Section 1. General Information
1.1: What is creatine?
Creatine (also known as alpha-methylguanidinoacetic acid) is perhaps the most popular supplement for improving athletic performance and increasing muscle mass. It also has more scientific support for its use than any other non-hormonal performance enhancing supplement on the market. It is popular among all types of athletes, including amateurs and professionals, teenagers and adults, and men and women.
Creatine, which was first identified in 1832, is an amino acid derivative that occurs naturally in the body. It can be found in the brain, eye, kidney, and testes, but over 95% of the creatine in the body is found in skeletal muscle. It can be obtained through dietary sources and also synthesized within the body from the substrate guanidinoacetate via the enzyme S-adenosyl methionine (SAMe). Guanadinoacetate is derived from the amino acids arginine and glycine. This process primarily occurs in the kidney and liver.
Dietary sources high in creatine include herring, salmon, tuna, beef, and other foods. The combination of dietary creatine and creatine synthesized in the body usually results in the consumption/production of two grams of creatine daily, which is approximately the same rate at which creatine is degraded. Although significant quantities of creatine can be consumed through the diet, the amount is still generally small compared to the intake that can be achieved with supplemental creatine.
Since the early 90's, creatine has been extensively studied for the purpose of improving athletic performance, primarily for high-intensity, short-duration exercise (such as weight lifting and sprinting). There is consistent and overwhelming evidence for a benefit. In addition to research evaluating the effectiveness of creatine in improving athletic performance for a wide variety of types of exercise, research has also begun to evaluate possible benefits in treating muscular, neurological, and cardiovascular diseases.
1.2: How does creatine work?
Research has identified a number of mechanisms involved in creatine's ability to improve athletic performance.
A. The ATP-PCr system
High intensity exercise lasting up to around 2-3 minutes tends to rely on the adenosine triphosphate-phosphocreatine (ATP-PCr) system and anaerobic glycolysis, with the former system being more relied upon during shorter and higher intensity exercises. ATP is the body's primary source of energy, but it is rapidly depleted, forming adenosine diphosphate (ADP).
About 60-70% of the creatine in skeletal muscle is in the form of phosphocreatine (PCr). This is creatine bound to a high energy phosphate, and it is formed by the enzyme creatine kinase. When ATP is utilized for energy and becomes ADP, creatine can donate this phosphate group to the ADP, thus regenerating it back into ATP. By this means, creatine is able to increase the energetic capacity of muscles during high intensity exercise, increasing force output and delaying fatigue.
Although the ATP-PCr system is able to have a significant impact during exercise, PCr quickly becomes depleted. During longer bouts of exercise, energy is primarily derived from glycolysis and fat and carbohydrate oxidation. However, during rest periods, the PCr can be regenerated. Thus, this system is primarily relied upon for very intense bursts of exercise followed by rest periods, such as weight training.
B. Protein synthesis
Creatine may have the ability to increase muscle protein synthesis and/or inhibit protein breakdown, which is supported by the fact that it consistently increases lean body mass in humans. There are multiple mechanisms by which creatine could improve protein balance. The most obvious is that an increase in strength will trigger a greater adaptive response to exercise. A second possible mechanism is that creatine directly serves as a signal for protein synthesis, as it is released following muscle contraction. Also, recent research has indicated the possibility that creatine could increase satellite cell mitotic activity.
It has also been suggested that increasing muscle creatine content leads to an increase in intramuscular water through osmotic action, leading to increased cell hydration, which can stimulate protein synthesis and reduce catabolism. However, whether or not this occurs is still a matter of debate.
arginine and Finally, it has been hypothesized that creatine supplementation can increase protein synthesis by downregulating natural creatine production and thus leading to higher levels of the creatine precursor amino acidsglycine, which can then be used for protein synthesis.
C. Muscle relaxation
Creatine loading has been found to shorten muscle relaxation time by about 20% after maximal contraction in humans. It was theorized that shortening muscle relaxation time could improve recovery time after a contraction, thus allowing for quicker recovery. This is possibly because creatine improves the efficiency of the Ca2+-ATPase pump, which regulates muscle relaxation.
D. Cellular protection
The ability of creatine to facilitate membrane stabilization and act as an antioxidant may help in preventing tissue damage during exercise. Maintenance of ATP levels prevents cell damage through multiple mechanisms, and creatine can also act directly as an antioxidant. It is unknown at this time if this plays a role in the performance enhancing effect of creatine.
Section 2. Effects on Body Composition & Athletic Performance
2.1: What evidence is there that creatine increases muscle mass?
A meta-analysis published in 2003 in the International Journal of Sport Nutrition and Exercise Metabolism extensively reviewed the available research on the effect of creatine on body composition and athletic performance. It pooled the results of 100 randomized, blinded, placebo-controlled trials published in peer reviewed journals. About 80% of these studies measured the effects of short-term supplementation only (a single loading phase), while the others measured the effects of loading followed by a maintenance phase. Much of the data in the following sections is derived from this meta-analysis.
According to the meta-analysis, creatine supplementation was associated with an increase in lean body mass from baseline of 1.6% compared to placebo and an increase in total body weight of 0.9% compared to placebo. In a 180 lb. human, this would be a gain of 2.9 lbs. of muscle and 1.6 lbs. of total weight respectively. Since most of the studies consisted solely of a loading phase, this constitutes a significant increase in lean body mass in a short period of time. Studies of longer duration typically find an increase in lean body mass of 4-5 lbs. relative to placebo.
The effect of creatine on muscle fiber size has also been examined in men undergoing resistance training. In one study, 12 weeks of creatine supplementation increased muscle fiber diameter by 35% (relative to 6-15% for placebo). This effect occured in both Type I and Type II muscle fibers.
2.2: Does creatine also cause fat loss? I've heard it hinders fat loss, is this true?
Most studies do not report statistically significant effects of creatine on fat mass, either positive or negative. The meta-analysis discussed above indicated trends toward a decrease in fat mass and body fat percentage in subjects supplemented with creatine. An increase in lean body mass without an accompanying increase in fat mass will inevitably decrease body fat percentage. Thus, it is likely that creatine doesn't directly cause fat loss, but does improve body composition by increasing the ratio of muscle to fat. However, not enough studies have measured these variables for the extent of this effect to be scientifically established.
Some individuals believe that creatine will interfere with fat loss. This is based on a single study that found significant fat loss in the placebo group, but not the group supplementing with creatine. This study had relatively poor methodology, and is also inconsistent with the results when the research is pooled together. When the available research is examined as a whole, it appears that creatine either does not significantly affect or mildly facilitates fat loss.
2.3: What types of exercise has creatine been found to improve?
Creatine is most effective for exercise periods of high or maximal intensity and lasting for 30 seconds or less. Variables on which creatine has caused improvement for exercise of this intensity and duration include 1 rep maximum, repetitions lifted, work accomplished, time, force production, cycle ergometer revolutions per minute, and power. Creatine can also improve performance on exercises that last 30 seconds to 2-3 minutes, but is less effective. A greater effect has also been found when subjects undergo multiple exercise bouts as opposed to single-bout or first-bout exercise. Finally, creatine appears to be more effective in improving performance on upper body exercises as opposed to lower body exercises, although it causes improvement in both.
