Creatine Studies

Hanley

Hey all,

I'm trying to pull together some creatine studies that show it's not a dangerous supplement at all.

I KNOW it isn't but my mum is playing the concerned ignorant parent act at the moment so I need something to shut her up with. Apparently the GP said to stay away with anything that has creatine in it (red meat's clearly out so!, no wait, it's ok cos it's "natural").

I tried to explain he was used to dealing with sick people and as a nutritionist he was unreliable but she said "he's looking at it from a medical perspective". I just ignored her because there was no point replying. Eventually she left.

It's not something I expect to be let drop tho so I plan on having the facts to shut her up once and for all with.

It would probably be helpful to point me towards any studies that showed it had the potential to be harmful too, jsut so I've a response ready in case they come up.

Oh and the funniest part is she keeps calling it "Carnatine". That should give you an idea of how much she knows....

Thanks guys (and girls!).

g'em

Ok, here's what I've found from a *very quick* pubmed search. If you have any questions on any of the terminology or you want a better explanation of any of them let me know (that goes for everyone not just Hanley!!). Haven't actually gone through them all myself, I'm head wrecked trying to edit my own paper for submission


1: Mil Med. 2007 Mar;172(3):312-7.

The effect and safety of short-term creatine supplementation on performance of
push-ups.

Armentano MJ, Brenner AK, Hedman TL, Solomon ZT, Chavez J, Kemper GB, Salzberg
D, Battafarano DF, Christie DS.

Physical Therapy Department, Chinle Comprehensive Health Care Facility, Chinle,
AZ 86503, USA.

The effects of short-term oral creatine (Cr) supplementation on exercise
performance and on blood pressure and renal function were assessed. Thirty-five
healthy, active duty, U.S. Army volunteers (20 men and 15 women; age, 22-36
years) at Fort Sam Houston, Texas, supplemented their diet for 7 days with 20
g/day of either Cr or taurine (as placebo). There was no significant difference
in 2-minute push-up counts between the Cr and taurine groups from before to
after supplementation (p = 0.437; power = 0.98). The Cr group demonstrated a
significant increase in serum creatinine levels (p < 0.001), compared with the
taurine group, and this increase could be misinterpreted as impairment of renal
function. No adverse changes in blood pressure, body composition, weight, or
serum Cr phosphokinase levels were observed. We conclude that short-term Cr
supplementation appears to be safe but does not enhance push-up performance.

Publication Types:
Research Support, U.S. Gov't, Non-P.H.S.

PMID: 17436778 [PubMed - in process]

2: J Ren Nutr. 2006 Oct;16(4):341-5.

Acute renal failure in a young weight lifter taking multiple food supplements,
including creatine monohydrate.

Thorsteinsdottir B, Grande JP, Garovic VD.

Department of Internal Medicine, Mayo Clinic College of Medicine, Rochester, MN
55902, USA.

We report a case of a healthy 24-year-old man who presented with acute renal
failure and proteinuria while taking creatine and multiple other supplements for
bodybuilding purposes. A renal biopsy showed acute interstitial nephritis. The
patient recovered completely after he stopped taking the supplements. Creatine
is a performance-enhancing substance that has gained widespread popularity among
professional as well as amateur athletes. It is legal and considered relatively
safe. Recently there have been case reports of renal dysfunction, including
acute interstitial nephritis, associated with its use. Further studies are
needed to evaluate the safety of creatine supplementation. It may be prudent to
include a warning of this possible side effect in the product insert.

Publication Types:
Case Reports

PMID: 17046619 [PubMed - indexed for MEDLINE]

3: Regul Toxicol Pharmacol. 2006 Aug;45(3):242-51. Epub 2006 Jun 30.

Risk assessment for creatine monohydrate.

Shao A, Hathcock JN.

Council for Responsible Nutrition, 1828 L St., NW, Suite 900,Washington, DC
20036-5114, USA. ashao@crnusa.org

Creatine monohydrate (creatine) has become an increasingly popular ingredient in
dietary supplements, especially sports nutrition products. A large body of human
and animal research suggests that creatine does have a consistent ergogenic
effect, particularly with exercises or activities requiring high intensity short
bursts of energy. Human data are primarily derived from three types of studies:
acute studies, involving high doses (20 g/d) with short duration (< or = 1
week), chronic studies involving lower doses (3-5 g/d) and longer duration (1
year), or a combination of both. Systematic evaluation of the research designs
and data do not provide a basis for risk assessment and the usual safe Upper
Level of Intake (UL) derived from it unless the newer methods described as the
Observed Safe Level (OSL) or Highest Observed Intake (HOI) are utilized. The OSL
risk assessment method indicates that the evidence of safety is strong at
intakes up to 5 g/d for chronic supplementation, and this level is identified as
the OSL. Although much higher levels have been tested under acute conditions
without adverse effects and may be safe, the data for intakes above 5 g/d are
not sufficient for a confident conclusion of long-term safety.

Publication Types:
Review

PMID: 16814437 [PubMed - indexed for MEDLINE]

4: Neurology. 2006 Mar 14;66(5):664-71. Epub 2006 Feb 15.

