Sorry DU mods, 5 paragraphs rather than 4 but I don;t think anyone will care. . .
http://www.bodybuilding.com/fun/koch1.htm<snip>
Creatine attracts water, so as your muscles absorb and store creatine, it brings additional water with it. This process super-saturates the muscle tissue with water and creatine, thus enlarging the actual muscle tissue. This super-saturation results in your muscles having that "just trained feeling" all day long. Many refer to this as the "perpetual pump" from creatine. Larger muscles in a matter of days: Can you believe some people refer to this phenomenon as a "side effect" of creatine? Indeed, many people take creatine for this "side effect" alone!
When you first start to take this supplement, it is common to gain a few pounds of muscle. Typical gains are three to five pounds, up to ten being possible, all in a week to ten days - thanks to this super-saturation. The additional weight gain in your muscles is good news, because every extra pound of functional muscle means you will burn additional calories…even while you are resting.
Make no mistake. Even though some of the weight increase is water in your muscles, it still acts as functional muscle. Some creatine opponents have gone on record stating that it just causes your muscles to retain water and is of no real value. Let's put things in perspective. Your muscles are already about 70 percent water without creatine. So is that seventy percent of your muscle useless to begin with? I don't think so. If you suck the water out of your muscles, you are left with a wrinkly little corpse.
But the question remains, are the gains you receive only muscular water retention, or are they actually lean muscle? According to a study done on a bunch of little piggies at Texas A & M University, the gain is lean muscle.(9) Before they were slaughtered, some pigs were fed 25g of creatine for five days, while the other little piggies got none. The pigs that were fed creatine gained almost five pounds more than the ones that did not receive creatine. When cooked, the muscle-bound little pigs that fed creatine showed less meat loss than the pigs not fed creatine. Bacon, anyone? So what can we learn from our squeaky little friends (besides how much fun rolling around naked in mud is, of course)?
From this study, one can conclude that while creatine results in inter-muscular water retention, it may also increase lean muscle. In yet another Belgium study, 25 healthy males were placed on a 42-day controlled strength-training program. Eight were fed creatine, ten a placebo, and seven formed a control group. The body mass of the creatine group went up two kilograms, while the other two groups showed no increase. The researchers concluded that "the relative volumes of the body water compartments remained constant and therefore the gain in body mass cannot be attributed to water retention, but probably to dry matter growth accompanied with a normal water volume." (10)
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