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 La créatine

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MessageSujet: Re: La créatine   Sam 17 Avr - 4:15

les 2

je doute que mes avis divergent , au contraire
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VII

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MessageSujet: Re: La créatine   Sam 17 Avr - 11:52

Je pense pas non. En tout cas, je suis d'accord avec ce que Crom disait au-dessus.
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BOBI

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MessageSujet: Re: La créatine   Sam 17 Avr - 15:27

Ben je dit ça parce que Crom dit que le jus de raisin c'est de la couille en barre,alors que tt le monde dit que c'est le "must" et que les effets viennent quasi au bout d'1 mois, alors que d'autres disent 8/10 jours.

T'façon du jus de raisin j'en ai pas... Pis pour les effets ben je verrai si ça vient
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rom1ch

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MessageSujet: Re: La créatine   Jeu 13 Mai - 17:14

quelle sont les differante sorte de creatine existe il?
quel sont les benefices l'ors d'un antreinemant
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umag

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MessageSujet: Re: La créatine   Jeu 13 Mai - 17:24

Salut tout le monde

Je remonte ce topic, car je pense qu'il y a encore à dire. Certains me connaissent en "vrai" et savent que je travaillent dans le bussiness de tous ces petits produits.

Mon but c'est de pas faire de pub, c'est juste pour avoir des avis, vu que sur certains nouveaux poduits sa manquent d'expériences sérieuses. J'ai la chance de tester les produits (vu que j'ai des prix) lors de mes entrainements (8 ans de training):

- la krea: Qui a essayé avec des doses intéressantes? Souvent les fabricants proposent des cures de 3 gr par jour, perso je trouve que c'est peu, je préfére monter à 6 gr.

-Produits à base de créatine ethyl ester: même tendance, j'ai tourner avec 5 à 7 gr.

C'est sur que le problème c'est que tester ces produits, sa fait un budget lol.

Pour l'isntant, sur mon expérience perso, les produits avec de la créa ethyl ester, c'est le mieu, la créa mono avec le label créapure, bien. Enfin, kréa comme je disai bien pour moi mais en doublant les doses recommandées.
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umag

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MessageSujet: Re: La créatine   Sam 15 Mai - 13:57

Salut

Un petit lien sur krea

http://www.toutelacreatine.com/articles/creatine-kre-alkalyn-halterophiles.php

Quand on cherche un peu sur le web, on se rend compte d'une chose: On lit de tout!
Un article va dire si, un autre sa.

Au jour d'aujourd'hui, le manque de recul et de multiples expériences ne permettent pas de tirer de conclusion claire.

En gros toujours au même point: Essayer les différentes formes pour voire ce qui marche pour soit.

Ce qui est quand même fou, c'est de tels écarts entre les expériences: Par exemple, Certains disent pas de créatinine avec le krea, d'autres disent plus de créatinine avec la krea par rapport à la mono. Comment savoir qu'lelle est l'expérience qui craint!
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rom1ch

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MessageSujet: Re: La créatine   Sam 15 Mai - 19:29

merci UMAG pour le lien, epopu tes informations
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Bodytrainever

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MessageSujet: Re: La créatine   Sam 3 Juil - 15:20

Un petit ajout dans tout cela concernant l'ATP (adénosine tri-phosphate) je pense que c'est important de le savoir, donc l'adénosine tri-phosphate correspond à la molécule fournissant l'énergie aux cellules nécessaire durant l'effort. L'adénosine tri-phosphate est composée d'adénine, de ribose et de trois ions phosphate (d'où son nom lol). Lorsque l'ATP est mobilisée pour fournir de l'énergie aux cellules celle-ci perd un ion phosphate ce qui libère 10 calories d'énergie, l'ATP devient alors de L'ADP (adénosine di-phosphate) puisqu'elle ne contient à présent plus que deux ions phosphate.Comme il à était dit précédemment la créatine est stockée dans les muscles sous forme de créatine phosphate, ce phosphate va permettre a l'ADP de pouvoir re-synthétiser des molécules d'ATP (puisqu'il suffit qu'elle récupère un ion phosphate pour retrouver sa forme "de base" ATP (la source d'énergie)).
Quant-à la ribose elle permet d'accélérer la reconstitution des stocks d'ATP après un effort il est donc intéressant d'avoir une supplémentation en ribose et en créatine .

