posted February 01, 2000 05:04 PM         

I've seen the info from MMUSA http://www.creatine.com/ and it looks interesting.

Thanks.

[This message has been edited by Jet Driver (edited February 01, 2000).]

posted February 19, 2000 09:48 PM            

Creatine Will Make You Stronger

Creatine does not make you stronger in the short run. It will, however, give you greater endurance if the exercise is dynamic, intermittent, and of high intensity. Many users claim to experience almost immediate increases in peak power, but I really believe this is from a placebo effect. I don't know of a single study that shows creatine having any effect on 1RM bench press or vertical jump. I take that back, one study, paid for by a company that sells a creatine/sugar mixture, did find an increase in bench press 1RM and vertical jump, but I personally believe the results were in error, or at least caused by the aforementioned placebo effect.

Creatine does allow you to do more work. It may also create a cellular environment conducive to further muscle growth. Either of these advantages could lead to greater muscle mass and strength, providing all other conditions are optimal. The trouble is, it's not an overnight cure as many people believe.

The More Creatine You Take, the Better

See if this makes any sense: if I take x grams of supplement z, than taking double-x is better; if taking double x is good, then taking triple x is lots and lots better! Unfortunately, it doesn't quite work that way. If it were, you'd see guys taking inhuman amounts of steroids; amounts that would frighten the rest of this�wait a minute, bad example. They already do. Oh well, either way it's a bad idea, but that's what most athletes are doing with creatine!

For most muttonheads, creatine intake is determined by their economic status. They'll ingest as much creatine as they can afford. The fact is, human muscle appears to have a creatine ceiling of about 5.0 grams per kilogram of muscle. Once that amount is achieved, chances are it can't be exceeded. In fact, most people have about 3.9 grams of creatine per kilogram of muscle tissue, so they can expect to experience a 30 to 40% increase with ingestion.(4)

Therefore, once you've gone through the standard loading phase (20 grams a day, in divided doses, for five or six days), your cells probably contain all the creatine they can handle. Trying to add more is like putting 10 pounds of cement in a 5-pound bag.

Those that think all or most of the creatine they swallow is sucked up, Hoover-like, by muscle cells are mistaken. For instance, in one study, creatine intake in test subjects was very high�up to 70% of a 10 gram dose was retained by the patient. After one week, however, almost all of the administered creatine could be retrieved in the urine. In another study, participants were given 6 five-gram doses per day for three days. On the first day, 40% of the 6 five-gram doses was recovered form the urine. On the second day, 61% of subsequent 5-gram doses was recovered, and on the third day, 68% was recovered.1 It's clear that less and less of the creatine was being absorbed by muscle cells and that a lot of this stuff gets flushed down the vortex of the toilet.

Obviously, there are many factors that affect individual creatine utilization, but generally, after you've reached the saturation point, you probably only need two or three grams a day to keep your cells super-saturated. Of course, if you're a big mutha'�on the order of 200 pounds or above, you might need to up that maintenance dosage to about 5 grams a day, but no more.

Creatine Will Cause Muscle Injuries and Kidney Problems

Trainers around the country have begun to suspect a relationship between creatine and muscle dysfunction. Heavy-duty creatine users seem to be more susceptible to cramps, muscle spasms, and even pulled muscles. Now it's true that creatine seems to act like an osmotic agent, drawing fluid into the cells. This increased water accumulation might result in additional intracellular pressure, thereby contributing to muscle dysfunction. It's possible, but I doubt it.

The truth is, sprinters have been using creatine for some time without even a hint of a problem. Of course, sprinters are notorious for stretching like madmen. If many of these athletes who experience "creatine-related injuries" practiced a little more stretching, their muscle problems might disappear. (Perhaps athletes, like most of us, look for causal relationships between what might be random events and they have to blame injuries on something other than bad luck.) Likewise, although training with weights is practically endemic in most athletic circles nowadays, training smart is as rare as a Hollywood summer movie with a good script. It's more likely that training injuries are caused by muscle imbalances from paying too much attention to certain muscles without equal attention to their antagonistic muscles, e.g., too much quad training without an equal amount of hamstring training.

I will admit, though, that creatine might be causing occasional cramping because of the aforementioned osmotic properties of the substance. If you don't drink enough water, creatine might cause you to cramp. The solution? Try drinking an extra 4 glasses of water a day; more if you're training in hot weather.

As far as any possible kidney damage, excess creatine is removed by the kidneys by filtration�the act does not require any energy.4 Of course, people with already existing kidney problems, or those that are predisposed to kidney ailments, might want to use the stuff cautiously.

Creatine Will Pack On Five to Ten Pounds of Muscle in Two Weeks

Let's get this straight. It's likely that 99% of the initial weight gain experienced by creatine is nothing but water. Creatine will promote amino acid uptake and stimulate myofibrillar protein synthesis, but not in two weeks! Steroids don't even work that well.

If you're lean, taking creatine will engorge your muscles very quickly and you'll look bigger, but the effect is no more magical than filling a balloon up with your garden hose. In fact, some pro and top-level amateur bodybuilders use herbal diuretics while using creatine in an effort to cut down on the "puffy" look experienced by many water-logged users.

Studies on patients who suffer from Type II muscle fiber atrophy have shown that creatine supplementation significantly increases total body weight by 10% and Type II muscle fiber diameter by 34%, but over the course of a year.5 True muscle growth will be enhanced by creatine ingestion, but it's a relatively slow process.

