Creatine Monohydrate Supplementation

Estella Dotson

Answers to Important Questions Concerning Creatine Monohydrate…. and More!

What is creatine monohydrate?

How does it work?

Is it effective?

What is Creatine?

Creatine is a metabolite that is produced naturally by the human body. It is found mainly in the red muscle tissue, but it is also present in the heart and brain. Normally, creatine is acquired through regular dietary intake of products such as meat and fish, which are high in protein. However, when dietary intake is low creatine can be produced from natural amino acids such as glycine, arginine, and methionine in the liver, kidneys, and pancreas. Creatine monohydrate is the synthetic form of creatine (http://creatine-info.com/ - Information on Creatine Monohydrate).

How does creatine work? What is its purpose?

Creatine functions to increase the availability of cellular ATP, adenosine triphosphate. Muscular contractions take place off the presence of ATP and the how quickly it can be regenerated; therefore, an increase in creatine levels is thought to increase the force of muscle contractions (http://www.creatinefacts.com/creatine_monohydrate1.htm). Creatine works by acting on mechanisms of ATP by donating a phosphate ion to increase the availability of ATP. Thus, creatine claims to enhance physical performance by increasing energy and therefore, delaying or minimizing fatigue and adding to the amount of time spent training or working out (http://angelfire.com/co/Creatine/index.html and http://creatine-info.com/ - Information on Creatine Monohydrate).

How much creatine should be taken?

Currently there are no set dosage levels for creatine monohydrate because each person has a maximum level of creatine that cannot be exceeded; therefore, the key to creatine is to benefit from the lowest dosage possible. The most popular dosage regiment has two phases: the loading phase consists of loading the body with creatine to get the levels up. In this phase, 1 heaping teaspoon dose of approximately 5grams is recommended four times daily for one to five days. This is followed by the maintenance phase, which sustains the desired high levels of creatine in the body. The dosage is lowered to 1 teaspoon one to three times a day. The intake of creatine causes the muscle cells to volumize. Basically becoming very hydrated. However, other methods suggest that the loading phase is unnecessary (http://nutrasense.com/nutrasense/creatmon.htm - crdosage). It is also suggested that the most efficient way to maximize low dosages of creatine is to follow the dosage regiment in a cyclical fashion. If creatine levels are allowed to subside and then one takes the supplement, greater results will be seen. In addition, more substantial improvements are likely to be seen in those with a restricted meat diet or those who are vegetarians (http://bodytrends.com/creatine.htm).

Is Creatine effective? What is the evidence?

The effectiveness of creatine monohydrate appears to be relative, depending on one’s diet, how much exercise normally performed, and the duration of exercise normally performed. It appears to be most effective when natural creatine levels are very low. In addition, creatine is mostly for use in intense, short-duration activities such as bodybuilding and weightlifting. It does not appear to be helpful in long duration activities (http://www.betterbodz.com/suppl/bbcreatine.html). The evidence to substantiate the claims of creatine generally comes in the form of testimonies of customers, statistics, and endorsements by professional athletes. Most informational sites do not site specific evidence for the effectiveness of creatine monohydrate. . Many informational sites also attempt to comfort the customer with claims of studies without quoting the procedure or results of the alleged studies. This is most likely linked to the fact that nutritional supplement companies, bodybuilding magazines, exercise and fitness publish most of the sources of information on creatine. In addition, every site began or ended with an advertisement for creatine or other nutritional supplements. Despite all this, physicians at the Mayo Clinic do not believe that there is substantial evidence to prove that creatine or any other nutritional supplement produces effects that can be obtained with proper diet, exercise, and training (http://mayohealth.org/mayo/9811/htm.muscle.htm).

What is the scientific evidence behind creatine?

What is the biological mechanism through which creatine acts?

Creatine acts by altering the availability of cellular ATP. It is produced naturally from amino acids in the liver, kidneys, and the pancreas. From there it is transported to tissues where it can be utilized. As Clarkson and Rawson (1999) note, Creatine exists as free creatine and creatine phosphate. The phosphorylated form makes up approximately 70% of the body’s creatine, and donates its phosphate ion to ADP, which rephosphorylates into ATP, thereby creating energy. Williams and Branch (1998) reveal that creatine monohydrate serves to increase the total muscle creatine amount, both free and phosphorylated forms.