Voilà petite parenthèse j'espère avoir était claire et pas trop ennuyeux pour ceux que sa intéresse ^^. Very Happy
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umag

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MessageSujet: Re: La créatine   Sam 3 Juil - 18:43

Ribose a testé: manque d'étude sur la façon optimale d'en prendre et très variable selon les personnes.
La méthode la plus courante c'est une prise avant training en augmentant progressivement les doses pour voire comment on réagi.
a voire
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MetzgerMeister

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MessageSujet: Re: La créatine   Sam 4 Sep - 17:02

Donc petite question sur la créa:

Etant composée de trois acides aminés, une suralimentation en protéine ne comble-t-elle pas déjà les besoins pour la synthèse de nouvelle créatine plutôt qu'une supplémentation directe ?
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MessageSujet: Re: La créatine   Sam 4 Sep - 17:14

Non ce n'est malheureusement pas aussi simple

Pour t'en rendre compte il suffit de regarder l'effet que peut avoir une prise de créa sur des cultos wannabe qui avaient pratiquement tous une surconsommation systématique de prot au préalable
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DBS

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MessageSujet: Re: La créatine   Sam 4 Sep - 17:16

Crom a écrit:
les cultos wannabe

spit Laughing
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MetzgerMeister

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MessageSujet: Re: La créatine   Sam 4 Sep - 17:16

D'accord Wink

C'est vrai que j'ai souvent tendance à penser à des théories trop simplistes, mais je me dis qu'on sait jamais ^^'

Merci yep
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Screwdat



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MessageSujet: Re: La créatine   Sam 4 Sep - 17:19

Tu fais très bien d'y penser

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vlad

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MessageSujet: Re: La créatine   Dim 17 Oct - 17:56

Moi je vais vous faire par de mon experience

j ai eu pris de la creatine alkalyn qui en fait est de la monohydrate a ph basique et c est pour cela qu elle est censer d apres les dire ne pas fabriquer de la creatinine et quelle s assimile beaucoup mieux que la monohydrate pur( ceci reste tout de meme a prouver)

mon meilleur ami et moi avons essayer en meme temps la creatine AKG
qui est plus assimilable toujours d apres des dires
resultat au bout d une semaine
moi j avais des nausee toute la journee, mon meilleur ami qui avez a la base des brulure d estomac qu il n avait pas eut depuis 2 ans en a eut au bout de trois jour de prise et biensur aucun resultat sur la force .
Apres quelque recherche sur le net j ai lu que la creatine AKG pour quelle reste stable dans l organisme et plus facilement assimilable faisait produire plus de suc digestif dans l estomac donc plus d acidite d ou le retour des brulure d estomac de mon ami.

BREF a la fin de la semaine on a repris de l alkalyn et franchement plus de brulure ,pluss de nausee et surtout au bout de 3 jours de prise une peche d enfer a l entrainement une progression dans les charges biensur pas dementiel mais plus d intensiter et moins de temps de repos entre les series et finalement 2 kilos en plus sur la balance en 2 semaines .

je pense que la kre alacalyn me reussit bien et surtout qu elle ne me rend pas malade mais attention je tiens a preciser que ceux qui a marcher sur moi ne marchera pas forcement sur un autre.
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thejpman

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MessageSujet: Re: La créatine   Jeu 4 Nov - 4:14



Creatine: Energy Currency, Enigma, and Magic Bullet
Written by Roddy O' Connor, Ph.D.
Wednesday, 03 November 2010 18:14


Capturing the imagination since its inception as a collaborative factor in muscle growth, creatine remains the quintessential hot topic in muscle physiology. If there were a continuum of sentiment on the ergogenic potential of supplements, creatine would lie favorably at the leading edge. A large body of work confirms that creatine is indispensable for muscular performance during repeated sets of intense exercise. Of interest, recent studies have provided insight into the versatility of creatine; shifting the paradigm towards satellite cell dynamics.


Creatine: Mechanism of Action

Skeletal muscle fibers are enriched with proteins (actin and myosin), that require energy to generate force during muscle contraction. The universal energy currency for all cells, ATP, is generated by oxidative phosphorylation in subcellular compartments known as mitochondria. Given that these contractile proteins are distributed throughout the myofiber, and ATP diffuses poorly from its origin in the mitochondria; the energy potential of ATP is transferred to an alternate molecule: creatine. In contrast to ATP, phosphocreatine (PCr) readily diffuses throughout the cell due to favorable physiochemical properties.



