I say, no way.
I've posted an abstract of this study before, but I just found access to the entire study.
Here's a case study which indicated that daily creatine supplementation was not needed to maintain skeletal muscle PCr saturation during a 30-day washout.... yes, 30-days. The study was repeated twice.
What was even more impressive, was that PCr levels increased 45% after the first bout (20-g for 5-days), and only 22% of that increase was lost out of a 30-day time-frame.... that's still 23% higher than the pre-supplementational values. This would suggest that daily creatine supplementation appears to only keep serum levels from being depleted.
If PCr levels remain elevated from creatine supplementation for a significant duration of time, even when not supplementing creatine.... then I strongly feel that creatine can easily be ingested on workout days only, without any depletion of skeletal muscle PCr whatsoever.
EFFECTS OF REPEATED CREATINE SUPPLEMENTATION ON MUSCLE, PLASMA, AND URINE CREATINE LEVELS
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06-22-2007, 06:24 PM #1
Is there truly a need for daily creatine supplementation?
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Wherever progression lacks.... regress can be found in abundance.
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06-22-2007, 06:28 PM #2
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06-22-2007, 06:42 PM #3
I think supplemental creatine sucks.... but that's probably just do to my fast-twitch muscle fibers. Overall though, I think that more people should stop and re-evaluate the reasonings behind it's daily administration.
I also firmly believe that creatine's daily supplementation will result in the downregulation of the creatine transporter, and this would basically nullify the entire reasoning behind it's supplementation.~
Wherever progression lacks.... regress can be found in abundance.
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06-22-2007, 06:47 PM #4
I liked creatine when I was on it. Wicked strength gains. I hated creatine when I was off it. Wicked strength loss. All in all, creatine isn't for me, I'll do without =]
"You know you're a bodybuilder when people ask you what day it is and you reply with a muscle group"
Short term goals:
1.) Weighted Dips 45lbs. x ?
2.) EZ Bar Curl 100lbs. x ?
3.) DB Bench Press 80s x ?
Long term goals:
1.) Hit 190 and stay lean.
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06-22-2007, 07:07 PM #5
- Join Date: Sep 2006
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i am not sure i buy the down regulation...but who knows. From time to time i get tired of taking it though....but i honestly do not notice a big diff between being on and off, its pretty slight for me, but i figure if i am going to spend money i am best off doing it on something that actually has real science to back it.
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06-22-2007, 07:23 PM #6
The downregulation of the creatine transporter (CreaT) as a result of excessive creatine supplementation, has indeed been proven to be an evident fact.... it's just that no studies have evaluated this in healthy adults.
I too never noticed much of a difference.... hence the reason I stopped wasting my money.Last edited by NO HYPE; 06-23-2007 at 03:31 AM.
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Wherever progression lacks.... regress can be found in abundance.
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06-22-2007, 07:40 PM #7
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06-22-2007, 07:58 PM #8
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06-22-2007, 08:02 PM #9
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06-22-2007, 08:10 PM #10
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06-22-2007, 08:19 PM #11
More: http://forum.bodybuilding.com/showth...1#post53207561
few posts down des posted transporter downregulation citation
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06-22-2007, 08:27 PM #12
The evidence is interesting to say the least (I presented that study to des). Even though the evidence within this study (as well as others) is inconclusive, it should make people think twice about supplementing creatine every day.
IMO.... CreaT downregulation, likely applies to healthy individuals as well.Last edited by NO HYPE; 06-23-2007 at 03:32 AM.
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Wherever progression lacks.... regress can be found in abundance.
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06-22-2007, 08:39 PM #13
Yeah I saw you posted in that thread now.
I wish I could open pdfs on this computer
Could be a reason there are so many non responders. Maybe they just need a lower dose (and most probably keep raising dose if they don't feel anything).
There had to be a negative feedback somewhere. I wonder what long term implications of this downregulation are. Could be very bad news, phosphocreatine depletion in the brain, for instance, is linked to depression I believe.
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06-22-2007, 08:47 PM #14
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06-22-2007, 08:48 PM #15
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06-22-2007, 08:53 PM #16
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06-22-2007, 08:59 PM #17
It seems that dietary creatine is necessary for "normal" endogenous levels:
1: Med Sci Sports Exerc. 2003 Nov;35(11):1946-55. Related Articles, Links
Click here to read
Effect of creatine and weight training on muscle creatine and performance in vegetarians.
Burke DG, Chilibeck PD, Parise G, Candow DG, Mahoney D, Tarnopolsky M.
Department of Human Kinetics, St. Francis Xavier University, Antigonish, Nova Scotia, Canada. dburke@stfx.ca
PURPOSE: To compare the change in muscle creatine, fiber morphology, body composition, hydration status, and exercise performance between vegetarians and nonvegetarians with 8 wk of creatine supplementation and resistance training. METHODS: Eighteen VG and 24 NV subjects (19-55 yr) were randomly assigned (double blind) to four groups: VG + creatine (VGCr, N=10), VG + placebo (VGPl, N=8), NV + creatine (NVCr, N=12), and NV + placebo (NVPl, N=12). Before and at the end of the study, muscle biopsies were taken from the vastus lateralis m, body composition was assessed by DXA, and strength was assessed using 1-RM bench press and leg press. Subjects participated in the same 8-wk resistance-training program. Creatine dosage was based on lean tissue mass (0.25 g.kg(-1) LTM.d(-1) x 7 d; 0.0625 g.kg(-1) LTM.d(-1) x 49 d). RESULTS: Biopsy samples indicated that total creatine (TCr=free Cr + PCr) was significantly lower in VG compared with NV at baseline (VG=117 mmol.kg(-1); NV=130 mmol.kg(-1); P<0.05). For Cr subjects, there was a greater increase in PCr, TCr, bench-press strength, isokinetic work, Type II fiber area, and whole-body lean tissue compared with subjects on placebo (P<0.05). Vegetarians who took Cr had a greater increase in TCr, PCr, lean tissue, and total work performance than nonvegetarians who took Cr (P<0.05). The change in muscle TCr was significantly correlated with initial muscle TCr, and the change in lean tissue mass and exercise performance. These findings confirm an ergogenic effect of Cr during resistance training and suggest that subjects with initially low levels of intramuscular Cr (vegetarians) are more responsive to supplementation.