Whether or not creatine can improve performance on longer lasting exercises is a subject of debate. While some of the research has found a benefit from creatine supplementation for endurance exercise, most has not. Reviews of the topic do not yet recommend creatine supplementation to improve endurance performance. High intensity exercise bouts followed by periods of rest seem to be necessary for creatine to produce significant results, although future research may provide further clarification.
2.4: What influence does gender, training status, and age have on the effectiveness of creatine supplementation?
Other variables measured in the meta-analysis included the effect of gender and training status. Creatine appears to be equally effective in males and females, and also equally effective in trained and untrained subjects, although individual studies have had varying results.
Some studies have measured the effectiveness of creatine supplementation in older individuals (55 or older) with mixed results. The increase in muscle phosphocreatine after supplementation is not as great in older subjects. While creatine does still improve body composition and exercise performance in this population, the effect is probably smaller.
2.5: What types of athletes can benefit from creatine supplementation?
The effects of creatine in many types of athletes has been researched, sometimes in sport-specific activities. Some of the various populations and exercises that have improved after creatine supplementation are listed here.
Many studies have examined the effects of creatine on resistance training performance, using one rep maximum as the performance measure. A meta-analysis of sixteen placebo-controlled studies on resistance trained males published in 2002 found creatine supplementation to increase one rep maximum for bench press by an average of 15.07 lbs. and one rep maximum for squat by an average of 21.47 lbs. Another review looked at improvements in 1, 3, and 10 rep maximums following creatine supplementation and found an average of an 8% greater increase compared to placebo. The review also found an improvement of weight lifting performance measured by an increase in the number of repititions at a given percentage of maximal strength of 14% relative to placebo.
The effect of creatine (.3 g/kg loading followed by 2.25 g maintenance) or placebo on swimming performance on 50 and 100 y sprints was measured in fifteen Division III swimmers. The subjects given creatine had improved performance compared to pre-supplementation on both events. Another study in junior swimmers found no improvement in single sprints from creatine supplementation, but did find an enhancement of swim bench test performance. Multiple other studies have also found creatine to improve swimming performance.
improved performance on the dribble test, sprint-power test, and vertical jump test. These tasks rely primarily on the ATP-PCr system. failed to improve A recent study examined the effects of three doses of 10 g creatine daily or placebo in twenty male soccer players over the course of seven days. Performance on a number of soccer-related tests was measured. CreatineCreatineendurance performance in these subjects. The authors concluded that creatine improved soccer-specific skills in young soccer players. Four previous studies have also found impoved performance on similar tests from creatine supplementation in highly trained soccer players.
A number of studies have found creatine to improve cycling performance, especially sprint performance followed by short rest periods. Additionally, creatine may even improve endurance cycling performance.
Creatine appears to improve sprint performance, but not to the same degree as most other forms of exercise. While some studies indicate a benefit, others do not. It is possible that the increase in body mass makes a larger difference here.
A study examined the effect of creatine (20 g daily) or placebo for five days on exercise tests in elite rowers. It found that creatine increased the exercise time for anaerobic exercise against a constant load in this study population. However, another study did not find an improvement from creatine supplementation in a high intensity rowing and strength program.
In one study, 20 international level wrestlers were given creatine (four doses of 5 g daily) or placebo and underwent Wingate anaerobic tests. There was significant improvement after supplementation with creatine, but not placebo
Section 3. Safety & Side Effects
3.1: What are the primary side effects associated with creatine?
Creatine is associated with very few side effects and is quite safe. Most reviews on the topic indicate that short-term supplementation has been established to be safe, but there is less data on long term use. The primary side effect is an increase in body weight. People taking creatine have anecdotally reported heat exhaustion, muscle cramping or strains, nausea, vomiting, diarrhea, kidney problems, and stroke. However, the research on creatine, which is quite extensive, has failed to link creatine with any of these problems. These side effects, as well as other reported side effects, will be discussed in further detail in the following sections.
3.2: I just read a news article describing a bodybuilder that got poisoned by creatine and had to have his legs removed and almost died. Is this a likely occurence?
This news article has been posted on many bodybuilding forums, but these side effects are extremely unlikely from creatine alone. As one author (Brudnak M.) notes in Toxicology Letters:
"Negative aspects [of creatine supplementation] have not been so widely reported [in the peer-reviewed literature].... However, negative effects have been reported in magazines and news stories. These often capture large headlines and captivate the audience with their tone. Some of the work has been reported in well-respected journals but it seems the anecdotal reports are the ones that get the most press."
There are a number of problems with this news article. First, it contains a number of factual errors. For example, it states that a month supply of creatine at 5 g daily costs $50.00, when in reality this much creatine can be easily acquired for less than $3.00. The article also describes many questionable medical procedures.
More importantly, nobody has talked to the doctors involved in this case or seen the medical reports. It has also not been reported in the scientific literature. It is all hearsay from a bodybuilder who claims the doctor said his medical problems were because "[his] body wouldn't process it [creatine]." This bodybuilder was also at 2% bodyfat, which is extremely unhealthy. It is likely that his problems were due to use of illegal drugs, his extremely low bodyfat coupled with an intense training regimen, or a combination of those and other factors. This article is no cause for concern, and is a typical example of media sensationalism.
3.3: Many people say that creatine makes you appear bloated by increasing water retention. Is this true?
Whether or not creatine causes water retention is a matter of debate in the scientific literature. Some argue that the rapid increase in body weight is primarily due to increased protein synthesis, while others argue that it is due to increased water weight. The arguments for both sides will be presented here.
synthesis base it on a number of observations. Most importantly, while Those who argue that the increase in body weight is due to proteincreatine leads to measurable increases in total body water (TBW), this is proportional to the increase in body weight. This observation is explained by Kilduff et al. in the International Journal of Sport Nutrition and Exercise Metabolism:
"Supplementation with Cr [creatine] in the present study increased body mass, with the mean increase in the responder group greater than the placebo group after loading and maintenance. This increase in body mass cannot be explained by the increase in TBW, reflecting Cr-stimulated water retention, as there was no significant increase in TBW expressed as percentage of body mass. Despite a significant increase in TBW in absolute terms in the Cr group, if the relative volume of TBW remains constant (as in the present study), the gain in body mass need not be attributed to water retention. Instead, the increase in absolute TBW seen after Cr supplementation may be indicative of intracellular water that normally accompanies dry matter growth. Similar results have previously been found and interpreted in the same manner."
There are other arguments in support of protein synthesis being the primary reason for the increase in body weight as well. Many, but not all, studies support the contention that creatine increases protein synthesis. The rapid strength increases associated with creatine supplementation could not be easily explained by increased water retention. In fact, if the increase in weight was primarily due to water, performance on some activities would likely be hindered, and this is not supported by the research.
On the other hand, there are those who argue that creatine increases TBW relative to body weight. Still, those who argue this call this proposal "speculative" (Powers et al). It is argued that the increase in body weight is too rapid to be explained by protein synthesis. It is also argued that this would explain some of the anecdotal (but as of yet uncomfirmed) side effects, such as cramping, heat exhaustion, and so on, as an increase in intracellular water could decrease extracellular water.