A number of studies support the biologic tenet that phosphocreatine replenishes ATP levels during repeated sets of intense physical activity. As muscular contraction is dependent on ATP, these findings suggest that increasing the availability of PCr may result in higher levels of force production during repeated sets of resistance training. In addition, raising intramuscular creatine levels would enhance the kinetics of ATP replenishment during recovery between sets. Importantly, achieving those final repetitions on the third and fourth set of a resistance exercise is associated with enhanced muscular adaptation, and moreover, concordant with the fundamental philosophy of progressive resistance training. In the course of accelerating upwards during the concentric phase of a squat/deadlift, or writhing beneath the bench press, increased capacity (creatine-mediated) for those last vital repetitions translates into enhanced muscle growth.



Creatine: the quintessential to the sublime



Although PCr is commonly associated with the bioenergetics of muscle contraction, increasing evidence confirms that the functional role of PCr extends to several physiologic niches. Of note, PCr enhances ATP repletion in multiple cells with high-energy demands including neurons, skeletal muscle, and spermatozoa. Toward this end, PCr is a highly-conserved, temporally-regulated, energy buffer important for a multiplicity of reasons in several biologic systems. Adding to this growing body of knowledge, we describe recent findings illuminating novel roles for PCr in satellite cell-dependent processes indispensable for muscle growth.



Resistance training is associated with muscle damage and soreness. At the molecular level this process is characterized by a disruption in the cell membrane (sarcolemma) surrounding each muscle fiber, and an infiltration of inflammatory cells. Intuitively, compromising the integrity of the sarcolemma prompts a release of intracellular constituents (including PCr) to the extracellular niche. Of interest, a localized pool of stem cells, called satellite cells, surround each myofiber. In response to signals released from injured muscle, satellite cells undergo an ordered process of events indispensable for muscle repair.



Expansion of satellite cells and their progeny provide a pool of cells expressing muscle-specific proteins. These cells fuse with injured fibers to restore muscle architecture and function. This leads us to a compelling question: could muscle remodeling after damage be an energy-dependent process, and moreover, are satellite cell dynamics (migration, expansion, differentiation, and/or fusion) enhanced in a creatine-dependent manner?

While studying the molecular basis of muscle growth I described a model (O'Connor et al., Journal of Physiology), in which creatine sustains localized ATP-dependent reactions at the interface of fusing muscle cells. Of interest, muscle cell fusion restores muscle architecture during repair after injury; activated satellite cells fuse together to form new myofibers, or fuse with damaged myofibers during regeneration.



To capture the imagination, satellite cells migrate to sites of damage in response to chemotactic signals emanating from muscle fibers. Therein, satellite cells align themselves in preparation for fusion. Satellite cells activate proteins on their surface providing a scaffold for adhesion with injured myofibers. Following adhesion, the membranes of satellite cells and muscle fibers actually merge. Fusion of intracellular constituents' completes the regenerative process. Importantly, a set of cytoskeletal proteins assemble at the interface of opposing cells to regulate this fusion phase. Such extensive cellular reorganization preceding satellite cell fusion is highly energy dependent. Of note, intracellular energy demands are met via an ordered continuum of oxidative phosphorylation, anaerobic glycolysis and finally, PCr hydrolysis. In contrast to other energy sources, PCr hydrolysis provides maximal rates of ATP production with minimal energy cost and no adverse effect on intracellular pH. While glucose oxidation may provide sufficient energy for satellite cell fusion, glycolysis is associated with intracellular acidification through proton accumulation. This may have adverse effects on proteins actively engaging in the fusion process. On this basis, why wouldn't satellite cells rely on PCr for the energy demands of muscle remodeling?



Evidence for creatine-mediated benefits in satellite cell fusion is provided in the accompanying figure. Mindful to add, these are results from in vitro cell culture studies. Therein, the addition of creatine to differentiating satellite cells increased the number of nuclei contained in myotubes (the differentiated progeny of satellite cells; analogous to myofibers in vivo). The myonuclear domain hypothesis of muscle growth, elegantly described by Dr Scott Connelly on the HEAVY MUSCLE RADIO (http://www.rxmuscle.com/hmr-radio-show/1423-jefftheproducer-hmr.html) podcast, establishes that coordinated increases in nuclei and cytoplasmic volume occur during muscle growth. Nuclei are intracellular programming centers. They contain a genetic blueprint/template for the synthesis of new proteins within their immediate vicinity. As each nucleus regulates a finite volume of cytoplasm, there must be coordinated increments in nuclei with increased muscle size. Thus, adding nuclei to growing/regenerating myofibers through satellite cell-dependent processes is indispensable for muscle growth. We anticipate that future studies, using various models of regeneration after muscle damage, will extend these findings on phosphocreatine and satellite cell-dependent muscle growth.







