Spend any amount of time in a weight room, and you'll invariably hear the questions "What's creatine?" and "What does it do and how does it work?"
Despite the prevalence of creatine use as an ergogenic supplement, it is still a largely misunderstood molecule. Let's clear up some of the myths and spell out exactly what creatine supplementation can and cannot do for you and to you.
The Role of Phosphocreatine in Energy Production
Adenosine triphosphate (ATP, 3 phosphates), that energy molecule you probably learned about in high school, is responsible for fueling ALL muscle contractions in the body. Unfortunately, we do not hold enough ATP to power high intensity exercise for more than a few seconds of protracted work. Rather than having a large storage site of this rather heavy molecule, it's much more efficient to simply make new ATP as needed. Your body is doing so as you read this; you may store in the ballpark of 100-200g of ATP at any one time, (depending on body size, muscle fiber distribution, etc.) but can recycle upwards of your entire body weight's worth of ATP in one day.
That's where creatine comes in.
Phosphocreatine (PCr) is part of the phosphogen (ATP-PC) energy system. It's found naturally in red meat and fish, and is also produced normally in the liver and kidneys through a combination of essential and non-essential amino acids. As ATP is depleted, intramuscular phosphocreatine stores act as a phosphate reservoir from which the body pulls the third phosphate needed to synthesize adenosine triphosphate from adenosine diphosphate. Oral supplementation of creatine directly increases the intramuscular availability of phosphocreatine.
Benefits of Creatine Supplementation
So, what can creatine supplementation offer the hard training population?
Consider that ATP stores last no longer than 10 seconds at most during very high intensity exercise. Once that ATP is gone, you're forced to switch into the lactic acid/glycolytic energy system, which necessitates a sizeable decrease in force production. This is easily observable; perform any all-out exercise which requires 90-100% work output, and in less than 10 seconds you will begin to fatigue and power output will diminish.
The more phosphocreatine available, the more ATP can be re-synthesized, the longer you stay within the ATP-PCr energy system, the longer you can sustain a maximal work output. This is particularly valuable for movements such as 1-3RM lifts, 100m sprints, a wrestling scramble, that breakaway sprint from your 10 yard line to the other team's end zone, or any other movement requiring all-out explosiveness or maximal work output.
What's more, having a larger creatine pool speeds re-synthesis time between intense activity, thus improving recovery. Picture a boxer being able to more rapidly recover between all-out 10 punch flurries, a soccer player recovering faster from consecutive sprints, a lifter with less recovery time between sets, or any other sport that involves stop-go bursts of intense activity.
Sounds great, right? Well, let's put it into perspective. Creatine is not going to shave seconds off your 100 yard anymore than it will put 50 lbs onto your squat. It may let you throw one last punch in a combo or get that extra rep you might otherwise miss, but it isn't a miracle supplement. Creatine supplementation offers a reasonable performance increase for anaerobic activity, but it certainly isn't make or break. It also offers no direct benefit on activities utilizing aerobic or lactic acid/glycolytic systems (anything past 10 seconds of max output). Note that this doesn't include short term bursts of maximal work interspersed within less intense activities. For example, a boxer utilizing primarily the lactic acid/glycolytic and aerobic systems would still benefit from creatine when called on to do an all out storm of punches.
Lastly, creatine also readily absorbs water. This may or may not be a benefit, depending on the individual. It has the aesthetic perk of making muscles appear bigger and fuller (they aren't stronger, only filled with a bit more intramuscular water), which would obviously be desirable for a bodybuilder. However, it can also make other tissues appear bloated, depending on how efficiently a person can uptake creatine into muscle cells, which varies. For a weight class restricted athlete, water retention could be problematic. If this is you, I would advise experimenting in the off season with how much benefit creatine supplementation gives performance-wise versus how much weight is gained, or utilizing creatine to train hard, then cycling off a few weeks before your season starts.
Those are the concrete facts.
Creatine also has a litany of "probably does", "could possibly", and "might even" secondary effects.
Studies by Santos et al, 2004, and Cooke and Barnes, 1997, suggest that creatine may improve post exercise recovery and speed recovery time. This is likely from reducing cellular inflammation and damage that comes with the territory of intense activity.
