine triphosphate). If you don’t produce ATP, the body stops functioning, while deficiencies of creatine production result in decreased muscle function. You can probably see that for athletes and fitness enthusiasts, creatine levels in the body are important.

Manufactured creatine in the form of creatine monohydrate can be absorbed from oral supplements and seems to be treated by the body pretty much like natural creatine.

How Does Creatine Help?

Fuel for muscles
Maximizing the muscle stores of creatine seems to enhance the performance of the short, high-intensity energy system called the ATP and phosphocreatine system, which is used in shorter exercise bouts up to about 20 seconds. Supplemental creatine may provide a reservoir of creatine that is available for replenishing ATP during repeated short training intervals. Weight lifting repetitions and sets mostly fit into this category.

In fact, most studies show that creatine is most effective for exercise bouts or events that last less than 30 seconds. Diminished benefits may be available in exercise lasting from 30 seconds to 3 minutes.

Strength and bulk development
Second, creatine may bulk up muscle size and improve strength. Water accumulation in muscle appears to account for some of this bulk and weight gain. Clearly this is of great interest to bodybuilders and strength trainers, but creatine has also been found to improve muscle function in the elderly and in individuals suffering from certain muscle diseases.

Combining the attributes of size and strength with increased athletic power has made creatine a hot supplement for power sports such as football, baseball, track and field, the big men in basketball and anything else where speed and strength are advantageous.

Creatine has most proven benefits for explosive events like sprinting, jumping and weight lifting. Much of these benefits may result from creatine supplementation providing the capacity to train harder and more often. Creatine has not shown to be beneficial for less intense endurance sports such as marathon running or cycle road racing.

Will it work for you?
It’s important to know that not everyone responds to creatine supplementation. Some sports medicine authorities have estimated that 30% of users see no beneficial effect.

Is Creatine Safe?

Kidney and liver toxicity
In the last 10 years, creatine has been used extensively, even if mostly by men, and studied substantially, if not comprehensively. Few side effects have been consistently reported from short-term use with approved quantities. The likelihood of it being a health hazard for long-time, regular users of creatine is still unknown. Kidney and liver function in creatine users has been studied as a potential target of toxicity, but no consequential effects have been shown to occur at recommended doses in controlled trials. However, case reports and animal studies suggest possible adverse effects on the kidney.

In one Dutch study with 175 subjects, half were given 10 grams of creatine each day and the other half, randomly selected, were given a dummy supplement with no creatine for 310 days. No kidney or liver abnormalities were detected.

It would be sensible not to take creatine if kidney disease is present or suspected. Some overweight people have chronic, undiagnosed kidney disease, so using creatine in a weight loss or bodybuilding program would probably be unwise for these people.

Muscle cramps, water retention and swollen limbs
In the same Dutch study, swollen limbs were seen more often in the creatine takers, and three individuals in the creatine group had to withdraw because of nausea. The swollen limbs were attributed to water retention, which is one effect that seems to be established both scientifically and by word of mouth among users. Whether this is an adverse effect is probably best left to each individual's assessment. In another sense it may reflect muscle enlargement (hypertrophy), or more seriously, muscle compartment abnormality.

Muscle compartment syndrome is a condition which often affects the lower legs although other areas of the body can be affected. The muscles swell and fill the "compartment" in which they function, producing abnormal pressure that can result in pain and, at worst, damage to nerves and small blood vessels.

Complaints of muscle cramping seem to be widespread, if not epidemic, in the athletic, sports and weight training communities and this may be as a result of excessive water retention and muscle swelling at higher “loading” doses. These high "starter" doses are not necessary as you will see in the following discussion on how much to take.

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