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2005/10/06, 09:43 AM
I'm just posting this as info and not argument. As always, there are plenty of question about creatine. I've read several posts in the past couple of weeks where people are posting their opinions as fact. My own "opinion" documented in my training logs says it works for me and very effectively. I also know of many posters on FT that keep training journals that will state the same thing. I've also read some posts saying there is no scientific evidence that it works and had to laugh at those. If you don't think it works, don't take it. Creatine is without doubt the most studied supplement in the history of supplements. Below is a few of the hundreds of relevant studies along with a synopsis in case anyone is interested.
Major Research Reviews Include: Gastelu, D, "Creatine Research Update 2005", Supplementfacts International LLC, 2005. Greeenhaff, PL. The nutritional biochemistry of creatine. J Nutr Biochem 1997;8:610-618. Juhn, MS and Tarnopolsky, M. Oral creatine supplementation and athletic performance: A critical review. Clin J Sport Med 1998;8:286-297. Kreider, RB, Leutholtz, BC and Greenwood, M. Creatine. In Nutritional Ergogenic Aids, CRC Press 2004:81-104. Lemon PW. Dietary creatine supplementation and exercise performance: why inconsistent results? Can J Appl Physiol. 2002 Dec;27(6):663-81. Persky, AM and Gayle, AB. Clinical pharmacology of the dietary supplement creatine monohydrate. Pharmacological Reviews. 2001;53:161-176. Turpin, AA, et al. Systematic and critical evaluation of benefits and possible risks of nutritional ergogenic aids. In Nutritional Ergogenic Aids, CRC Press 2004:469-504 Walker, JB. Creatine: biosynthesis, regulation and function. Adv Enzymol Relat Areas Mol Biol 1979;50:177-242 Williams, MH and Branch, JD. Creatine supplementation and exercise performance: An update. Journal of the American College of Nutrition 1998;17(3):216-234.
Deldicque L, Louis M, Theisen D, Nielens H, Dehoux M, Thissen JP, Rennie MJ, Francaux M.
"Increased IGF mRNA in human skeletal muscle after creatine supplementation."
Med Sci Sports Exerc. 2005 May;37(5):731-6.
Comparing the results of an experimental group (creatine takers) to the results of a placebo taking group allows the researchers to determine if there are any beneficial effects from taking creatine supplements. In over 85% of the more then 200 clinical studies using creatine monohydrate, significant beneficial effects were observed in the creatine taking groups of individuals.
In most of the studies where a significant effect was not observed, this was primarily due to inadequate creatine intake (studies testing the lower range of beneficial intake), or athletes not expected to benefit from taking creatine, such as long-distance endurance athletes. Studies that did not find a significant improvement, did not report a negative effect from creatine use, in other words, creatine either produced either significantly beneficial effects, or neutral effects.
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Mike
in Pensacola Now.
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2005/10/06, 01:03 PM
To add to that....2 nice studies....
Med Sci Sports Exerc. 2005 May;37(5):731-6. Related Articles, Links
Increased IGF mRNA in human skeletal muscle after creatine supplementation.
Deldicque L, Louis M, Theisen D, Nielens H, Dehoux M, Thissen JP, Rennie MJ, Francaux M.
Department of Physical Education and Rehabilitation, Faculty of Medicine, Catholic University of Louvain, Louvain-la-Neuve, Belgium.
PURPOSE: We hypothesized that creatine supplementation would facilitate muscle anabolism by increasing the expression of growth factors and the phosphorylation of anabolic signaling molecules; we therefore tested the responses of mRNA for IGF-I and IGF-II and the phosphorylation state of components of anabolic signaling pathways p70(s6k) and 4E-BP1 to a bout of high-intensity resistance exercise after 5 d of creatine supplementation. METHODS: In a double-blind cross-over design, muscle biopsies were taken from the m. vastus lateralis at rest and 3 and 24 h postexercise in subjects who had taken creatine or placebo for 5 d (21 g x d(-1)). For the first 3 h postexercise, the subjects were fed with a drink containing maltodextrin (0.3 g x kg(-1) body weight x h(-1)) and protein (0.08 g x kg(-1) body weight x h(-1)). RESULTS: After creatine supplementation, resting muscle expressed more mRNA for IGF-I (+30%, P < 0.05) and IGF-II (+40%, P = 0.054). Exercise caused an increase by 3 h postexercise in IGF-I (+24%, P < 0.05) and IGF-II (+48%, P < 0.05) and by 24 h postexercise in IGF-I (+29%, P < 0.05), but this effect was not potentiated by creatine supplementation. The phosphorylation states of p70(s6k) and 4E-BP1 were not affected by creatine at rest; phosphorylation of both increased (150-400%, P < 0.05) to similar levels under placebo and creatine conditions at 3 h postexercise plus feeding. However, the phosphorylation state of 4E-BP1 was higher in the creatine versus placebo condition at 24 h postexercise. CONCLUSION: The increase in lean body mass often reported after creatine supplementation could be mediated by signaling pathway(s) involving IGF and 4E-BP1.