However, the research isn't in agreement over whether the increase in body water from creatine supplementation is primarily intracellular or a more generalized increase in water weight with maintenance of normal fluid distribution. If the latter is the case, as supported by one study, there would not be a mechanistic explanation. Few studies have indicated that creatine increases intracellular water retention in humans, and they have all used bioelectric impedance, which is an unreliable measure.
All in all, while there is some evidence that creatine may cause water retention, the presently available research as a whole suggests that the increased water weight is primarily a consequence of tissue growth. It may also be a combination of the two factors.
3.4: Does creatine cause muscle cramps? Heat exhaustion?
Although some creatine studies find a high incidence of muscle strains and cramps and heat exhaustion, double-blind studies do not report these side effects at a higher incidence than placebo. Many who report these side effects do not experience them again when given creatine a second time. The fact is, these side effects are common among athletes in general, but creatine has not yet been linked with an increased link of any of these occurences.
3.5: Can creatine harm the kidneys?
Going by the presently available evidence, the answer is no. One case report describes a bodybuilder who was taking creatine and had kidney failure, but he was taking 200 g a day along with high doses of anabolic steroids. Every study done in humans on the subject, including controlled studies on athletes who have been taking creatine for up to five years, have found no effect on markers of kidney function at all. It is possible that creatine could pose a problem in individuals that already have impaired kidney function.
3.6: Is creatinine toxic to the kidneys?
Creatinine is the primary breakdown product of creatine. It is not toxic to the kidneys at all. Creatinine levels are commonly used as a tool to determine kidney function, as high creatinine levels are commonly a symptom (not a cause) of impaired kidney function.
3.7: Can creatine harm the liver?
In one animal model, high doses of creatine can lead to inflammation of the liver. It is important to note that rodent models are particularly misleading with creatine, since their physiology differs from humans so much in this respect. A retrospective study found no difference in liver enzyme levels in athletes who took creatine for as long as four years relative to controls. Another study measured the effects of creatine loading on liver enzyme levels in nationally competitive athletes and found no significant change. Thus, there is no evidence that creatine is harmful to the human liver.
3.8: Can creatine cause cancer?
It is theoretically possible that creatine could increase the risk of cancer, but very unlikely. Creatine and creatinine are precursors to some known mutagens, especially in the presence of certain pathogenic bacteria (such as E. coli). In healthy individuals, the bacteria capable of doing this are present only in very low numbers. They may also possibly be kept in check with probiotic supplementation. Also, many antioxidants have been found to reduce the carcinogenic effect of the compounds that may be produced.
Although a theoretical mechanism exists, creatine has not been linked with increased cancer risk. In fact, in some animal studies, it inhibited tumor growth. Coupled with the other health benefits of creatine, it is unlikely that this constitutes a significant concern, although it may with lifelong supplementation. Nevertheless, for those who are worried about this, it would be prudent to supplement with probiotics and some basic antioxidants (vitamins C & E, phytonutrients, etc).
3.9: Is there a danger from impurities in creatine products?
A few years ago there was a media scare related to the possible presence of dihydrotriazine in creatine products. It has been pointed out that this information came from a source with bad methodology, and that test results can be easily misrepresented to show the presence of this compound. The majority of creatine comes from a single company, and their creatine has been tested many times and dihydrotriazine has never been found. It is best to get a brand of creatine that carries the Creapure label.
3.10: Can teenagers take creatine?
through their diet. Therefore, while Most sources do not recommend that teenagers use creatine. However, many studies have examined the effect of creatine on teenagers and failed to find any adverse effects, nor has a mechanism been proposed by which creatine could pose a danger to teenagers. A large percentage of high school athletes use creatine without reports of serious side effects. Even teenagers who do not take creatine supplements get some creatinecreatine should be safe in teenagers, this question has not yet been subjected to rigorous scientific study.
3.11: Can pregnant or nursing mothers take creatine?
Pregnant or nursing mothers should not take creatine, as the safety is not established in this population.
Section 4. Dosage & Optimal Use
4.1: What dosage should be used? Is a loading phase necessary?
"Loading" refers to the practice of taking larger than normal doses for the first few days of supplementation to maximize muscle creatine stores as quickly as possible. This is followed by a maintenance phase, during which a smaller dose is taken daily to maintain the high levels of creatine.
Loading is not necessary, but it is beneficial. In one study, a maintenance dose (3 g/day) took thirty days to maximize creatine stores. On the other hand, a loading dose (20 g/day) maximized muscle creatine levels in only two days. Normal maintenance doses fall in the 3-5 g range (2 g has been found to be insufficient), although some take as much as 10 g, while 20-30 g (usually 20 g) is used for loading. Some sources recommend a loading phase of 6-7 days, but this appears to be unnecessary. Given that stores are maximized after two days of loading, 2-3 days should be sufficient. One study indicated that resistance training athletes can utilize around 50 mg/kg daily of creatine. A maintenance dose of 5-10 g daily is recommended to ensure that enough is being taken. Taking more than this for maintenance is generally a waste of creatine.
4.2: How and when should creatine be taken?
Creatine usually comes in powder form. Although capsules are available, they are significantly more expensive and most prefer powder. Creatine can be mixed in most drinks. During loading, it is customary to divide the creatine into 3-4 doses spread throughout the day (3 doses of 10 g or 4 doses of 5 g). During maintenance, 1-2 doses daily (usually of 5 g each) are used. Taking one of the doses pre-exercise on exercise days is recommended. Also, if some meals contain more carbohydrates than others, creatine should be taken with the high carbohydrate meals.
Some believe it is best to take creatine throughout the day to maintain elevated blood levels. However, once muscles are saturated with creatine, it takes a long time for muscle creatine levels to return to baseline (30 days). In the big picture, maintaining elevated blood levels around the clock is relatively inconsequential, as muscle creatine levels will be maintained at near-maximum with once daily dosing.
4.3: Is it necessary to cycle creatine?
stores are maximized. For this reason, some recommend cyclic use of production, but studies have found that natural production is restored very quickly after supplementation discontinues. Therefore, it should be most effective to use When exogenous creatine is administered, natural production of creatine is drastically reduced. Creatine transporters also downregulate as creatinecreatine to allow natural production to return to normal. However, there is no evidence that this is necessary. Because supplemental creatine leads to creatine levels much higher than would be produced naturally, there is no reason to try to maintain natural creatine production while trying to take creatine – it will not alter the effectiveness of the creatine. If creatine is taken consistently, muscle creatine levels are maintained at their maximal level, and do not decrease. Some believe that if creatine is taken for too long it could lead to permanent shutdown or a decrease of natural creatinecreatine on a constant basis.
4.4: How bioavailable is creatine?
