Creatine, a beneficial peptide
by Ricky Siebeler
Creatine is a peptide composed of several amino acids. Specifically, the compound contains L-arginine, glycine and methionine. Currently it is one of the most used supplements by strength athletes, as it accelerates the recovery of available energy in the cells. Whether you are currently supplementing with creatine or not, your body already uses this compound on a day to day basis. These days there is even some evidence suggesting that creatine has potential benefits for non-athletes. Everything mentioned above explains why it is one of the most studied supplements available. This article will offer some in-depth information about the supplementation of creatine monohydrate, with some additional myth busting.
How does it work?
Without going too in-depth about the body’s energy systems; the body breaks down nutrients such as carbohydrates, fats and ketones to produce ATP (adenosine triphosphate). ATP is used by the cells as a source of energy. By breaking the bond between one of the phosphates, energy is released. This will convert ATP into ADP (adenosine diphosphate) and AMP (adenosine monophosphate). In order to keep a constant supply of energy in the cells, the precursors (ADP & AMP) need to be converted back into ATP.
The body does so by creating a high energy body between the precursors and phosphate groups. Creatine supplementation aids in the acceleration of this process, but before it is able to do so, it is phosphorylated into phosphocreatine by creatine kinase [1-3]. Phosphocreatine aids in this process by increasing the pool of available phosphate groups [4].
Effects of supplementation
As mentioned before, creatine is one of the most studied supplements available. This results in countless studies, aimed towards different effects. This section will only feature studies of importance to strength athletes.
Creatine supplementation has been proven to increase muscle creatine content by a significant amount, proving the effectiveness of supplementation [5-6]. There is also some evidence suggesting that creatine non-responders do exist, who will not benefit from supplementation [7]. There are currently over 60 studies showing a very significant increase in strength levels, after supplementation with creatine. Meta-analyses show effects ranges upwards to about a 7,5% increase in strength [8-9]. As result from creatine supplementation, some water retention may occur, of which the amount differs greatly from person to person. Contradictory to what most people suggest, creatine could be beneficial for more moderate intensity (such as lifting or exercising in the higher rep ranges) athletes as well [10-11]. So far, some of the studies suggest that creatine may also be significantly beneficial when training outside common strength training repetition ranges, these effects seem to get smaller with each additional decrease in intensity. Example: powerlifters get the most benefits, sprinters some benefits, and endurance runners no benefits.
How to supplement with creatine
In order to benefit the most from creatine supplementation, the muscles need to be fully saturated with creatine. In order to achieve/maintain this saturation, creatine is often supplemented each and every day. Creatine can be supplemented through a loading protocol, or without one. The reason for using a loading protocol could be to reach a saturated state early on, and benefit from the supplementation as fast as possible [12]. Some downsides of using a loading protocol would be the possible discomfort in the digestive tract, and the additional costs of using a higher dosage. A typical loading protocol would be to supplement with about 0,3g/per kilogram of bodyweight per day, for about one week [13], followed by a maintenance dose of about 0,03g/per kilogram of bodyweight per day for the remainder of the cycle, or indefinitely [12]. When not using the loading protocol, just start with the maintenance dose which will yield the same effect, after a couple of weeks. Maintenance dose calculations will probably result in a much lower dosage than the generally recommended 5g dose. The 5g dosage is usually taken for one of the following reasons: creatine is very cheap, there is some research suggesting a possible minor benefit to higher dosage supplementation, scoop size, and to make the supplement companies more money.
Additional supplementation tip: Digestive tract discomfort may occur when supplementing without sufficient water intake. Some people may even experience diarrhea or nausea. These effects are more present when using a loading protocol. To counteract some of these effects, drink enough water and perhaps spread out the supplementation over several meals.
Creatine myths
Since creatine is produced by the body, supplementation will suppress the body’s ability to produce its own creatine.
Research does suggest that the production of creatine will be inhibited, if the amount of supplemented creatine is able to cover the vital needs. This inhibition may actually be beneficial to general health, mainly because of the costs (such as essential amino acids) associated with the synthesis of creatine by the body. So far, research suggest that creatine production will go up to baseline levels again when the supplementation is discontinued [14-16].
Creatine may be damaging to the body in the long-term.
There have been several studies testing the safety of long-term supplementation with creatine. Examples of these studies would be the supplementation of 5g on older adults and athletes for about one year. These studies found no negative effects of supplementation [14-16]. This suggests there is no need to cycle creatine out of safety reasons. Some people claim that creatine could be damaging to the liver. This claim is based on the fact that creatine will increase the blood creatinine levels, which are often used as a marker of liver damage. When supplementing with creatine, this marker becomes useless.
There are different forms of creatine available, which lead to better results than creatine monohydrate.
There are countless different forms of creatine on the market today, some of the most well know being: buffered creatine, creatine nitrate, creatine ethyl ester, liquid creatine, and creatine HCl. These are generally being marketed as more potent or better digestible than creatine monohydrate. Some of these forms of creatine have been studied fairly well, and show no significant benefit over creatine monohydrate [6,17-18]. Even though some forms of creatine may be better in theory, so far research suggests otherwise. These forms of creatine are often several times more expensive than creatine monohydrate. Keep in mind that most of the countless studies on the efficacy and safety of creatine were conducted on creatine monohydrate.
My daily meat consumption will provide enough creatine, I don’t need to supplement with creatine for the additional benefits.
According to the previously established maintenance dosage an average 85 kg person would need about 2,5g/per day, while an average person (American) only consumes about 0,85g/per day. Some meats have been shown to contain relatively much creatine: beef 5g/kg, chicken 3,4g/kg. Keep in mind that these numbers are for the uncooked meat, cooking them would denature most of the creatine [19]. Unless you are into consuming a lot of medium rare chicken, supplementation would be needed to attain most of the benefits.
I need to take my creatine after my workout, with carbohydrates.
Timing of creatine has not been proven to be of importance. In theory the body could be more susceptible to the uptake of nutrients after a workout, even though the effects would be minor. Carbohydrates may also slightly improve the uptake of creatine [20]. Both of these effects will not make a difference in the effects of creatine. However, they could aid in decreasing the digestive tract discomfort caused by a creatine loading phase, but during the maintenance phase the factors will not make any difference.
alcohol will diminish the effects of creatine.
Currently there is no research on the specific interaction between alcohol and creatine supplementation. Therefore we are not able to draw any conclusions about this topic, however we are able to hypothesize what kind of interaction we can expect. The uptake and storage of creatine requires water, while alcohol has a diuretic effect. This leads us to believe that alcohol does negatively affect the creatine supplementation. The next question would be to what extent this will affect the benefits of supplementation. Well consider the following: once you consumed the required amount alcohol to dehydrate yourself, you will probably not be able to properly train anyway. When consuming alcohol with moderation (which is not that much), creatine levels should not be affected significantly.
Take home messages:
– To get the most benefits from creatine for the least amount of money, use 3-5g of creatine monohydrate per day, timing does not matter.
– Continued usage for over a whole year have been shown to be safe (at normal dosages).
– Creatine ingested from diet alone is not significant in a normal diet (no medium rare chicken).
References
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