Supplementing with Creatine? Confused with which type to use? How much to use? This review by our in-house Sport Nutritionist Tom Whitehead is aimed at answering the questions and helping you get the most from your supplementation.
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What is Creatine?
Creatine has been one of the most popular “performance enhancing” supplements since it’s introduction in the early 1990’s. Creatine is regularly used by many individuals looking to gain body composition improvements and/or athletic performance, from average gym-goers to world-class elite athletes. It is formed from three amino acids; glycine, arginine and methionine and is classed as a non-essential amino acids, as it can be synthesised in the body from these three amino acids.
95% of the creatine found in the human body is stored in muscle tissue with the remaining 5% found in the brain, liver kidneys and testes (Walker, 1979). Dietary sources of creatine include mainly meats (e.g. beef, fish, pork, chicken, turkey), meaning vegetarians can have a restricted dietary intake.
How does creatine improve exercise performance?
Creatine is obtained through the standard Western diet at roughly 1 g per day for an omnivorous diet.
Creatine and its phosphorylated form, phosphocreatine, are both involved in ATP production through the phosphocreatine energy system (ATP-PC). ATP is the body’s “currency system” and is the body’s energy source; it is involved in most bodily processes, including muscle contraction.
The ATP-PC system is the system used during the first 10-15 seconds of high intensity exercise, during this time ATP is hydrolysed once it has been ‘used’ and forms a relatively low energy ADP. ATP is depleted due to the anaerobic (without oxygen) nature of the exercise, as rate of regeneration cannot mean the rate of depletion. When recovering with an increased availability of oxygen, ATP is regenerated over a period of roughly 3 minutes by phosphocreatine a phosphate group to ADP to create ATP once again. Creatine supplementation increases phosphocreatine stores, which in turn help increase the rate at which ADP can be converted back into ATP, increasing anaerobic capacity and improving ATP recovery.
So many different types of creatine! Which to choose?!
Since the introduction of creatine monohydrate, there have been many attempts to improve the chemical structure to improve certain attributes including solubility in fluids and absorption (bioavailability) and increased performance. These “improved” forms of creatine usually come at a premium price when compared to creatine monohydrate, due to this the “improved” claims and products could be seen as marketing strategies to get you to fork out more of your hard earned cash on products which may not be anymore effective or in certain cases, less effective.
What are the most popular types of creatine?
– Creatine Monohydrate
– Creatine Ethyl Ester
– Creatine Citrate
– Creatine Anhydrous
– Creatine Gluconate
Due to the chemical structure of creatine, it has a low solubility in water. Solubility can be increased by increasing fluid temperature. Heating 1 litre of water has the following effects upon creatine solubility (Jäger et al. 2011);
– 6 g at 4°C
– 14 g at 20°C
– 34 g at 50°C
– 45 g at 60°C
Lower pH solutions can also improve the solubility of creatine in water. Saturated creatine citrate creates a solution with a pH of 3.2 and creatine pyruvate has a pH of 2.6, these two creatine types can hold 19 g per litre and 32.4 g per litre respectively.
– Add creatine to heated ~50°C solutions e.g. a cup of tea to increase solubility possibly aid uptake.
– 5 g creatine will be fully soluble in 250 ml water at 50°C.
Creatine is stable in solid form; research has shown that degradation only starts to occur around 44 months even when stored at 60°C (Jäger, 2003).
However, when added to fluid creatine degrades at a much faster rate. Higher temperatures and lower pH increase degradation. After 3 days of storage different pH levels affected degradation at the following rates; 4% at pH 5.5, 12% at pH 4.5 and 21% at pH 3.5 (Dash et al. 2002 and Harris et al. 1999). Refrigerating the solution has also been shown to reduce degradation (Ganguly et al. 2003).
– If adding creatine to a solution, drink as soon as possible.
– Avoid storing the drink for a prolonged amount of time, if this is required only use creatine monohydrate and not the creatine that creates a lower pH as mentioned previously e.g. creatine pyruvate or creatine citrate and refrigerate.
– Avoid buying ready made beverages containing creatine as these are more than likely useless for creatine consumption.
Creatine Ethyl Ester is one of the more popular creatine supplements and has been claimed to be more superior to creatine monohydrate. However, as creatine ethyl ester has reduced stability in a low pH when compared to creatine, this would appear flawed. Both forms of creatine will have to pass through the stomach, which has a very low pH, increasing the degradation of ethyl ester when compared to monohydrate. Spillane et al. (2009) did find an increase in creatine levels in the body (serum creatinine) following creatine ethyl ester when compared to a placebo at 2, 27 and 48 days. However, this was significantly lower than the increases seen with creatine monohydrate. Providing data to show that creatine monohydrate is superior to creatine ethyl ester despite the claims made.
It appears that many of the “improved” creatine supplements do not have the research data to back up these claims. Many of the research papers mentioned previously have found no improvements and even reductions in measures when compared to creatine monohydrate. Further studies have studied the effects of these creatine supplements of performance but not compared these against creatine monohydrate, so no comparisons can be made. Therefore, currently it would appear that marketing claims and increased prices of certain creatine supplements when compared to the usually cheaper creatine monohydrate are unjust and unsupported.
So now I know which type of creatine to take, how much do I take?