And, from the same guy who helped design the above study.....a follow up
Metabolism. 2001 Dec;50(12):1429-34. Related Articles, Links
Comparison of creatine ingestion and resistance training on energy expenditure and limb blood flow.
Arciero PJ, Hannibal NS 3rd, Nindl BC, Gentile CL, Hamed J, Vukovich MD.
Exercise Science Department, Skidmore College, Saratoga Springs, NY, USA.
This study determined the effects of 28 days of oral creatine ingestion (days 1 to 5 = 20g/d; : days 6 to 28 = 10 g/d; ) alone and with resistance training (5 hours/week) on resting metabolic rate (RMR), body composition, muscular strength (1RM), and limb blood flow (LBF). Using a double-blind, placebo-controlled design, 30 healthy male volunteers (21 +/- 3 years; 18 to 30 years) were randomly assigned to 1 of 3 groups; pure creatine monohydrate alone (Cr; n = 10), creatine plus resistance training (Cr-RT; n = 10), or placebo plus resistance training (P-RT; n = 10). Body composition (DEXA, Lunar DPX-IQ), body mass, bench, and leg press 1RM (isotonic), RMR (indirect calorimetry; ventilated hood), and forearm and calf LBF (venous occlusive plethysmography) were obtained on all 30 subjects on 3 occasions beginning at approximately 6:00 AM following an overnight fast and 24 hours removed from the last training session; baseline (day 0), and 7 days and 29 days following the interventions. No differences existed among groups at baseline for any of the variables measured. Following the 28-day interventions, body mass (Cr, 73.9 +/- 11.5 v 75.6 +/- 12.5 kg; Cr-RT, 78.8 +/- 6.7 v 80.8 +/- 6.8 kg; P <.01) and total body water (Cr, 40.4 +/- 6.8 v 42.6 +/- 7.2 L, 5.5%; Cr-RT, 40.6 +/- 2.4 v 42.3 +/- 2.2 L, 4.3%; P <.01) increased significantly in Cr and Cr-RT, but remained unchanged in P-RT, whereas, fat-free mass (FFM) increased significantly in Cr-RT (63 +/- 2.8 v 64.7 +/- 3.6 kg; P <.01) and showed a tendency to increase in Cr (58.1 +/- 8.1 v 59 +/- 8.8 kg; P =.07). Following the 28-day period, all groups significantly increased (P <.01) bench (Cr, 77.3 +/- 4 v 83.2 +/- 3.6 kg; Cr-RT, 76.8 +/- 4.5 v 90.5 +/- 4.5 kg; P-RT, 76.0 +/- 3.4 v 85.5 +/- 3.2 kg), and leg press (Cr, 205.5 +/- 14.5 v 238.6 +/- 13.2 kg; Cr-RT, 167.7 +/- 13.2 v 238.6 +/- 17.3 kg; P-RT, 200.5 +/- 9.5 v 255 +/- 13.2 kg) 1RM muscular strength. However, Cr-RT improved significantly more (P <.05) on the leg press 1RM than Cr and P-RT and the bench press 1RM than Cr (P <.01). Calf (30%) and forearm (38%) LBF increased significantly (P <.05) in the Cr-RT, but remained unchanged in the Cr and P-RT groups following the supplementation period. RMR expressed on an absolute basis was increased in the Cr (1,860.1 +/- 164.9 v 1,907 +/- 173.4 kcal/d, 2.5%; P <.05) and Cr-RT (1,971.4 +/- 171.8 v 2,085.7 +/- 183.6 kcal/d, 5%; P <.05), but remained unchanged from baseline in P-RT. Total cholesterol decreased significantly in Cr-RT (-9.9%; 172 +/- 27 v 155 +/- 26 mg/dL; P <.01) compared with Cr (174 +/- 46 v 178 +/- 43 mg/dL) and P-RT (162 +/- 32 v 161 +/- 36 mg/dL) following the 28-day intervention. These findings suggest that the addition of creatine supplementation to resistance training significantly increases total and fat-free body mass, muscular strength, peripheral blood flow, and resting energy expenditure and improves blood cholesterol. Copyright 2001 by W.B. Saunders Company
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If you don't stand for something, you will fall for anything....
bb1fit@freetrainers.com
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