Additional Reading:

O' Connor et al., (2008). Phosphocreatine as an energy source for actin cytoskeletal rearrangements during myoblast fusion. J Physiol., (586), 2841-53.
Saks, V. (2008). The phosphocreatine-creatine kinase system helps to shape muscle cells and keep them healthy and alive. J Physiol., (586), 2817-18.
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DBS

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MessageSujet: Re: La créatine   Jeu 4 Nov - 9:34

Merci yep
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PI3RRUSS3

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MessageSujet: Re: La créatine   Mar 4 Jan - 1:45

pas ton post
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PI3RRUSS3

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MessageSujet: Re: La créatine   Jeu 6 Jan - 0:21

mal*
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heracles 13

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MessageSujet: Re: La créatine   Jeu 6 Jan - 0:38

si vous avez de l'argent a jeter par la fenetre acheter de la créatine c pareil
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thejpman

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MessageSujet: Re: La créatine   Jeu 6 Jan - 1:23

Creatine supplementation improves memory in vegetarians

Creatine monohydrate, a commonly used dietary supplement by athletes to improve athletic performance, has been the subject of several research studies.

In addition to the studies involving creatine’s effects on athletic performance, researchers have also studies its effects on the brain itself–specifically involving effects on memory and cognition.

Though 95% of your body’s available creatine pools are found in skeletal muscle, high levels can also be found in your brain, testes, and heart. As such, since creatine acts as a reserve of high energy phosphate (in the form of phosphocreatine), supplementation with creatine may have effects on cognition as well.

Creatine and Cognition?
Previous research suggests that vegetarians often have lower levels of creatine which makes sense intuitively as well since creatine is predominantly found in meat, fish, and other animal products.

Though previous research studies have looked at the cognitive effects of creatine supplementation, they have found mixed results. One study found that 6 weeks of creatine supplementation had no effects on the cognition of young adults [1]. In this study, the dose of creatine only worked out to about 1.5 – 2 g of creatine per day.

On the other hand, another previous study found that a larger dose (5 g taken 4 times per day) for 2 weeks resulted in improved cognition in an elderly population [2]. Other research suggests that creatine supplementation is more likely to improve cognition in sleep deprived individuals [3].

Creatine and memory?
Most recently, researchers from the University of Swansea published the results of a short-term study on the effects of creatine supplementation on memory, vigilance, and verbal-fluency in omnivores and vegetarians [4].

The study itself included 128 female participants who were divided into two groups based on their dietary habits (vegetarian vs. omnivore). The participants were randomized to 5 day supplementation of creatine (20 g/day) or placebo.

Bottom line:

In short, the study found that supplementation with creatine improved memory (word recall test) in vegetarians, but actually worsened recall in omnivores. The researchers did not observe any effect of creatine supplementation on verbal fluency in either group. Regardless of the dietary habits, both groups demonstrated a decrease in variability of reaction times when supplementing with creatine.

References:

Rawson ES, Lieberman HR, Walsh TM, et al. (2008) Creatine supplementation does not improve cognitive function in young adults. Physiol Behav 95, 130–134
McMorris T, Mielcarz G, Harris RC, et al. (2007) Creatine supplementation and cognitive performance in elderly individuals. Aging Neuropsychol Cogn 14, 517–528.
McMorris T, Harris RC, Swain J, et al. (2006) Effect of creatine supplementation and sleep deprivation, with mild exercise, on cognitive and psychomotor performance, mood state, and plasma concentrations of catecholamines and cortisol. Psychopharmacology 185, 93–103.
Benton D, Donohoe R. The influence of creatine supplementation on the cognitive functioning of vegetarians and omnivores. Br J Nutr. 2010 Dec 1:1-6.
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thejpman

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MessageSujet: Re: La créatine   Jeu 6 Jan - 1:26

Does Creatine Monohydrate Improve Blood Sugar Control?

Listening to the news recently, there’s a tremendous amount of buzz surrounding type 2 diabetes. Currently, statistics from the Center for Disease Control and Prevention(CDC) suggest that one in ten Americans has type 2 diabetes. A new report from the CDC notes that by 2050, a staggering one in three Americans will have type 2 diabetes in current trends continue.