Some Brands of Creatine Work Better Than Others

There's only two things to look for when shopping for creatine: purity and a low price. Creatine is creatine, and despite the bells, buzzers, and whistles added by various ingenious supplement companies, all will have virtually the same effect on your body.

It is true that insulin seems to increase the rate of absorption, but all we're talking about here is speeding up the loading phase. If you take any of the glucose/creatine mixtures available, you'll load the muscles with creatine more quickly than you would otherwise, but that just means you'll reach your muscle cell threshold that much quicker. The same is true of liquid creatine. It's simply absorbed by the body much more efficiently.

If you're concerned about how fast you load, try dissolving your powdered creatine in a warm beverage, like tea. That's how the initial creatine studies were conducted and what they knew then still applies: creatine just doesn't dissolve very well unless you mix it in something warm.

And, if you really want to elicit an insulin response to facilitate muscle cell absorption, you might as well make a creatine sandwich! White bread has a glycemic index of 100, the same as the glucose added to various high-falutin' brands. I'm not actually suggesting that you do that, but the point remains: you can elicit an insulin response (which in turn will help the body absorb more creatine) in many different ways; powdered glucose or sucrose doesn't have to be involved.

Everyone Will Enjoy the Same Benefits from Creatine

According to some estimates, a full 20 to 30% of users don't respond to creatine. No one knows why, but I suspect it might have more to do with using the product incorrectly or sporadically as opposed to some physiological shortcoming. Still, I suspect the number of non-responders is much less than 20 to 30%.

Vegetarians, on the other hand, usually do very well from taking supplemental creatine as they often have very low levels of natural creatine in their muscle cells. Why? They don't eat meat or fish; two foods that contain lots and lots of creatine. Likewise, those that depend heavily on meal replacements (that don't ordinarily contain creatine) might enjoy a greater benefit from supplementation.

Other factors determine creatine effectiveness, too. For instance, Type II muscle fibers have been shown to contain a higher amount of creatine than type I fibers. As proof, creatine levels in the soleus muscle in humans (65% of which is made up of Type I fibers) are significantly lower that that of the vastus lateralis (41% of which is made up of Type I fibers).1

Furthermore, sprinters have higher levels of creatine in their quadriceps muscles as compared to endurance runners. Of course, this might be because sprinters generally have a higher percentage of Type II fibers, so the effect of training can't be discounted.

Exercise also plays a big part in creatine utilization. Studies have found that creatine levels in an exercised leg are higher than that of a non-exercised leg. Therefore, taking creatine without exercising might be largely futile, unless you have some sort of degenerative muscle disease where additional creatine might be useful.

Nutritional factors may play a part in effectiveness, too. A deficiency in Vitamin E might interfere with absorption, as might failing to elicit an insulin response while taking a daily dose of creatine.

Creatine Will Improve Your Athletic Ability

Creatine won't make you jump higher. It won't make you throw harder. And, it won't necessarily allow you to beat that smart-alecky college grad in the bean-bag race at the next company picnic. Creatine helps in those activities that require short, explosive burst of energy, typically lasting less than a minute.

Creatine increases your work capacity. You won't be able to run faster, but it will take you longer to approach exhaustion, which will, in effect, give you a greater overall sprinting speed. Likewise, you won't necessarily be able to lift more weight, but you should be able to lift the same amount of weight a greater number of times.

One study involving sprinters showed that creatine loading (five grams a day for five days) allowed subjects performance capacity to increase by 7% during an initial 15-second sprint and 12% during a subsequent 15 second sprint.2 That means that it took them longer to reach exhaustion.

Fatigue is generally caused by a depletion of phosphocreatine in Type II muscle fibers. So, if you can replenish exhausted phosphocreatine by ingesting more raw creatine, you can probably increase anaerobic ATP production by approximately 5%.3 Researchers used to suspect that creatine supplementation reduced lactate production, but since it causes less dependence on anaerobic glycolysis for resynthesis of ATP, the body produces less lactate.

Again, creatine supplementation might be a good idea for sprinters, but it probably won't help endurance runners.

Hopefully, I haven't caused you to discard your 400-pound, one-month supply of creatine into the local landfill. Creatine is a great supplement; it cosmetically enhances your appearance by making your muscles look more full, and it gives you greater work capacity which, in the long run, will lead to greater legitimate muscle mass and strength.

It is not, however, the end-all and be-all supplement that some manufacturers would have you believe.

posted February 20, 2000 12:20 AM         

And although I agree with the majority of what was written, there is some research that contradicts the renal (kidney) safety of the use of creatine. Research from just a few years ago seems to indicate the safety of creatine use, but the light being shed based on current research is a bit concerning. Here are just 2 of many articles that have me concerned. The sources are cited for reference.

BENZI G Pharmacol Res 2000 Mar;41(3): 255-264
"No research on creatine safety in humans has been set up by specific standard protocol of clinical pharmacology and toxicology, as currently occurs in phase 1 for the products for human use. More or less documented side effects induced by creatine are weight gain; influence on insulin production; feedback inhibition of endogenous creatine synthesis; long-term damages on renal function."

Graham AS, Hatton RC Creatine: a review of efficacy and safety. J Am Pharm Assoc (Wash) 1999 Nov-Dec;39(6):803-10; quiz 875-7 "Consumers should balance the quality of information supporting the use of creatine with the known and theoretical risks of using the product, including possible renal dysfunction."

I hope this is not the case; that creatine is safe for long-term use, but until numerous research projects have demonstrated this then I would proceed with caution.