The total bioavailability of creatine is unknown. Some creatine is degraded to creatinine in the GI tract, but the amount is probably low (one study estimated about 2%). It is believed that it is actively transported in the intestine by a saturable transporter. As the dosage of creatine increases, the time to maximal concentration and half-life increase. High doses, such as 20 g, cause an increase followed by a plateau in blood creatine levels lasting about six hours before dropping.
transporter. This transporter is highly selective for The main limiting factor for muscle creatine uptake is the creatinecreatine. Another naturally occuring compound, beta-guanidinopropionic acid, also competes for the creatine transporter. As levels of creatine in muscle tissue increase, the creatine transporter downregulates. This makes it so muscle tissue can only store a certain limited amount of creatine. Although this amount is not maximized in most individuals not supplementing with creatine, the limiting role of the creatine transporter makes it so creatine supplementation beyond a certain dosage does not yield any additional benefit.
Other than muscle creatine content, there are some other factors that may influence the creatine transporter. These include exercise and the levels of some hormones, such as catecholamines, thyroid hormone, insulin, and insulin-like growth factor 1 (IGF-1).
4.5: I've heard that you should not mix creatine in acidic beverages, because it will destroy the creatine. Is this true?
The short answer is, no. You do not want to mix creatine in an acidic beverage such as orange juice, or any other liquid for that matter, and then store it for a long time before taking it. However, mixing it with any beverage and drinking it soon thereafter is fine.
Those who point out that creatine is unstable in acids fail to point out exactly how unstable it is, as this is a relative measure. The degradation half-life of creatine follows an inverted U along the pH scale, with the bottom estimated to be somewhere around a pH of 4. In acids about the strength of orange juice (pH of 3), creatine still has a degradation half-life of over seven days. In substances that are even more acidic (such as stomach acid), the degradation half-life is actually much longer – for example, it is 55 days at a pH of 1.4. This means that creatine can easily make it through the digestive tract with very little degradation.
4.6: What methods can be used to increase creatine uptake?
Exercise is one of the best ways to increase muscle creatine uptake. It has been demonstrated that when one leg is exercised, but not the other, the exercised leg has a much higher rate of creatine uptake. An increase in blood flow and changes in creatine transporter activity may both contribute to this effect. After the loading phase, it is recommended that maintenance doses be taken 30-90 minutes prior to exercise.
uptake is consumption of high glycemic After exercise, the second most reliable way to increase muscle creatinecarbohydrates. One study found that when creatine was ingested with carbohydrates, there was a 60% greater increase in muscle creatine levels than with creatine alone. The primary mechanism for this effect has been suggested to be insulin, which may stimulate the creatine transporter.
uptake, with a recommended amount of 100 g of According to the presently available research, a large amount of carbohydrates is necessary to significantly increase muscle creatinecarbohydrates per 5 grams of creatine. Another study suggests that the same effect may be achievable by about 50 g each of protein and carbohydrates. Given the benefits of both of these macronutrients during exercise, this regimen may be optimal.
Ideally, both the protein and carbohydrates taken with creatine should be high glycemic. The protein source should be a type of whey protein, and dextrose or another simple sugar should be used for carbohydrates. Fructose should not be used, as it does not produce a significant insulin response.
4.7: What supplements can be taken to maximize the effects of creatine?
Alpha lipoic acid
Alpha lipoic acid (ALA) is a potent antioxidant compound that causes significant improvement in patients with type II diabetes by increasing insulin sensitivity. It has been theorized that ALA could increase muscle creatine uptake in healthy humans by increasing muscle insulin sensitivity and thus enhancing creatine uptake. Although the effects of ALA on insulin sensitivity in healthy humans is not established, one study compared the effects of 20 g creatine (CR), 20 g creatine and 100 g sucrose (CRS), and 20 g creatine, 100 g sucrose, and 1000 mg ALA (CRSLA) daily on healthy, recreational weight liftters (who did not exercise during the study) without impaired glucose metabolism. They found an equivalent increase in body weight in all groups over the duration of the study, while the CRSLA group had greater increases in both phosphocreatine and total muscle creatine, suggesting that ALA did indeed have an effect.
There were a number of problems with this study, so the results should not yet be taken for granted. First, the subjects were not exercising, which does not reflect real world conditions. Second, the increases in muscle creatine content in the groups not given ALA were lesser than they normally are in exercised subjects supplemented with creatine. Therefore, it is unknown if the effects of ALA and exercise can be additive. In any case, taking ALA with creatine may afford a benefit, although 1000 mg is a rather high dose, so 600 mg daily is recommended. This amount of ALA should not be taken without carbohydrates.
HMB is a metabolite of the amino acid leucine. In the scientific literature, there is a general consensus that after creatine, it has more scientific evidence for its effectiveness than other performance-enhancing supplements. It has also been found that creatine and HMB may additively increase lean body mass and strength. The mechanism of action of HMB is not well known. It is significantly more expensive than creatine, and most products that combine the two inflate the price even further. For those who choose to supplement with HMB, I recommend saving money by buying a pure HMB product and taking it along with creatine rather than buying a product with both ingredients. It is also easier to manipulate dosages this way.
4.8: What other ingredients are commonly found in commercial creatine products?
There are many "creatine replacement" products available today. They are primarily marketed as "improved creatine." The different forms of creatine and the validity of the rationale behind these products will be discussed later on. Following is an examination of some of the ingredients found in these products.
Arginine is an amino acid that has become popular as of late due to its ability to increase nitric oxide (NO) levels. There are also many derivatives that are advertised as being more effective. While the utility and safety of arginine is a subject of much debate, the general consensus is that it has limited ability to improve performance or alter body composition but offers a cosmetic benefit by increasing vascularity. In any case, L-citrulline or citrulline malate is suggested as an alternative (see below).
Citrulline and citrulline malate are preferable to arginine, as citrulline has a greater ability to increase NO levels, and there is also more evidence that it improves athletic performance in humans. It should also complement creatine well.
Taurine is an amino acid that is abundant in the human body. It has a number of positive effects on health. However, the evidence that it improves athletic performance or body composition is presently limited. While it improves exercise endurance in rodents, research in humans is limited. Nevertheless, it is a worthwhile ingredient to take, given the low price.
Glutamine is another abundant amino acid in the human body that has become popular among bodybuilders. Multiple studies have measured the effects of glutamine in athletes and failed to find a positive effect, although one analysis indicated that it may lower the risk of infection in long-distance endurance athletes. There are also some downsides to glutamine supplementation. For example, it has been found to decrease glutathione levels in healthy people (while it has the opposite effect in those with critical illness). Glutathione is a very important in the body's defense against oxidative stress. Glutamine also may decrease NO levels.
transporter, and unlike Glycocyamine is the precursor to creatine in the body. Although this sounds like a good thing, glycocyamine competes with creatine for the creatinecreatine it cannot act as a phosphate donor. Therefore, glycocyamine can be expected to reduce the effectiveness of creatine.
Guanadinopropionic acid (GPA) acts similarly to glycocyamine in the body – it competitively inhibits the creatine transporter, depleting creatine levels. GPA is also more potent than glycocyamine.
improves the effects of One study conducted at Western Washington University compared the effects of placebo and creatine plus magnesium (800 mg), with the magnesium either in the form of magnesium oxide or magnesium-creatine chelate. The magnesium-creatine chelate increased body weight, knee extension peak torque, and power, while the creatine and magnesium oxide group had increased body weight and power only. Because there was no creatine only group, this cannot be taken as solid evidence that magnesiumcreatine supplementation (as some companies claim). However, since magnesium is inexpensive and can have multiple benefits for the athlete, it does not hurt to take some magnesium when supplementing with creatine.