The projected increase in the incidence of type 2 diabetes is largely tied to the rising obesity epidemic. Concern has been raised that the combination of the aging population along with the increased incidence of type 2 diabetes could bankrupt the Canadian healthcare system due to the enormous costs associated with treating this condition.

In the same report from the CDC, they cite statistics that a 58% reduction in the onset of type 2 diabetes can be achieved by a 5-7% weight reduction along with just 150 minutes of exercise per week.

A recent study published in the journal, Medicine and Science in Sports and Exercise (Gualano et al, 2010), investigated whether or not creatine supplementation has a beneficial effect on blood sugar control in patients with type 2 diabetes who engage in an exercise program.

The study included 25 participants who were randomized to take 5 mg/d of creatine or placebo for 12 weeks while they engaged in an exercise training program.

The primary outcome measure of this study was glycosylated hemoglobin (HbA1C). This is a test that doctors routinely order on patients with diabetes to measure the effectiveness of their long-term blood sugar control

The study found that creatine supplementation significantly reduced HbA1C levels:

HBA1c was significantly reduced in the creatine group when compared to the placebo group (CR PRE: 7.4±0.7, POST: 6.4±0.4; PL PRE: 7.5±0.6, POST: 7.6±0.7; p=0.004; difference: -1.1%, 95% confidence interval: -1.9 to -0.4).
The study authors concluded that creatine supplementation along with routine exercise significantly improved glycemic control in patients with type 2 diabetes (compared to exercise + placebo).

Reference:

Gualano B, de Salles Painneli V, Roschel H, Artioli GG, Junior MN, Lúcia de Sá Pinto A, Rossi da Silva ME, Cunha MR, Otaduy MC, da Costa Leite C, Ferreira JC, Pereira RM, Brum PC, Bonfá E, Lancha AH Junior. Creatine in Type 2 Diabetes: A Randomized, Double-Blind, Placebo-Controlled Trial. Med Sci Sports Exerc. 2010 Sep 24.

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thejpman

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MessageSujet: Re: La créatine   Jeu 6 Jan - 1:32

New research study on low dose creatine?

Though creatine is one of the most well-researched ergogenic or performance-enhancing supplements available, a new study explored the effects of altering the dosing range to achieve different results. Specifically, a new study published in the journal, Nutrition,explored the effect of low dose creatine supplementation on body composition and muscle function (Rawson et al, 2010).

Study design:

20 healthy men and women (21 +/- 2 y old) were randomized to receive either creatine (0.03 g . kg(-1) . d(-1) or placebo for 6 weeks in a double blind placebo-controlled study.
Given that an average male weights about 72kg, this dose of creatine would typically approximate to 2.16 grams/day. This dose is much lower than a typical creatine loading or maintenance dose.
What did the subjects do for those six weeks? According to the study authors, they were instructed to maintain similar habitual dietary and physical behaviors during the study.

Results:

No significant increases in body mass, lean body mass, fat mass, total body water, body fat percent, or maximal strength
Plasma creatine increased significantly in the creatine supplementation group only (+182%, p=.03)
The creatine supplementation group was more resistant to fatigue during sets 2 (7%), 3 (9%), 4 (9%), and 5 (11%) (all P < 0.05).
The placebo group did not demonstrate an improvement in fatigue resistance in comparison.
Study author conclusions:

“CONCLUSION: Ingesting a low dose ( approximately 2.3 g/d) of creatine for 6 wk significantly increased plasma creatine concentration and enhanced resistance to fatigue during repeated bouts of high-intensity contractions.”
My thoughts:

I once did a research study on methylphenidate which involved comparing the behaviour response to methylphenidate (Ritalin) among different subtypes of patients with Attention-deficit disorder. The study never did get published and my supervisor at the time joked that we should submit it to “the Journal of Negative Results.”

What did he mean? Well, basically there’s a bias against publishing studies that have negative findings. Why? There’s a potential that the negative result is not valid due to a Type II error. Type II errors occur when you fail to find a difference when there really is one due to poor sensitivity.