A study by Wyss and Schulze, 2002, have indicated that it may be beneficial in treating certain neurodegenerative brain disorders such as Parkinson's, and may even offer short term memory and problem solving benefits to normal populations.
Studies by Cribb et al, 2007, Burke et al, 1996, and quite a few others have suggested that creatine supplementation improves muscular hypertrophy. Compared to the placebo group, the treatment group showed higher levels of IGF-1 and lean body mass increase. It is unclear whether or not the creatine itself caused these effects, or if creatine's anaerobic performance boost allowed for more intense training, thus leading to increased hypertrophy. Interestingly, these effects were more pronounced amongst vegetarians.
...and so on. There's a lot more unsubstantiated claims on the benefits of creatine supplementation. As in the above cases, there's some compelling science and suggestion being made, but a dearth of a strong body of research still renders these supposed benefits as conjecture.
Contraindications and side effects
Despite conclusive evidence on the safety of creatine, there's still a lingering belief that it will turn your kidneys into jelly or suck the water out of your body faster sprinting in the Sahara.
By and large, creatine supplementation is quite safe. It has practically no known significant, lasting side effects and only minor side effects.
Creatine supplementation doesn't require additional water intake per se; if you aren't adequately hydrated and throw in creatine, then the effects of dehydration will be exacerbated due to the water grabbing nature of the molecule. An athlete who consumes enough water (a topic which will be covered in the future) should experience no symptoms of dehydration.
In the same vein, overdosing creatine can cause a large amount of water to be absorbed in the intestinal tract. This can cause gas, cramping, and discomfort. These side effects are easily prevented or mitigated by avoiding a load-up and following a normal dosing schedule and drinking enough water.
Caffeine and creatine can be taken together, but there is an increased risk of compounding any issues of dehydration due to the diuretic nature of caffeine. If creatine and caffeine are taken together, even more focus must be placed on adequate hydration.
Outside of the realm of predictable effects, there will always be a rare few who have odd reactions. This is true of any supplement or medication, and is unspecific to creatine.
NSAID's may compound any stress excess creatine can place on your kidneys. I wouldn't go chasing 5 Ibuprofen with 20g of creatine, but again this is not likely to be a concern if normal dosage of both the NSAID and creatine are used.
The take home point is that if you do it right, creatine supplementation is safe. If It has no inherent kidney damaging properties. Because creatine is filtered through and puts extra stress on the kidneys, those with nephrological problems should probably consult a doctor before use. Don't be the guy who thinks "one scoop creatine good, 10 scoops better!" and there's a 99% chance you'll have no problems.
For some, a major concern will be the likelihood that creatine supplementation down regulates natural creatine production over a period of months to years. While this has never been conclusively proven, it's probably true. Practically anything produced in the body will be down regulated if it is supplied exogenously. If I started injected myself with insulin, testosterone, antioxidants, or anything else naturally produced in the body, you'd better believe that my own natural production would drop off in response. Your body hates being wasteful and won't expend resources to make something it's getting more than enough of. This is, again, nonspecific to creatine.
The real question is, does supplementation have any lasting effects on natural production? No one really knows. I highly doubt supplementation would or could have any permanent effect on natural creatine production, or any other naturally occurring substance for that matter. You might experience a brief lag time if supplementation stops, following by a quick return to normal synthesis.
Lastly, about ~10% of creatine users will be non-responders, meaning that for whatever reason, they will see no benefit. This is likely due to uptake inefficiency, meaning that not much of the creatine you take actually arrives intramuscularly. If this describes you, fancier forms of creatine with better absorption may be worth a shot.
Types of Creatine
Creatine Monohydrate
This is the basic stuff. Luckily, it's effective, cheap, and generally works just fine. The only real drawback is that it's gritty and not all that soluble, meaning you have to constantly mix or choke down what tastes very much like a big gulp of sand. It can also cause intestinal discomfort, bloating, and so on. Apart from that, There's not a whole lot of reason to stray too far from monohydrate.