4.9: Does caffeine negate the effects of creatine?
Many believe that caffeine will interfere with the effectiveness of creatine. There are a few reasons for this belief. The primary reason is that one study published in 1996 found that while muscle phosphocreatine concentrations were increased by both supplementation with creatine and supplementation with creatine and caffeine for six days, there was a significant improvement in dynamic torque production only in the group that consumed creatine but not caffeine. A second study found that caffeine, which increases muscle relaxation time, kept creatine from decreasing muscle relaxation time.
and and The results of these studies should be treated with caution. In the study that indicated that caffeine may block the effects of creatine, there were only nine subjects, divided into three groups (placebo, creatine, creatinecaffeine). Another double-blind study (Gill et al.), although not appearing in the peer reviewed literature, compared the effect of creatinecreatine plus caffeine on maximal cycle sprints in fourteen subjects and found no significant differences between the groups, indicating that caffeine may not interfere with the effects of creatine. Another consideration is that in many of the studies showing creatine to improve athletic performance, coffee was the delivery vehicle. Also, the relevance of creatine's effect on muscle relaxation time to its performance enhancing effect has not been established. Finally, caffeine can improve athletic performance through multiple mechanisms, which may help to counteract any negative effects it has. So, while it is possible that caffeine interferes with the effect of creatine, more research is needed before this can be taken as a given.
intake has only minimal effects at most on hydration status. Although insulin resistance may be a concern, it is commonly overstated, especially where Outside of the scientific literature some have argued that caffeine would interfere with the effects of creatine by blocking cellular hydration or causing insulin resistance. However, studies have found that caffeinecreatine is concerned. Tolerance quickly develops to the effect, and caffeine does not interfere with exercise-mediated increases in insulin sensitivity. More importantly, two studies (the one mentioned above and a pharmacokinetic study) indicate that caffeine does not blunt the increase in intramuscular creatine from creatine loading.
4.10: What is a creatine non-responder?
Studies have found that about 20% of the population does not respond well to supplementation with creatine. Whether or not someone is classified as a responder to creatine is determined by their muscle creatine uptake after supplementation. If the increase in muscle creatine levels from creatine supplementation is less than 20%, a person is labelled a non-responder.
in muscle tissue. Since muscle tissue can only store a certain amount of The reason non-responders exist is not entirely clear. Some, but not all studies have correlated lack of response with high initial levels of creatinecreatine, those with initially high levels will only have a minimal increase from supplementation. People with very low creatine diets, such as vegetarians, have lower levels of creatine and a greater response to creatine supplementation than the rest of the population. However, in the general population as a whole, protein intake has not been correlated with creatine response rate.
One study found that subjects had higher levels of muscle creatine after five months of resistance training, indicating that adaptations due to training could possibly lower the creatine response rate. On the other hand, another study indicated that trained and untrained subjects exhibit the same response from creatine, and creatine also appears to be equally effective in both groups at improving exercise performance.
supplementation will likely increase muscle All in all, the research on who responds to creatine and why is inconsistent and muddled. It can also be said that there is no such thing as a "non-responder," but rather varying degrees of response, since creatinecreatine levels by at least a small amount in every individual. While this will not be enough to see a noticeable difference, it will still help. In any case, it would be difficult to determine if one is a non-responder (or low responder) without a muscle biopsy, although whether or not a rapid change in body weight occurs may be an indicator.
4.11: Is there any way for creatine to work in a non-responder?
The only factor that could make a difference that has been identified in the research is carbohydrate intake. When creatine is taken along with high amounts of carbohydrates, there is less variation in response. Many believe that there are certain products that will make non-responders into responders. This is very unlikely – it is much more likely that these products just produce results related to the other ingredients. As noted above, the amount of creatine in muscle tissue simply cannot exceed a certain amount. Therefore, if one has initially high levels of creatine, they will not get a strong response from creatine supplementation no matter what. It is impossible to "supersaturate" muscle tissue with creatine. If one believes they are a non-responder and have tried taking creatine while carbohydrate loading, the best solution is to stop worrying about creatine and try other supplements.
4.12: What are the different forms of creatine available? Are they better than creatine monohydrate?
Many "new and improved" creatine products have appeared over the years. This section will discuss some of the various types of creatine that have appeared over the years.
This is creatine that has been micronized into smaller particles. Most creatine products now available are micronized. Some believe that this process increases effectiveness, and others believe that it may reduce gastrointestinal discomfort (although creatine has not been found to cause this in placebo controlled research). In any case, there is little difference between this and creatine monohydrate, and they are generally priced the same, so either will do.
Creatine supplements are normally attached to an H2O molecule (creatine monohydrate). Anhydrous creatine, in the presence of water, quickly becomes creatine monohydrate. Therefore this supplement produces identical effects to creatine monohydrate.
Effervescent creatine (dicreatine citrate)
Effervescent creatine fizzes when you mix it. That is the only real difference. When mixed, it is quickly converted into creatine and citric acid (Ganguly et al).
Of all the forms of creatine available, creatine serum is the least desirable. Creatine serum is advertised as having various advantages while still being stable. However, creatine is simply not stable enough in liquid to have an acceptable shelf life. One study found that liquid creatine products contained less than 2% of the creatine that the label claimed. Another study found that creatine improved sprint cycling performance, while creatine serum did not.
Buffered creatine (Kre-Alkalyn)
Buffered creatine is usually advertised as being more stable. As discussed above, the stability issue with creatine is overstated, and oral bioavailability is not a limiting factor. Creatine monohydrate is also stable enough that elevated levels are detectable in muscle tissue 30 days after supplementation.
Ironically, buffered creatine may actually be slightly less bioavailable. Since the stability of creatine is higher in strong acids than weak acids, buffering may actually only serve to increase the rate of degradation in the stomach.
Tricreatine malate is creatine attached to malic acid. No studies have been conducted on tricreatine malate. In all likelihood, it becomes creatine and malic acid in solution. Malic acid may have some benefits in its own right, but it is doubtful that tricreatine malate will increase muscle creatine levels any further than creatine monohydrate is capable of.
Creatine ethyl ester
This is the newest development in creatine products. The story is generally the same as with the previous forms of creatine: bioavailability is supposed to be improved, it is supposed to be more effective, and so on. Again, even if this is the case on a per gram basis, there is no evidence that there is a benefit over creatine at full dosage. While it is possible that this form has advantages, this contention is not yet scientifically supported.
4.13: What brands of creatine are recommended?
There are many quality creatine products available. Some of my recommendations for low price, high quality products are:
Now Creatine Powder
Optimum Creatine Powder
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Darkhorse on 11-03-2005, 12:47 PM
Types of Creatine:
One of the original forms of creatine introduced in supplement form, monohydrate has been the type most widely researched and promoted.