Most of the research on creatine monohydrate follows a standard doseage of loading for 5 days at a dose of 20 g per day (split into 4 x 5 g servings) with a maintenance phase of 5 g per day for 4-8 weeks (Hultman et al. 1996). There appears to be a maximum level of creatine that muscle can store (~160 mmol per kg), this is usually achieved in the loading phase. At these levels a 20 g dose is not required as extra intakes will not increase these creatine stores, hence a maintenance phase of 5 g per day is recommended (Terjung et al., 2000). A dose of 3 g per day over a period of 30 days can also increase muscle creatine levels to those seen in a loading phase (Hultman et al., 1996). Obviously, this will take longer, so a loading phase would be preferred, however, this dose may be useful for weight conscious athletes who would want to avoid the weight increases associated with creatine supplementation (e.g. combat athletes, jockeys and endurance athletes). A 6-week supplementation at 2.3 g per day has been show to significantly increase plasma creatine concentrations and improve resistance to fatigue without increases in weight.
Creatine requires cycling as the body adapts to high creatine levels, and promotes homeostatis after prolonged use, returning to pre-supplementation levels. After 8 week supplementation, take a break for 4-6 weeks before supplementing with creatine again to maximise levels again.
Which Sportskitchen Plan should I take Creatine with?
Perform Low Carb
– Creatine can help maintain lean muscle whilst reducing body weight.
– Doses of 2-3 g per day without a loading phase will prevent weight gain if conscious of weight.
– Ideal for athletes involved in sports with an intermittent, high intensity or team sport nature and those looking to maintain weight, whilst looking for strength gains.
– Creatine does not improve endurance performance.
– However, it may help the anaerobic “final kick” towards the end of an endurance race.
– Smaller doses of 2-3 g per day may be suitable for endurance athletes as this is not associated with weight gain seen with higher doses.
– May also help increase glycogen stores if used during carbohydrate loading more so than not using creatine
Side Effects of Creatine
Despite the claims of reduced kidney and liver function, the only side effect regularly reported is weight gain. This is usually 1-2 kg within the first loading week, due to an increase in water retention.
Although creatine has been linked with reduced renal function there have been no studies supporting this claim (Persky and Brazeau, 2001). In one study, subjects self-supplemented with 2-30 g creatine per day for 10 months to 5 years without any renal responses observed (Poortmans et al., 1997).
In healthy individuals creatine appears to be a safe ergogenic aid (Bizzarini and De Angelis, 2004).
– When loading split into 4 x 5 g servings per day and maintain for up to 8 weeks with 5 g per day.
– Doses of 2-3 g per day without a loading phase will prevent weight gain if conscious of weight.
– Add to hot beverages and consume with meals to maximize absorption.
– Drink as soon as possible after adding to fluid.
– Creatine has no clinical side effects and is safe to use in recommended doses.
– Creatine monohydrate appears to be a safe ergonomic aid.
– Finally…. Don’t listen to the marketing hype, save your money and buy creatine monohydrate!
Bizzarini, E. and De Angelis, L. (2004).Is the use of oral creatine supplementation safe?The Journal of Sports Medicine and Physical Fitness, 44(4), 411-416.
Ganguly, S., Jayappa, S., and Dash, A. K. (2003). Evaluation of the stability of creatine in solution prepared from effervescent creatine formulations. AAPS PharmSciTech, 4 (2), E25.
Harris, R. C., Soderland, K. and Hultman, E. (1992) Elevation of creatine in resting and exercised muscle of normal subjects by creatine supplementation. Clin. Sci 83: 367-374.
Hultman, E., Söderlund, K., Timmons, J. A., Cederblad, G., Greenhaff, P. A. (1996) Muscle creatine loading in men. Journal of Applied Physiology, 81, 232–237.
Jäger, R. (2003). The use of creatine monohydrate in sports nutrition, Freising, Germany
Jäger, R., Purpura, M., Shoa, A., Inoue and T., Kreider, R. B. (2011). Analysis of the efficacy, safety, and regulatory status of novel forms of creatine. Amino Acids, 40, 1369-1383.
Persky, A. M. and Brazeau, G. A. (2001). Clinical Pharmacology of the Dietary Supplement Creatine Monohydrate. Pharmacological Reviews, 53 (2), 161-176.
Poortmans, J. R., and Francaux, M. (1999) Long-term oral creatine supplementation does not impair renal function in healthy athletes. Medicine and Science in Sports and Exercise, 31, 1108–1110.
Spillane, M., Schoch, R., Cooke, M., Harvey, T., Greenwood, M., Kreider, R. and Willoughby, D. S. (2009). The effects of creatine ethyl ester supplementation combined with heavy resistance training on body composition, muscle performance, and serum and muscle creatine levels. Journal of the International Society of Sports Nutrition, 6, 6.
Terjung, R. L., Clarkson, P., Eichner, E. R., Greenhaff, P. L., Hespel, P. J., Israel, R. G, Kraemer, W. J., Meyer, R. A., Spriet, L. L., Tarnopolsky, M. A., Wagenmakers, A. J. and Williams, M. H. (2000). American College of Sports Medicine roundtable. The phy.siological and health effects of oral creatine supplementation. Medicine and Science in Sports and Exercise, 32, 706–717.
Walker, J. (1979). Creatine: Biosynthesis, regulation, and function. Advance Enzymes in Human Nutrition, 50, 117–242.