Micronized Creatine
Basically the same as monohydrate, just ground to a much finer particle. This increases surface area, supposedly reducing any intestinal side effects. Really, the main reason to buy this over monohydrate is that it mixes easier and tends to be easier to drink. If the taste and texture of monohydrate bothers you, consider spending a little extra on this form.
Creatine Ethyl Esther (CEE)
Touted as being much more bio-available, this form is supposed to elicit far better absorption. It's also supposed to negate any intestinal issues as well as "creatine bloat", which may be helpful for weight class restricted athletes. Lastly, it's claimed to work on monohydrate non-responders. I've never tried it, but it's said to have a truly awful taste in powder form, though capsules are available. CEE is quite a bit more expensive than monohydrate.
Pre Workout Supplement
Usually creatine mixed with caffeine, arginine, beta-alanine, and whatever other proprietary mix used for the intention of causing a whole slew of, if you believe the adds, beneficial effects. Jack3d, NO Xplode, Superpump Max, Nuclear T-Rex Ripped Anabolercised Xtreme Musclez Xploder (just kidding) and other ridiculously name products all fall under this category. Discussion of of these is beyond the scope of this article; just know that most of them contain creatine, sometimes in undisclosed amounts. Extra supplementation may or may not be redundant.
All the Rest
Either prohibitively expensive, unstudied, proven ineffective, or all of the above. Don't waste your time or money.
Creatine type is largely a matter of opinion and taste. If you respond well to monohydrate, I'd stick with that. If you can't stand the texture, turn out to be a non-responder, or get significant bloating/cramping/gas, you might want to give micronized or CEE a shot.
How to Supplement With Creatine
Avoid a loading phase, plain and simple. There's no reason to do it. An excess of ~5g for most people at a time will simply be excreted through the urine, and increases the likelihood of nasty gastrointestinal side effects.
Start with 2-5g of creatine a day. For reference, one teaspoon is about ~5g. You'll probably want to mix it with some kind of juice or sugary drink, probably with your post workout carbs. Studies have suggested that uptake is enhanced with an insulin spike, but more importantly the stuff is usually pretty gritty and I personally can't stomach it with water, milk or shakes. If you can, then there's no problem. Avoid taking it with orange juice or other acidic juices as the acid has been shown to degrade creatine.
Don't pre-mix a creatine solution. It degrades fairly quickly in liquid and should be drank as soon as it's mixed.
Since creatine has to be built up and stored in the system, when you take it isn't very important. Just get in 2-5g a day and within two or three weeks you'll be saturated and enjoying the benefits. To maintain, you really only need to take ~2-3g, but most continue to take 5g because it's easy to just toss a teaspoon in. Either way is fine as a little excess will likely just be excreted.
You can either stay on it indefinitely, or cycle if you have concerns of down regulation of natural production. There's no real evidence that creatine supplementation down regulates natural production, but there's also no evidence that suggests that it doesn't either. This is a personal call. That being said, I would be rather surprised if a normal body wasn't easily capable of resuming normal creatine synthesis once supplementation has ceased, with a lag time of probably no more than a few days in which natural liver and kidney synthesis is depressed.
Lastly, you may not benefit from creatine supplementation if you eat a lot of game animals, red meat, or fish regularly.
References
Santos, R. V. et al. (2004) The effect of creatine supplementation upon inflammatory and muscle soreness markers after a 30km race. Life Sciences, Volume 75(16), pages 1917-1924
Cooke, W., Barnes. W. (1997). The influence of recovery duration on high-intensity exercise performance after oral creatine supplementation. Canadian Journal of Applied Physiology, 22, 454-467.
Wyss M, Schulze A. Health implications of creatine: can oral creatine supplementation protect against neurological and atherosclerotic disease? Neuroscience. 2002;112(2):243-60.
Cribb, P.J., Williams, A.D., Strathis, C.G., Carey, M.F. & Hayes, A. (2007). Effects of wheyisolate, creatine, and resistance training on muscle hypertrophy. Medicine & Science inSports & Exercise,
39 (2), 298-30.
Burke, L.M., Pyne, D.B. and Telford, R.D. (1996) Effect of oral creatine supplementation on single-effort
sprint performance in elite swimmers. International Journal of Sports Nutrition 6, 222-233.