· one of the lowest priced forms of creatine
· available in a wide variety of supplements
· unless it has been micronised, the chances of gastrointestinal problems will be higher due to the larger particles
This is one creatine molecule with the addition of one molecule of citric acid. The addition of citric acid is believed to help in energy metabolism.
· dissolves easily due to its solubility
· only contains 2 grams of actual creatine per 5 gram serving
· sour taste
This became very popular due to the addition of the phosphate molecule. Before creatine can be utilised by the body it must first bond with a phosphate molecule. The belief was that by adding the phosphate molecule externally that the creatine phosphate would, when consumed, be utilised more quickly. However, this theory has never been proven.
· more expensive than monohydrate
· very few products are currently available
This is one molecule of creatine bound with one molecule of malic acid. Malic acid is commonly found in fruits and vegetables but it is also produced internally by the human body. It plays a part in deriving adenosine triphosphate (ATP - refer back up to 'what creatine does') from food.
· dissolves easily
· less chance of gastrointestinal problems
· supporting research is hard to find
Pyruvate is a by-product produced in the body during the normal metabolism of carbohydrates and proteins. It is also present in foods such as red apples, cheese, and wine. When glucose breaks down, it produces two molecules of pyruvate. If oxygen levels in the body are high, the pyruvate breaks down into carbon dioxide through a series of reactions as part of the Krebs Cycle (a series of chemical reactions within all living cells that utilise oxygen as part of cellular respiration). If oxygen levels in the body are not sufficient, then the pyruvate is broken down, anerobically, to form lactic acid. As lactic acid levels in the body increase, performance levels decrease. As mentioned earlier, creatine has lactic acid buffering properties and so is believed to extend this process and the user's ability to workout longer. Pyruvate also stimulates glucose extraction from the bloodstream and into muscle tissues.
· increased endurance
· high intakes of pyruvate can trigger gastrointestinal problems such as gas, bloating, and diarrhoea
This is one molecule of creatine bound to one molecule of tartaric acid. Tartaric Acid is found in wines and is used in foods to produce a sour taste or as an antioxidant. This is one of the newer forms of creatine currently available but very little is known about its future. Refer to the last point under 'Con:'.
· high stability rate
· very few products are currently available
· tartaric acid inhibits the production of malic acid and is a muscle toxin which can cause paralysis or death at a dosage above 12 grams
The presence of the magnesium is thought to protect the creatine from the acidic conditions of the stomach and thus enable more of the creatine to be absorbed and utilised. Magnesium is also utilised in the conversion of creatine phosphate into ATP. This bonded form of creatine has also been found to increase fluid uptake by muscle cells.
· preliminary research has supported all of the above claims
· very expensive
This is creatine monohydrate with the water molecule removed.
· provides 4.70 grams of actual creatine per 5 gram serving
· similar side effects as monohydrate
The bonding between the creatine and HMB (betahydroxy-beta-methylbutyrate) works in a similar manner as with magnesium in that it enables more of the creatine to survive the acidic conditions of the stomach and subsequently be absorbed and utilised. HMB on its own is associated with aiding muscle growth and recovery.
· enhanced absorption of available creatine
· a more expensive form of creatine
Creatine Ethyl Ester HCL (hydrochloride):
In this case, creatine is bonded with an ester (ethyl alcohol). An ester is a compound formed from the reaction between an acid and an alcohol. Since creatine monohydrate is not very soluble in water, it has difficulty penetrating muscle cell membranes which are made up of lipids (fats). Also, once it comes in contact with any liquid, it gives up its' hydrogen atom which results in it being positively charged at one end and negatively charged at the other. As a result, creatine must rely on transporters to help it bridge this membrane. As it sits outside the cell membrane, it draws in more water (outside the cell), producing the bloating people associate with taking creatine monohydrate. It also begins to degrade and form creatinine. The addition of an ester means that the creatine does not have to rely on transporters to obtain access to muscle cells. Once inside the muscle cell, the ester is removed and the creatine begins to draw water into the cell.
· enhanced absorption rate
· lower dosage rate
· side effects associated with monohydrate are reduced
· more expensive form of creatine
Creatine Alpha-Ketoglutarate (AKG):
As mentioned above for creatine ethyl ester, creatine relies on transporters to help it bridge the cell membranes of muscle tissues. When an insufficient number of transporters are available, the creatine will sit outside the muscle where it will not be utilised. AKG acts as a transport molecule and thus enables more creatine to enter muscle cells and be utilised at a quicker rate. You will also see AKG used with other supplements to act in a similar manner.
· enhanced absorption rate
· more expensive form of creatine
This is a finer powdered version of creatine monohydrate.
· less chances of gastrointestinal problems
· is available in more and more products
· more expensive than monohydrate
This will either be a creatine monohydrate or creatine citrate with the addition of bicarbonate (sodium or potassium) and citric acid. It is the bicarbonate and citric acid which produces the reaction when water is added. The creatine is dissolved and suspended as a result of the reaction. Creatine citrate is more soluble in water than monohydrate and therefore would be the better choice of the two if using this type of a delivery system. However, the actual creatine content of citrate based creatines is low (2.0 grams per 5.0 gram serving).
· dissolves more readily
· sugar content in some products can be high
· actual creatine content may be low
· manufacturing process and packaging of the finished product must adhere to strict guidelines
· few products are currently available
This is very similar to effervescent creatine but without the fizzy effect.
· greater solubility by changing the pH value when added to water
· few products are currently available
· despite advances made in trying to suspend creatine in a liquid, it is still considered an unstable form
Creatine in a formed product source:
Creatine, of various types, is used to make a variety of convenient products ranging from nutritional bars, tablets and capsules, to chewable gums.
· very convenient form
· actual creatine content may be low
· actual creatine which is absorbed may be low
· there is the possibility of not maintaining proper hydration when using creatine in this form
Last edited by Sleazy; 04-25-2006 at 07:50 PM..
Darkhorse on 11-18-2005, 11:53 PM
In the future it'll be better for you to put your questions in the supplement section. You'll get plenty of feedback there. ;)
EricT on 04-05-2006, 04:48 PM
Q: Is there any benefit to cycling creatine? Does my body become accustomed to the creatine and become less efficient at using it?
A: Lyle Mcdonald:
I don't think so. The usual arguments (and there is research behind the concepts but not, in my opinion, the interpretations) regarding creatine cycling are that chronic use causes down-regulation of the transporter and down-regulation of the body's natural synthesis of creatine. Both are logical effects of keeping the body saturated with an outside source. But so what? As long as your muscles stay supersaturated, you should get whatever effects are going to occur (in terms of energy production, increased leverage from water storage, and the rest).
This is a good question and one that, unfortunately, does not have a clear-cut answer. A few years back researchers decided to take a look at what happens during long-term creatine supplementation. (1) The study found that chronic administration of creatine does, indeed, lead to a down-regulation of the creatine transport protein, which is responsible for the uptake of creatine into cells (It should also be remembered that creatine supplementation leads to the down-regulation of endogenous creatine production. (2)) The authors hypothesize that since human muscle has an upper limit for creatine content, the down-regulation occurs to prevent the accumulation of excessive intramuscular creatine. They conclude that to prevent this down-regulation, athletes should use creatine for no more than 3 months straight before taking at least a month off. The problem is, as the authors themselves point out, that the down-regulation of the creatine transporter occurs to prevent the accumulation of excessive intramuscular creatine. So, while the endogenous production and uptake of creatine will indeed be down-regulated, this should only result, not in a (substantial) decrease of intramuscular creatine, but in an end to further increases in intramuscular stores. If, however, you remain unconvinced, I suggest trying both protocols to test for yourself whether cycling has merit. In my experience, it does not.
