A Quick Guide To Creatine

Creatine is one of the most popular supplements among athletes seeking to build muscle mass and improve performance.

A substance that occurs naturally in the body and that is found in many foods, creatine is also marketed in a variety of advanced products often touted as legal steroids. These products come with varying price tags, varying claims of superiority, and with varying recommendations that they be ingested before exercise, after exercise, combined with other supplements, or through loading large quantities in a relatively short amount of time.

While there is significant evidence that creatine taken orally can provide substantial benefit to athletes, research doesn't support some of the more dramatic claims, regimens, or warnings.

What is it, and how does it work?

Creatine is produced in the liver, kidneys and pancreas and stored in muscle tissue. It helps replace  phosphates in the muscles that are lost during exertion through the depletion of ATP (adenosine triphosphate). This phosphate replacement helps produce energy, and creatine's role in this process is its most prominent attribute. 

However, there is evidence that creatine can also promote muscle growth.  A study published in 2000 found that subjects who took 20 grams of creatine a day for five days saw significantly increased fat-free mass and total body mass compared to a placebo, with no changes in body fat [1]. 

While the effect on muscle growth is still the object of considerable study, it is widely believed that the muscle growth occurs partly because the additional  energy creatine produces will allow an athlete to do more work, and partly because creatine causes muscles to hold more water and become volumized through super-hydration.  Additional muscle volume, in turn, not only reduces the breakdown of muscle protein, but it also promotes the synthesis of protein and an increase in the size and strength of muscle fibres [2]. 



How does this translate into results?

Numerous studies have shown creatine can improve athletic performances of short-duration and high-intensity, such as sprinting [3].    However, a Swedish study of creatine use in events requiring sustained exertion concluded that it actually diminished performance among trained endurance runners (researchers speculated that performances may have been diminished among distance runners because of the additional weight gained during their use of creatine) [4].  

A Pennsylvania State University study of creatine use combined with a weight-training program over a 12-week period found significant gains in muscle size and strength compared to exercise alone. Creatine users experienced a 24% strength gain in the bench press, a 32% strength gain doing squats, and double the gain in muscle [5]. 

A Canadian study showed that selected muscles could be bulked up when athletes consume creatine supplements immediately after training.  Thirteen men and 11 women who took part in a six-week resistance training program for arms and legs experienced increases in elbow flexor muscle thickness among those who used creatine supplements that were greater than found among those who took placebos. A similar effect was found in the knee extensors, but it did not reach statistical significance [6]. 



Dosage Protocols

Creatine is found naturally in meats, fish, dairy products, egg whites, nuts and seeds, which may explain why vegetarians – who by definition don't eat meat or fish – usually respond well to supplementation [7].  Vegetarian or not, it is very hard to consume enough food to provide as much creatine as supplementation 

Creatine has been found effective when taken orally, with typical dosages ranging from 3-10 grams per day over an extended period (about 4-5 weeks).  Bodyweight can also be used as a guide to dosage, with ingestion equalling about 0.06 grams per kilogram of weight (0.27g/lb).

An alternative protocol involves an initial loading phase of around 20g of creatine monohydrate each day (4 x 5gram servings during the day) for five days.  This is followed by a maintenance phase in which the dosage is reduced to 3-5g per day.  There is little evidence to show that a loading phase is necessary [13] and lower doses of creatine (3grams per day) over a 30-day period produces the same benefit as loading it over a six-day period [8].  Keep in mind that muscles can store a finite amount of creatine and once this upper limit is reached any excess is flushed out of the body.  

Research indicates that taking creatine with some carbohydrate can increase it's uptake [9].  In the wake of the low-carbohydrate diet craze, research showed that combining creatine with a daily intake of 1,000 grams of lipoic acid also increases creatine uptake. Meanwhile, high doses of caffeine can block the effects of creatine by inhibiting muscle relaxation [10].   



Alternatives To Creatine Monohydrate

Despite commercial manufacturers' claims about the supposed advantages of "effervescent", "micronized" or "ethyl ester" creatine products over regular creatine monohydrate, there is little evidence to support such claims. 

Creatine serum is a more recent addition to the market that makes bold claims.  Sold as "ready-mixed" (as opposed to powdered creatine monohydrate), it's considerably easier to prepare and take.  However, research has questioned both the contents [14,15,16] and effectiveness of this product [17,18].  Not only has Creatine Serum been found to contain very little creatine (and less than was stated on the bottle), it was shown to be ineffective at improving performance.  



Side Effects

Some negative side-effects have been attributed to the use of creatine, such as pulled muscles, cramps, spasms, and increased difficulty in losing fat. However, research has shown that even minor side effects are rare [19] with longer-term studies finding no negative side effects over a period of several years [11,12,20].

As for more serious side effects such as kidney and liver damage, short to long-term studies (up to 5 years) have yet to find any adverse effects from creatine supplementation [12,20,21,22].  However, anyone with existing liver or kidney disease should consult their doctor before taking creatine.



Guidelines For Use

  • Creatine is one of the very few supplements that may be worth experimenting with but it cannot make up for a poor diet and training. 
  • Creatine monohydrate is the most studied and to date, has proven to be the most effective form of creatine.  More elaborate and expensive forms of creatine make bold claims especially about creatine uptake, but may actually be of little or no benefit.
  • Make sure to follow a recommended protocol for taking creatine (such as 20g/day taken in 4 x 5g doses for 5 days followed by 3g/day maintenance for 4-5 weeks). 
  • Creatine uptake can be improved when taken with carbohydrate.  Examples include mixing with cordial and water, drinking fruit juice with it or eating a piece of fruit at the same time.  Creatine often mixes better in hot water (but not boiling water which can damage its structure). 
  • At the end of the loading and maintenance phase (usually about 5-6 weeks in total) it is sensible to have a break from creatine usage.  Take at least 2-4 weeks off from creatine and repeat the protocol or use it as part of the "bulking up" phase of your training plan. 
  • Drink plenty of water throughout the day whilst using creatine and keep alcohol intake to a minimum.
  • Consult your doctor before using creatine if you suffer from any form of kidney or liver disease.