In this case, though the authors wrote that their hypothesis was:

“We hypothesized that very low-dose creatine ingestion, when ingested over a sufficient period, would improve muscle function.”
I am somewhat skeptical based on the data tables that they present. Though their data for group by time interaction didn’t reach the level of statistical significance for changes in body composition in either group, the placebo group actually demonstrated improvements in fat free mass, total body weight and reductions in fat mass and body fat % (not statistically significant). In contrast, their creatine group demonstrated nearly the opposite effect. The creatine intervention group demonstrated decreases in body mass, and total body weight, while increasing their body fat percentage and fat free mass (not statistically significant).

If I had to guess, the level of activity and diet was probably not well controlled based on those results. I would venture a guess that this “negative” data lead the study authors to their post-hoc analysis of the effect of low-dose creatine on muscle function.

In fact, the positive findings in this study (increased resistance to fatigue) were found in post-hoc analysis which means that these were not measures that they were specifically looking for prior to the onset of the study. This is sometimes referred to as the post-hoc data dredge and is a method used by researchers so that they don’t have to submit their study results to the Journal of Negative Results.

Bottom line:

This poorly constructed study suggests that low-dose creatine supplementation might be effective for cranking out an extra rep or so if you consume creatine for six weeks. Would I bother with low-dose creatine? No, if I were going to use creatine, I would look at more effective dosing regimes.

Previous research on Creatine:


When taken at dose of 20 g/day (divided in four doses of 5g each for 5 days), creatine has been shown to improve anaerobic performance in swimmers.
Creatine taken at a dose of 9g/day along with 36g/day of protein and 6 g/day of conjugated lineoleic acid has been shown to increase strength and lean tissue mass in response to resistance training.
A comparison of a combination of creatine/protein/carboydrate was more effective in promoting muscle hypertrophy than the protein/carbohydrate supplement alone.
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thejpman

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MessageSujet: Re: La créatine   Jeu 6 Jan - 1:43

Does Creatine Monohydrate Improve Anaerobic Performance?

It’s been a little while since my last post on this blog. I thought that I would blow the dust off this blog and start writing posts again. When it comes to dietary supplements, there’s no question that their use is popular among athletes. Both Olympic and professional athletes seem to share an esurient desire to find a competitive edge in their respective sports. For some, they make the unfortunate and dangerous decisions to cheat by using illegal, performance-enhancing, drugs which can have deadly consequences. yet others, opt for safer alternatives with common choices including energy drinks/bars, protein powders, and creatine monohydrate.

What effect does creatine monohydrate have on competitive swimmers (anaerobic enhancement?)
One mistake that I’ve probably made in my previous posts is writing to a more medically savvy audience, so I will try to make an effort now to write for a typical reader. To answer the question about what effect creatine monohydrate has on anaerobic performance, there’s a recent article published in the journal, Acta Physiologica Hungaria (Juhasz et al, 2009) that address this question.

I would imagine that the difference between placing fourth or first at the Olympic games could translate into hundreds of thousands of dollars in terms of endorsements. Not everyone is born with Michael Phelps’ genetic makeup which is why athletes look to get an edge whether it be the latest swim gear or dietary supplements.

For this particular study, it was relatively small and it involved 16 male swimmers. For five days, the test subjects ingested creatine monohydrate in four separate doses of 5 grams each (total of 20 grams of creatine). From what I understand, each 5 gram dose is about one table spoon of creatine.

What’s interesting is that they tested for three different measures:

Average power output determined by a Bosco test
Maximal 100m fin swim times.
Measured lactate concentration after (Lactate levels rise with anaerobic exercise as a by-product of metabolism)
Results of the study:

Average power of continuous 1 minute rebound jumps improved in Creatine group by 20.2%
Swim times were reduced in creatine group but remained unchanged in control group
Lactate levels were significantly less after 5-minute restitution on the second measurement in both groups.
[ first (pre: 50.69+/-1.41 s; post: 48.86+/-1.34 s) and second (pre: 50.39+/-1.38 s; post: 48.53+/-1.35 s) sessions.]
From the results, the study authors concluded:

The results of this study indicate that five-day Cr supplementation enhances the dynamic strength and may increase anaerobic metabolism in the lower extremity muscles, and improves performance in consecutive maximal swims in highly trained adolescent fin swimmers.
In terms of this particular study, the study itself is relatively small. As well, this study looked specifically at the impact of creatine supplementation on anaerobic power in the lower extremities of trained fin swimmers, which means that the results might not be applicable to other populations/muscle groups.

Note: However, creatine monohydrate is one of the better studied dietary supplements for performance-enhancement in athletes. There’s a number of other placebo-controlled studies supporting the various benefits of creatine.