1. Guerrero-Ontiveros ML. Wallimann T. Creatine supplementation in health and disease. Effects of chronic creatine ingestion in vivo: down-regulation of the expression of creatine transporter isoforms in skeletal muscle. Molecular & Cellular Biochemistry. 184(1-2):427-37, 1998 Jul.
2. Wyss M. Kaddurah-Daouk R. Creatine and creatinine metabolism. Physiological Reviews. 80(3):1107-213, 2000 Jul.
A: Robert Thoburn:
Before I start, I’m going to assume that not everyone who reads this article is familiar with the use of creatine supplements.
Your body produces creatine. As we’ll see, the vast majority of it ends up inside your muscles, just as it does in animals. Thus, creatine can also be obtained from the diet, as by eating animal muscles--beef, for instance.
In a nutshell, creatine is typically used by bodybuilders and like-minded fitness enthusiasts to: (1) increase lean body mass (a 2-4 pound gain is not unheard of); and (2) increase the capacity of their muscles to perform intense work, like firing out a heavy set of squats or bench presses at the gym. The latter may be due to the enhancement by creatine supplementation of muscle fiber relaxation (i.e., your muscle fibers can relax more quickly during contraction, thereby increasing their power output) and resistance to fatigue (i.e., your muscle fibers can generate a given amount of force for longer).
Getting ‘accustomed’ to creatine
Now back to your questions. Simply put, the answer is that yes, your body does become ‘accustomed’ to creatine and begin to use it less efficiently with prolonged supplementation.
To understand how this may occur, let’s start at the biological target of your creatine supplements, your muscle fibers.
The bulk of your muscle is made up of muscle fibers. Making these muscle fibers bigger is the ‘Holy Grail’ of cosmetically-oriented bodybuilders like you and I. These fibers are also the site of ~95% of your creatine stores.
Once your muscles are saturated with creatine, you’ll start peeing more of it out.
Unfortunately (depending on your perspective), your muscle fibers can only hold so much creatine. Once they’re full (such as after ‘loading’ with creatine), adding more creatine to your diet than is required to maintain this level is a waste: You’ll just end up peeing more of it out (see Snow and Murphy, 2001 and references therein).
‘Cycling’ creatine: Is there a basis for it?
Unlike some bosses, your muscle fibers don’t have an ‘open door’ policy. Not when it comes to nutrients, anyway. That is, creatine can’t just come and go as it pleases.
There’s a lot more creatine inside your muscle fibers (i.e., intracellularly) than outside (i.e., extracellularly). Thus, if anything, the tendency is for creatine to exit the muscle fiber rather than enter it. Transporting creatine inside therefore requires work.
The work of transporting creatine into your muscle fibers is performed by at least one type of transporter, which is actually a protein. For our purposes, you can think of this protein transporter as a ‘gateway’ that spans the membrane that encloses the muscle fiber. Many such gateways are distributed throughout the muscle fiber membrane, providing numerous possible sites for creatine uptake.
Work requires energy. The energy used in transporting creatine inside your muscle fibers ultimately comes from adenosine triphosphate (ATP). ATP can be broken down to release energy. Some of this escapes as heat, and some is free to be used to perform work, such as creatine transport. The creatine transporter also seems to be dependent on the presence of certain minerals (e.g., sodium, chloride; possibly magnesium, calcium).
As your muscle fibers fill up with creatine, the activity of the creatine transporter seems to rise briefly, and then fall. This so-called ‘down-regulation’ may be most pronounced in your fast-twitch (a.k.a. type II, or ‘white’) muscle fibers -the fibers, incidentally, that tend to be the most responsible to your muscle-building efforts.
Is there any use in ‘cycling’ creatine?
The fact of the matter is that the proposed benefits of creatine ‘cycling’ have not been proven.
As many of you already know, when creatine is transported into your muscle cells, it is attached to a phosphate group to become phosphocreatine (PC). When PC is broken down, it releases energy that can be used to very quickly re-synthesize ATP, without the need for oxygen. Thus, PC allows your muscle cells to produce lots of force in short ‘bursts’, such as is requiring during an intense iron-pumping workout.
PC levels may fall with long-term creatine use (van Loon et al., 2003) and this may be due to transporter down-regulation (van Loon et al., 2003). Dr. Theo Wallimann (Lourdes et al., 1998) therefore suggests consuming creatine for no longer than 3 months at a time, followed by a 1-month ‘creatine-free’ period to avoid complications of creatine transporter down-regulation.
Note, however, that no studies have been performed to demonstrate the superiority of one method of creatine ‘cycling’ versus another (or vs. not cycling at all). Wallimann seems to base his advice on rodent studies, cell studies, and reports of neuromuscular disease linked to defects in creatine transport.
An alternative to cycling might be to simply consume smaller amounts of creatine each day so as to gradually build your muscle creatine levels up to the point of saturation. Thereafter, consume as little creatine as you need to maintain your gains.
How much is that? About 2 g creatine per day. Interestingly, though one study found 2 g to be inadequate to prevent PC levels from falling to pre-supplementation values following the loading phase, the gains in lean body mass and exercise performance realized by the subjects were maintained (van Loon et al., 2003)!
Think about it this way: Consuming, say, 20 or more grams of creatine day is going to expose your body to more of this substance than the human species ever encountered during virtually its entire evolutionary history. Does it not seem reasonable to suggest that a more moderate intake of creatine might be more efficient, if not safer, in the long-term?
Oh, and remember that at least in the first 24 hours of supplementation, creatine transport into muscle will be accelerated by consuming creatine with carbohydrate (e.g., dextrose) (see discussion in Snow and Murphy, 2001).
Creatine isn’t just for Bodybuilders
Finally, it’s worth pointing out that creatine supplements aren’t just for bodybuilders, men, or others hoping to improve body composition, muscular strength and power. In fact, creatine may soon be recommended for a variety of neuromuscular disorders (e.g., Huntington’s disease). Parkinson’s patients may also benefit.
For those concerned about diabetes, short-term (i.e., 1 month) creatine supplementation does not seem to negatively affect blood sugar control (glucose tolerance) or insulin action (Newman et al., 2003). Some studies suggest it may actually improve glucose tolerance under certain conditions (see references in Newman et al., 2003).
Lourdes M, Guerrero-Ontiveros, Wallimann T (1998). Creatine supplementation in health and disease. Effects of chronic creatine ingestion in vivo: Down-regulation of the expression of creatine transporter isoforms in skeletal muscle. Mol Cell Biochem, 184: 427.
Newman JEN, Hargreaves M, Garnham A, Snow RJ (2003). Effect of creatine ingestion on glucose tolerance and insulin sensitivity in men. Med Sci Sports Exerc, 35: 1.