As discussed by Purves et al. (1995), the production of ATP begins with an exergonic reaction, which releases free energy. This allows ADP to combine with a phosphate ion to yield ATP. This in turn makes it possible for ATP to drive an endergonic reaction by breaking down into ADP and a phosphate ion, thus releasing energy in the process. Creatine acts specifically by recycling ADP, adenosine diphosphate, into ATP. Creatine acts by releasing a phosphate for uptake by ADP and conversion to ATP. This serves the purposes of providing more energy expeditiously. It also prevents the body from relying solely on the process of glycolysis, which produces a net of two ATP molecules, but has the byproduct of lactic acid. Lactic acid build up can cause a burning sensation in the muscle and if it reaches high levels it can cause muscle movement to cease (http://angelfire.com/co/Creatine/index.html).

Williams and Branch (1998) also note than creatine monohydrate supplementation has not shown to enhance the functioning in tasks dependent on aerobic glycolysis and suggest that additional research is needed to weigh aerobic metabolic effects of creatine. In addition, Demant and Rhodes (1999) indicate that creatine concentration is greater in fast twitch muscles than in slow twitch muscle fibers, and that slow twitch muscles have an increased ability to resynthesize due to the high aerobic capacity. These two studies together seem to imply that creatine is a largely anaerobic process. However, research remains to be done on this subject.

Does creatine increase muscle mass?

Although creatine is generally used as a supplement for short, intense activity, athletes to increase muscle mass often use it. Many studies and advertisements claim that creatine increases muscle mass; however, Clarkson and Rawson (1999) and Williams and Branch (1998) point out that although there is the possibility of new muscle protein, this gain is most likely due to water retention inside the muscle. As noted by Harris et al., creatine levels did increase following dosages of 20grams for at least two days; however, Clarkson and Rawson (1999) site other experiments that report increases of 1to 3 kilograms in body mass after ingestion of 20-30 grams of creatine for about 5 days. It is also suggests that this increase in muscle mass may be attributable to increased protein or increased water in muscle. Williams and Branch (1998) suggest that chronic supplementation in addition to physical training may increase lean body mass; therefore, accounting for accounts of observed muscle mass increase.

Does dosage alter the effectiveness of creatine?

Research reveals that individual response to creatine varies. For example, those with restricted meat intake or who are vegetarians will see the most dramatic results. As explained by Clarkson and Rawson (1999), vegetarians possess lower levels of serum creatine, which probably indicates low levels of muscle creatine. It is also noted that females posses higher levels of creatine, and older individuals possess less. These results suggest that response to creatine supplementation is relative and depends on how much creatine is in one system prior to ingestion of creatine. In addition, Demant and Rhodes (1999) note that supplementation of 20 grams for three days has resulted in increased levels for some individuals and not others. This suggests the existence of "responders" and "nonresponders" according to the initial total creatine level.

 

 

How does creatine effect performance?

Stout et al. (2000) observed a group of fifteen women on a university crew team using a double-blind random design. Subjects had not ingested creatine or any other supplements for a minimum of 12 weeks before the study, and were asked to abstain from the use of such products for the duration of the study reveal that creatine loading delayed the onset of neuromuscular fatigue. In this study, either a placebo or a creatine beverage was administered to the subjects, after which the subject performed an exercise task. Following the completion of the task, electrodes and EMG’s recorded the levels of creatine in the vastus lateralis muscle of the thigh versus physical working capacity. This was performed and various levels of exercise intensity. Thus, Stout et al. (2000) concluded that creatine delayed the onset of neuromuscular fatigue. The delay could possibly attributed to augmented levels of phosphorylated creatine in the muscle. Casey et al. (1996) proposed that creatine monohydrate increases cellular ATP resynthesis by increasing the availability of phosphorylated creatine, and thus, favorably effects performance.