For those who’ve tried creatine, what have been your experiences with this supplement?

Reference:

Juhász I, Györe I, Csende Z, Rácz L, Tihanyi J. Creatine supplementation improves the anaerobic performance of elite junior fin swimmers. Acta Physiol Hung. 2009 Sep;96(3):325-36.

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MessageSujet: Re: La créatine   Jeu 6 Jan - 1:47

Creatine monohydrate, 15 years later and still going strong…

The topic of my sixth article in this running series on dietary supplements that may help to improve athletic performance is creatine…

Thinking back to the early 1990’s, creatine monohydrate created somewhat of a paradigm shift in the marketing of dietary supplements to the bodybuilding market. From my recollection alone, two primary methods were used to market bodybuilding supplements at that time. The first method involved endorsements which were usually found in bodybuilding magazines from various professional bodybuilders.

Typically, you would see a full page ad in one of these magazines featuring a 250 lb bodybuilder (or larger) with maybe less than 5% body fat with a smile on his face endorsing some new supplement. Though most astute readers would probably question whether or not this spokesperson’s results were from this new featured product or years of steroid abuse, this method of marketing seemed to produce results.

To be certain, the second method of marketing dietary supplements was no more convincing. This method featured the ‘before and after’ photos along with quotes of “I gained X lbs of muscle mass and lost X Lbs of fat while taking this supplement for 8 weeks!” In most cases, the individuals in these before and after photos would be holding up a newspaper or magazine with the date highlighted.

Often, these photos were quite humorous as you could be pretty certain of two things. First, the individual would be ten shades darker from a tanning lotion or bed in the after photo. Secondly, the same results could often be produced in front of your mirror by deliberately protruding your abdomen to recreate the ‘before” photo and subsequently ‘sucking it in’ to create the ‘after’ photo. Either way, these companies usually solicited individuals to send in their before and after photos with lucrative prizes being offered to the winner.

From my understanding, creatine monohydrate first became commercially available for strength enhancement in 1993. At the time, it was brought to market by a company called Experimental and Applied Sciences (EAS) under the brand name Phosphagen®. Though the popularity of the first two marketing methods has not waned, companies now have a third element in their marketing toolbox which includes providing clinical research evidence to support their products.

Years later, creatine monohydrate use remains popular among athletes. A previous article post of mine, reviews a clinical study which suggests that creatine actually does work to increase muscle hypertrophy. To support this, a recent study published in the international journal of sports nutrition and exercise metabolism suggests that creatine supplementation may increase levels of intramuscular IGF-1 (Burke et al, 2008). IGF-1 or Insulin-like growth factor 1, is an anabolic hormone which has a structure similar to insulin.

Does creatine monohydrate increase insulin-like growth factor (IGF-I)?
Study by Burke et al, 2008:

Intervention: “creatine (CR: 0.25 g/kg lean-tissue mass for 7 days; 0.06 g/kg lean-tissue mass for 49 days.”

Results: “Results showed that RET (resistance exercise training) increased intramuscular IGF-I content by 67%, with greater accumulation from CR (+78%) than PL (+54%; p=.06).”

Conclusions:

“These findings indicate that creatine supplementation during resistance-exercise training increases intramuscular IGF-I concentration in healthy men and women, independent of habitual dietary routine.”
Effect of creatine monohydrate on gaining muscle?
Additionally, another recent research study (Kerksick et al, 2007) suggests that subjects who consumed creatine when combined with either protein or colostrum experienced greater gains in fat-free mass (FFM) in comparison to subjects who consumed protein and colostrum or protein alone. Strictly speaking, colostrum is the early milk produced for a few days after delivery. From a dietary supplement perspective, bovine colostrum which is derived from cows is commonly marketed. Colostrum contains protein, carbohydrates, antibodies, and growth factors.

References:

Burke DG, Candow DG, Chilibeck PD, MacNeil LG, Roy BD, Tarnopolsky MA, Ziegenfuss T. Effect of creatine supplementation and resistance-exercise training on muscle insulin-like growth factor in young adults. Int J Sport Nutr Exerc Metab. 2008 Aug;18(4):389-98.
Kerksick CM, Rasmussen C, Lancaster S, Starks M, Smith P, Melton C, Greenwood M, Almada A, Kreider R. Impact of differing protein sources and a creatine containing nutritional formula after 12 weeks of resistance training. Nutrition. 2007 Sep;23(9):647-56.
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