Snow RJ, Murphy RM (2001). Creatine and the creatine transporter: A review. Mol Cell Biochem, 224: 169.
Van Loon LJC, Oosterlaar AM, Hartgens F et al. (2003). Effects of creatine loading and prolonged creatine supplementation on body composition, fuel selection, sprint and endurance performance in humans. Clin Sci, 104: 153.
Darkhorse on 04-05-2006, 06:31 PM
LOL, talk about "pissing" away your money.. I'm on a roll!
Darkhorse on 04-19-2006, 02:46 AM
Creatine Ethyl Ester
What is it and where does it come from?
Creatine Ethyl Ester HCL (CEE) is creatine monohydrate with an ester attached. Esters are organic compounds that are formed by esterification - the reaction of carboxylic acid and alcohols.
What does it do and what scientific studies give evidence to support this?
Regular creatine monohydrate has been shown effective at increasing lean muscle mass1,2,3,4, muscle strength5,6 and athletic performance.7,8
However, regular creatine monohydrate is absorbed poorly by the body - and its effectiveness is dependant upon the cells ability to absorb it. The poor absorption rate of regular creatine monohydrate requires the creatine user to ingest large dosages of creatine to achieve desired effect.
Because creatine draws water to the cell, and because most ingested creatine monohydrate is not absorbed, unabsorbed creatine will sit outside of the target cell with the water, and this will result in the "creatine bloat."
Long-term clinical studies have proven that creatine monohydrate is safe for use by persons free of medical complication9, but why would you want to ingest more creatine monohydrate than you have to simply because your creatine is inefficient?
Creatine ethyl ester is creatine monohydrate with an ester attached. The attachment of an ester is significant, because esters are found in the fat tissue of animals. But, why is this important? What role does this have in the absorption of creatine?
All substances that you put into your body will affect its operation. There are three ways that substances can affect a cells operation. They are:
Ligand binding to protein receptor sites.
Secondary messenger / metabotropic systems
Passive permeation of the cell wall via lipids
When a substance enters the body and affects the bodies operation, it is known as a ligand. The soma and dendrites of the cell have protein receptor sites to which ligands can bind. The process of a ligand binding with a receptor site is akin to a lock and key: only keys of a certain shape work with certain locks. When they work and cause the cells stimulation they are called agonists. When they block the cell from functioning they are called antagonists.
When a ligand binds with the receptor site of a target cell, the cell, in the simplest of cases, changes its shape, opens up its ion channels and changes its function. In so-called "secondary messenger" or metabotropic cells, the ligand binds with the receptor site and an internal protein known as a g-protein is released. This released protein then binds to an internal site inside of the cell, and then the cell changes its behavior by opening its ion channels. Cells that operate in this way are known as metabotropic cells because their operation requires metabolic energy.
Passive permeation is a process that describes the diffusion of a substance across a cell membrane through the use of lipids as transport mechanisms. Because no "work" is being done by the cell in this model, this model is called passive permeation.
Creatine monohydrate utilizes lipids to permeate the cell wall and enter the cell. Because of this, the esterification of creatine, and the presence of esters in animal fat tissue, becomes significant.
Creatine monohydrate is semi-lipopholic. This means that it inefficiently uses fat as a transport mechanism. The esterification of substances will increase their lipopholic abilities, and thus esterified creatine will use fat more efficiently to permeate the cell wall and exert its effects upon cellular function than its unesterified creatine monohydrate counterpart.
This means, simply, that not only will dosage requirements be lower, but the absorption of esterified creatine will be increased and the infamous "creatine bloat" will be eliminated!
Who needs it and what are some symptoms of deficiency?
Creatine Ethyl Ester can benefit persons of all ages, as it displays the same benefits as regular creatine monohydrate. Many multiple sclerosis patients are classified as creatine non-responders, but with the improved absorption seen with CEE this may not be the case.
Is Creatine Ethyl Ester real?
Much controversy has been generated over creatine ethyl ester. Companies and individuals with a financial interest in promoting creatine monohydrate products have attempted to discredit creatine ethyl ester. Some companies have even gone so far as to commission laboratory reports that show that creatine ethyl ester is not real.
Included with this page is one such report, and also included are two COA's - certificates of analysis - proving that creatine ethyl ester is real. These are included so that you, the consumer, can make up your own mind - so that you can base your choices upon the power of information.
The one report that states that creatine ethyl ester is fake was commissioned by an industry company with an interest in discrediting creatine ethyl ester. The two certificates of analysis included show that CEE is real and was done on raw source product and conducted by people with no financial interest in the promotion of creatine ethyl ester.
The esterification of creatine is chemically possible and not hard to conceive. Those who claim that CEE is fake are denying obvious science and are cheating the consumer.
How much should be taken? Are there any side effects?
Strictly adhere to label recommendations. No side effects have been reported in scientific literature.
1. Racette SB. Creatine supplementation and athletic performance. J Orthop Sports Phys Ther. 2003 Oct;33(10):615-21.
2. Kreider, R.B., 1999. Dietary supplements and the promotion of muscle growth with resistance exercise. Sports Medicine 27:97-110.
3. Becque, M.D., et al. 2000. Effects of oral creatine supplementation on muscular strength and body composition. Medicine and Science in Sports and Exercise 32: 654-658.
4. Ingwal JS, Weiner CD, Morales MF, Davis E, Stockdale FE: Specificity of creatine in the control of muscle protein synthesis. J Cell Biol 63:145-151, 1974.
5. Rawson ES, Volek JS. Effects of creatine supplementation and resistance training on muscle strength and weightlifting performance. J Strength Cond Res. 2003 Nov;17(4):822-31.
6. Kambis KW, Pizzedaz SK. Short-term creatine supplementation improves maximum quadriceps contraction in women. Int J Sport Nutr Exerc Metab. 2003 Mar;13(1):87-96.
7. Gill ND, Hall RD, Blazevich AJ. Creatine serum is not as effective as creatine powder for improving cycle sprint performance in competitive male team-sport athletes. J Strength Cond Res. 2004 May;18(2):272-5.
8. Rawson, E.S., et al. 1999. Effects of 30 days of creatine ingestion in older men. European Journal of Applied Physiology 80: 139-144.
9. Sosin D.M., Sniezek J.E., Thurman D.J.. Incidence of mild and moderate brain injury in the United States, 1991. Brain Inj 1996 Jan;10(1):47-54.
hrdgain81 on 04-19-2006, 05:23 AM
Correct me if I'm wrong, but I believe i've read that full muscle saturation (of monohydrate) occurs at 3g a day. beyond that you are pissing it away, assuming 3g makes it to the cell interior. So that number should hold true for CEE, you would just need to adjust for absorbtion rates.
EricT on 04-19-2006, 05:35 AM
Yeah, Hardgain, I'm not sure that that part is worded right. I don't think it needs fat as a transport mechanism. The cell wall is lipid, thus lipopholic substances can better permeate the cell wall without active transport mechanisms, I THINK. I don't think it has anything to do with needing fat as a "carrier" like creatine mono needs glucose.
I'm not sure though.
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