However, evidence offered by Redondo et al. (1996) suggests that despite increased levels of creatine, performance in a physical task such as sprinting is unaffected. Here eighteen subjects completed two testing sessions, one control and one postsupplement, one week apart. In each trial they sprinted 60 meters and were recorded on film. After the control session, subjects in the treatment group ingested a mixture of creatine and glucose and the placebo group received a glucose powder. Following this, velocities in the 60-meter sprint were measured through three testing zones. Results indicated that there were no statistically significant effects on velocity in a sprint activity following creatine ingestion.

Odland et al. (1997) contradicts the recent studies of Stout et al. In trying to determine the effectiveness of creatine supplementation and short-term power output, Odland et al. (1997) ordered three random tests involving nine males. There was a control group, a creatine monohydrate group and a placebo group. Following ingestion, subjects performed 30 seconds of maximal cycling. Needle biopsies taken from the vastus lateralis before and after exercise revealed no difference in post-exercise blood lactate concentration or percent fatigue. Therefore, findings revealed that a three day dosage of creatine supplementation does not effect performance during a single short-term maximal cycling task.

Does creatine have side effects? How safe is it?

Evidence concerning the physical consequences of creatine usage is virtually nonexistent. Overall, there was a general lack of information regarding effectiveness, and the resources also proved scarce in regards to information surrounding the safety and possible side effects of creatine other than dehydration and muscle cramps. In addition, the Mayo Clinic’s Dr. Laskowski expresses concern over the effects of long term usage of creatine. He suggests that the liver and kidneys are prime targets for risks and side effects of creatine usage (http:// mayohealth.org.mayo/9811/htm.muscle.htm). The issue of product purity was also not addressed in most sites. As noted by Clarkson and Rawson (1999) most manufacturers claim to have the most pure form of creatine, but since nutritional supplements can be marketed without FDA approval there is no guarantee to the customer that the product is pure. The lack of information concerning these critical aspects of creatine usage implies certain irresponsibility on the behalf of the manufactures. The general public looks to manufacturers and the sources of information they disseminate concerning side effects, effectiveness, and product purity. The lie of omission undermines the credibility of many of the claims for creatine.

Conclusion

Overall the effect of creatine monohydrate seems to be minimal. Evidence seems to favor the fact that it suppresses fatigue; however, this is based on the condition that the activity be short in duration and intense. Creatine appears to benefit anaerobic metabolism, fast twitch muscles, as opposed to aerobic, slow twitch muscles provided that the initial levels of creatine for an individual are low. Claims regarding increase in muscle mass are likely linked to retention of water. All of these facts seem to make creatine a supplement that is extremely conditional and variant. The effects seem to be inconsistent and have the potential to vary widely from person to person. Unsubstantiated claims made by manufacturer claiming that creatine is natural also add to the myths surrounding creatine monohydrate.

References:

1. Casey et al. " Creatine ingestion favorably affects performance and muscle metabolism during maximal exercise in humans." American Journal of Physiology 271(1996): E31-7.

2. Clarkson, Patricia, and Eric Rawson. "Nutritional Supplements to Increase Muscle Mass." Critical Reviews in Food Science and Nutrition 39(1999): 317-328.

3. Demant, TW, and EC Rhodes. "Effects of creatine supplementation on exercise performance." Sports Medicine 28(1999): 49-60.

4. Odland, LM, et al. " Effect of oral creatine supplementation on muscle and short term maximum power output." Medical Science Sports Exercise 29(1997): 216-9.

5. Purves, William, Gordon Orians, and Craig Keller. Life: The Science of Biology. Sunderland: Sinauer Associates, Inc., 1995.

6. Redondo, DR, et al. " The effect of oral creatine monohydrate supplementation of running velocity." International Journal of Sports Nutrition 6(1996): 2 13-21.

7. Stout et al. "Effect of creatine loading on neuromuscular fatigue threshold." Journal of American Physiology 88(2000): 109-112.

8. Williams, MH, and JD Branch. " Creatine supplementation and exercise performance: an update." Journal of American College of Nutrition 17(1998): 216-34.

 

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