Publication Types:
* Clinical Trial
* Randomized Controlled Trial
* Research Support, Non-U.S. Gov't
PMID: 14600563 [PubMed - indexed for MEDLINE]
EDIT: Didn't make my point obvious here to those who might be lost, I am wondering to what extent supplementing creatine daily at normal to high levels longterm would downregulate transporter and what would happen after stopping supplementation, transporter downregulation could stop normal dietary absorption and result in lower endogenous levels. To what extent? Who knows.Last edited by fitnecise; 06-22-2007 at 09:05 PM.
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06-22-2007, 09:15 PM #18
We can't forget AGAT or GATM, either, involved in creatine synthesis and are downregulated with supplementation:
http://jap.physiology.org/cgi/content/full/97/3/852
This is interesting:
In summary, the present results for the first time confirm in humans that oral creatine supplementation in doses of 5–20 g/day is related to a reduction in circulating GAA levels, suggesting that endogenous creatine synthesis is chronically (up to 5 mo) suppressed at the level of the transamidinase reaction catalyzed by AGAT. Additionally, these data suggest that creatine biosynthesis repression leads to enhanced utilization of arginine as a substrate for secondary guanidino compound pathways.Last edited by fitnecise; 06-22-2007 at 09:19 PM.
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06-22-2007, 09:28 PM #19
Another important note from that study ^
Analogy with animal studies would suggest that the latter phenomenon is predominant because reduction of AGAT activity is observed not within hours but only within days after the start of creatine supplementation (9). Therefore, future studies will have to determine the exact time course of downregulation of creatine biosynthesis in humans. The creatine supplementation regimen employed in the present study (1-wk loading phase with 20 g/day and a subsequent maintenance dose of 5 g/day) is routinely used by athletes and patients, on the basis of scientific evidence (13, 27). We now suggest that such creatine supplementation regimen downregulates endogenous creatine biosynthesis within 1 wk and as long as supplementation is continued.Last edited by fitnecise; 06-22-2007 at 09:33 PM.
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06-22-2007, 09:37 PM #20
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06-22-2007, 09:39 PM #21
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06-22-2007, 09:43 PM #22
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06-22-2007, 10:56 PM #23
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06-22-2007, 11:07 PM #24
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06-23-2007, 02:15 AM #25
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06-23-2007, 02:49 AM #26
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06-23-2007, 04:13 AM #27
Tyrosine phosphorylation of the creatine transporter?
Here's a study on creatine transporter expression/downregulation in response to creatine supplementation in animals during sepsis. I wonder if tyrosine phosphorylation of the creatine transporter can be a factor in sepsis-free subjects?
"Thus, on the basis of the results presented in the current study and the data available in the literature, it is reasonable to hypothesize that extracellular Cr must be transported into the cells where accumulated Cr feedback inhibits c-Src-related tyrosine phosphorylation of the CreaT. Although the mechanism(s) by which the downregulatory effects on c-Src-related tyrosine phosphorylation of the CreaT after dietary Cr supplementation occur is unknown, we speculate that preaccumulation of intracellular Cr in muscle after oral Cr supplementation may cause acquired intrinsic alteration(s) in the control of myocellular energy metabolism that may trigger changes in intracellular signaling pathways by which the downregulatory effects on c-Src-related tyrosine phosphorylation of the CreaT after Cr supplementation occurs in skeletal muscle during sepsis. These remain to be defined and are the subjects of future investigations."
"Although the physiological relevance of Cr supplementation's downregulatory effects on tyrosine phosphorylation of the CreaT during sepsis is not yet clear, it is obvious that myocellular CreaT function is tightly regulated and involves c-Src-related tyrosine phosphorylation during sepsis."
http://ajpendo.physiology.org/cgi/re...046.pdf?ck=nckLast edited by NO HYPE; 06-23-2007 at 04:30 AM.
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Wherever progression lacks.... regress can be found in abundance.
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06-23-2007, 08:26 AM #28
1) The Science Section revival is so nice to see..lets keep it going
2) I 100% agree with NO HYPE here, somewhere in this section I have a thread called "Creatine - are we taking too much", Its been ages since its been up front but I know I referenced the 30 day washout period, and saw no reason that taking 3-5g post workout, 3-4 times a week is likely plenty to max out our storage levels.
Good thread NO HYPE.
Edit - http://forum.bodybuilding.com/showthread.php?t=680102Last edited by Skigazzi; 06-23-2007 at 08:28 AM.
The Dark Knight...Rises.
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06-23-2007, 01:23 PM #29
I didn't see this before, Dr. Tallon wrote an article on this subject:
http://www.bodybuilding.com/fun/tallon2.htm
I also vaguely remember a study on "long" term creatine supplementation and possible increased storage ability, but maybe it wasn't on humans. I'll see if I can find it.
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06-23-2007, 01:32 PM #30
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