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Creatine was thought to act simply through a single mechanism of increased intramuscular creatine and phosphocreatine levels, however it is now known that creatine exerts its influence on performance via a number of novel mechanisms. Firstly, creatine has been shown to increase the adaptation to strength training by increasing satellite cell and myonuclei numbers in humans (Olsen et al, 2006) the cell signallers for muscular growth and repair. Secondly, creatine has been shown to act as a cell volumiser; increasing muscle glycogen stores by 18% (van Loon et al, 2004). During glycogen loading phases, supplementation with creatine improves the total muscle glycogen content (Nelson et al, 2001); therefore creatine may also offer a benefit to endurance athletes. Recently creatine has been seen as a more general ergogenic aid, improving cognitive performance (Rae et al, 2003) and as a novel therapeutic aid for a variety of neurodegenerative diseases (Adhihetty & Beal, 2008). Its influence on such a wide range of physiological functions have been attributed to its effects on oxidative metabolism (Ceddia & Sweeney, 2004), maintaining cellular homoeostasis thus reducing oxidative damage eluding to a general antioxidant effect (Lawler et al, 2002.) In terms of dosing and intake Excel Labs suggests a dose of 0.3g per KG of bodyweight for 5 days (for an 80KG male this would be roughly 24g) and then 0.03g per KG of bodyweight (roughly 2.4g for the same 80KG male) daily thereafter. Whilst it has been shown that carbohydrates increate in absorption of creatine, it is also known that small and regular doses of creatine are equally well absorbed, thus though who are intolerable to carbohydrates or are on a low carbohydrate diet may wish to split their doses into smaller and regular dosing or simply go straight into a 0.03g/KGbw dosing regime. References Adhihetty, P.J., & Beal, M.F. (2008). Creatine and its potential therapeutic value for targeting cellular energy impairment in neurodegenerative diseases. Neuromolecular Medicine, 10(4), 272-290.
Bosco, C., Tihanyi, J., Pucspk, J., Kovacs, I., Gobossy, A., Colli, R. et al. (1997). Effect of oral creatine supplementation on jumping and running performance. International Journal of Sports Medicine, 18, 369-372.
Ceddia, R.B., & Sweeney, G. (2005). Creatine Supplementation increases glucose oxidation and AMPK phosphorylation and reduces lactate production in L6 rat skeletal muscle cells. J Physiol, 555(2), 409-421.
Dempsey, R.L., Mazzone, M.F., & Meurer, L.N. (2002). Does oral creatine improve strength? A meta-analysis. J Fam Pract, 11, 945-951.
Earnest, C., Almada, A., & Mitchell, T. (1997). Effects of creatine monohydrate ingestion on intermediate duration anaerobic treadmill running to exhaustion. Journal of Strength and Conditioning Research, 11, 234-238.
Greenhaff, P., Bodin, K., Soderlund, K., & Hultman, E. (1994). Effect of oral creatine supplementation on skeletal muscle phosphocreatine resynthesis. American Journal of Physiology, 266, 725-730.
Harris, R., Soderlund, K., & Hultman, E. (1992). Elevation of creatine in resting and exercised muscle of normal subjects by creatine supplementation. Clinical Science, 83, 367-374. Kreider, R., Ferreira, M., Wilson, M., Grindstaff, P., Plisk, S., Reinhardy, J. et al. (1998). Effects of creatine supplementation on body composition, strength and sprint performance. Medicine & Science in Sports & Exercise, 30, 73-82. Lawler, J.M., Barnes, W.S., Wu, G., Song, W., & Demaree, S. (2002). Direct antioxidant properties of creatine. Biochemical and Biophysical Research Communications, 290(1), 47-52. Nelson, A.G., Arnall, D.A., Kokkonen, J., Day, R., & Evans, J. (2001). Muscle glycogen supercompensation is enhanced by prior creatine supplementation. Med Sci Sports Exerc, 33(7), 1096-1100.
Olsen, S., Aagaard, P., Fawzi, K., et al. (2006). Creatine supplementation augments the increase in satellite cell and myonuclei number in human skeletal muscle induced by strength training. The Journal of Physiology, 573, 52534. Parise, G., Mihic, S., MacLennan, D., Yarasheski, K.E., & Tarnopolsky, M.A. (2001). Effects of acute creatine monohydrate supplementation on leucine kinetics and mixed-muscle protein synthesis. J Appl Physiol, 3, 1041-7. Prevost, M., Nelson, A., & Morris, G. (1997). The effects of creatine supplementation on total work output and metabolism during high-intensity intermittent exercise. Research Quarterly for Exercise and Sport, 68, 233-240. Rae, C., Digney, A., McEwan, S.R., & Bates, T.C. (2003). Oral creatine monohydrate supplementation improves brain performance: a double-blind, placebo-controlled, cross-over trail. Proc Bio Sci, 270, 2147-2150. Van Loon, L.J., Murphy, R., Oosterlaar, A.M., Cameron-Smith, D., Hargreaves, M., Wagenmakers, A.J., & Snow, R. (2004). Creatine supplementation increases glycogen storage but not GLUT-4 expression in human skeletal muscle. Clin Sci (Lond), 106(1), 99-106.
Volek, J., Kraemer, W., Bush, J., Boetes, M., Incledon, T., Clark, K., & Lynch, J. (1997). Creatine supplementation enhances muscular performance during high-intensity resistance exercise. Journal of American Dietetic Association, 97, 765-770. 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. Med Sci Sports Exerc, 8, 1147-56
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