References

1. Mihic, S., MacDonald, J.R., McKenzie, S., & Tarnopolsky, M.A. (2000). Acute creatine loading increase fat-free mass, but does not affect blood pressure, plasma creatinine, or CK activity in men and women. Medicine and Science in Sports and Exercise, 32, 291-296 

2. Haussinger, D. (1996). The role of cellular hydration in the regulation of cell function. Biochemical Journal, 313, 697-710 

3. Volek, J.S., & Kraemer W.J. (1996). Creatine Supplementation: Its effect on human muscular performance and body composition. Journal of Strength and Conditioning Research, 10, 200-210 

4. Balsom, P.D., Harridge, S.D., Soderlund, K., Sjodin, B., Ekblom, B. (1993). Creatine Supplementation Per Se Does Not Enhance Endurance Exercise Performance, Acta Physiologica 

5. Volek J.S., Duncan, N.D., Mazzetti, S.A., Staron, R.S., Putukian, M., Gomez, A.L, Pearson, D.R, Fink, W.J., & Kraemer WJ. (1999). Performance and muscle fiber adaptations to creatine supplementation and heavy resistance training.  Medicine and Science in Sports and Exercise, 31, 1147-1156.

6. Chilibeck, P. D., Stride, D.; Farthing, J.P.; Burke, D. (2004). Effect of Creatine Ingestion after Exercise on Muscle Thickness in Males and Females.  Medicine & Science in Sports & Exercise, 36 (10), 1781-1788.

7. Delanghe, J., De Slypere, J.P., De Buyzere, M., Robbrecht, J., Wieme, R., & Vermeulen, A. (1989). Normal reference values for creatine, creatinine, and carnitine are lower in vegetarians. Clinical Chemistry, 35, 1802-1803. 

8. International Journal of Sports Nutrition and Exercise Metabolism 2000 Sep 10 (3):235-244.

9. Steenge, G.R., Simpson, E.J, & Greenhaff, P.L (2000). Protein-and carbohydrate-induced augmentation of whole body creatine retention in humans. Journal of Applied Physiology, 89, 1165-1171. 92, Issue 2, 513-518.

10. Hespel P, Op `t Eijnde B, Van Leemputte M (2002). Opposite actions of caffeine and creatine on muscle relaxation time in humans. Journal of Applied Physiology, 92 (2), 513-518.

11. Greenwood, M., Kreider, R.B., Melton, C., Rasmussen, C., Lancaster, S., Cantler, E., Milnor, P., & Almada, A. (2003). Creatine supplementation during college football training does not increase the incidence of cramping or injury. Molecular and Cellular Biochemistry, 244, 83-88.

12. Mayhew, D.L., Mayhew, J.L., & Ware, J.S. (2002). Effects of long-term creatine supplementation on liver and kidney functions in American college football players. International Journal of Sport Nutrition and Exercise Metabolism 12, 453-460.

13. Wilder, N., Gilders, R., Hagerman, F., & Deivert, R.G. (2002). The effects of a 10-week, periodized, off-season resistance-training program and creatine supplementation among collegiate football players. Journal of Strength and Conditioning Research, 16, 343-352

14. Almada A, Harris, R.C., Harris, D.B. (2001). Ingestion of creatine serum has no effect on plasma creatine. Journal of the Federation of American Societies for Experimental Biology, 15, LB333A

15. Harris, R.C., Almada, A.L, Harris, D.B., Dunnett, M., & Hespel, P. (2004). The creatine content of Creatine Serum™ and the change in the plasma concentration with ingestion of a single dose. Journal of Sports Sciences, 22, 851-857

16. Dash, A.K., & Sawhney, A. (2002). A simple LC method with UV detection for the analysis of creatine and creatinine and its application to several creatine formulations. Journal of Pharmaceutical and Biomedical Analysis, 29, 939-945

17. Marvar, P.J., Plowman, S.A., Mestek, M.L., Vine, R., & Reimholz, B. (2001). An evaluation of selected claims of liquid creatine. Medicine and Science in Sports and Exercise, 33, S204

18. Gill, N.D., Hall, R.D., & Blazevich, A.J. (2004). Creatine serum is not as effective as creatine powder for improving cycle sprint performance in competitive male team-sport athletes. Journal of Strength and Conditioning Research, 18, 272-275

19. Groeneveld, G.J., Beijer, C., Veldink, J.H., Kalmijn, S., Wokke, J.H.J., & van den Berg, L.H. (2004). Few adverse effects of long-term creatine supplementation in a placebo-controlled trial. International Journal of Sports Medicine, 25

20. Schilling, B.K., Stone, M.H., Utter, A., Kearney, J.T., Johnson, M., Coglianese, R., Smith, L., O'Bryant, H.S., Fry, A.C., Starks, M., Keith, R., & Stone, M.E. (2001). Creatine supplementation and health variables: a retrospective study. Medicine and Science in Sports and Exercise, 33, 183-188 

21. Kreider, R.B., Melton, C., Rasmussen, C.J., Greenwood, M., Lancaster, S., Cantler, E.C., Milnor, P., & Almada, A.L. (2003). Long-term creatine supplementation does not significantly affect clinical markers of health in athletes. Molecular and Cellular Biochemistry, 244, 95-104

22. Poortmans, J.R., & Francaux, M. (2000). Adverse effects of creatine supplementation: fact or fiction? Sports Medicine, 30, 155-170