Comment in:
Neurology. 2006 Mar 14;66(5):626-7.

A randomized, double-blind, futility clinical trial of creatine and minocycline
in early Parkinson disease.

NINDS NET-PD Investigators.

BACKGROUND: Creatine and minocycline were prioritized for testing in Phase II
clinical trials based on a systematic evaluation of potentially disease
modifying compounds for Parkinson disease (PD). OBJECTIVE: To test whether
creatine and minocycline alter the course of early PD relative to a
predetermined futility threshold for progression of PD in a randomized,
double-blind, Phase II futility clinical trial. Agents that do not perform
better than the futility threshold are rejected as futile and are not considered
for further study. METHODS: Participants had a diagnosis of PD within 5 years,
but did not require medications for the management of symptoms. The primary
outcome was the change in the total Unified Parkinson's Disease Rating Scale
(UPDRS) score from baseline to either the time when there was sufficient
disability to warrant symptomatic therapy for PD or 12 months, whichever came
first. Subjects were randomized 1:1:1 to receive creatine 10 g/day, minocycline
200 mg/day, or matching placebo. The futility threshold was set as a 30%
reduction in UPDRS progression based on the placebo/tocopherol arm of the
Deprenyl And Tocopherol Antioxidative Therapy Of Parkinsonism (DATATOP) trial. p
values < or = 0.1 indicate futility. RESULTS: Two hundred subjects were
randomized to the three groups. Neither creatine (p = 0.96) nor minocycline (p =
0.66) could be rejected as futile based on the DATATOP futility threshold. The
rate of progression for the calibration placebo group fell outside the 95% CI
for the DATATOP historical control. In a sensitivity analysis, based on the
threshold derived from the calibration placebo group, again neither drug could
be rejected as futile. Tolerability was 91% in the creatine group and 77% in the
minocycline group. Common adverse events included upper respiratory symptoms
(26%), joint pain (19%), and nausea (17%). CONCLUSIONS: Both creatine and
minocycline should be considered for definitive Phase III trials to determine if
they alter the long term progression of Parkinson disease (PD). Additional
factors must be weighed before selecting agents for Phase III trials, including
safety, tolerability, activity, cost, and availability of these two agents in
comparison with other agents currently in development for PD.

Publication Types:
Clinical Trial, Phase II
Multicenter Study
Randomized Controlled Trial
Research Support, N.I.H., Extramural

PMID: 16481597 [PubMed - indexed for MEDLINE]

5: Mayo Clin Proc. 2005 Oct;80(10):1307-15.

Erratum in:
Mayo Clin Proc. 2006 Jan;81(1):133.

Cardiovascular toxicities of performance-enhancing substances in sports.

Dhar R, Stout CW, Link MS, Homoud MK, Weinstock J, Estes NA 3rd.

Department of Clinical Care Research, Institute for Clinical Research and Health
Policy Studies, Tufts University-New England Medical Center, Boston, MA 02111,
USA. RDhar@tufts-nemc.org

Athletes commonly use drugs and dietary supplements to improve athletic
performance or to assist with weight loss. Some of these substances are
obtainable by prescription or by illegal means; others are marketed as
supplements, vitamins, or minerals. Nutritional supplements are protected from
Food and Drug Administration regulation by the 1994 US Dietary Supplement Health
and Education Act, and manufacturers are not required to demonstrate proof of
efficacy or safety. Furthermore, the Food and Drug Administration lacks a
regulatory body to evaluate such products for purity. Existing scientific data,
which consist of case reports and clinical observations, describe serious
cardiovascular adverse effects from use of performance-enhancing substances,
including sudden death. Although mounting evidence led to the recent ban of
ephedra (ma huang), other performance-enhancing substances continue to be used
frequently at all levels, from elementary school children to professional
athletes. Thus, although the potential for cardiovascular injury is great, few
appropriately designed studies have been conducted to assess the benefits and
risks of using performance-enhancing substances. We performed an exhaustive OVID
MEDLINE search to Identify all existing scientific data, review articles, case
reports, and clinical observations that address this subject. In this review, we
examine the current evidence regarding cardiovascular risk for persons using
anabolic-androgenic steroids including 2 synthetic substances,
tetrahydrogestrinone and androstenedione (andro), stimulants such as ephedra,
and nonsteroidal agents such as recombinant human erythropoietin, human growth
hormone, creatine, and beta-hydroxy-beta-methylbutyrate.

Publication Types:
Review

PMID: 16212144 [PubMed - indexed for MEDLINE]

6: Curr Opin Pediatr. 2005 Oct;17(5):653-7.

Dietary supplement use in adolescents.

Dorsch KD, Bell A.

University of Regina, Regina, Saskatchewan, Canada. Kim.Dorsch@uregina.ca

PURPOSE OF REVIEW: As prevalence rates of dietary supplement use are observed to
be increasing in adolescents and the population in general, questions need to be
asked about the efficacy, motivations, and consequences of such usage. Focusing
mainly on individuals between the ages of 12 to 19 (adolescents) this review
will highlight current prevalence rates, types of supplements being consumed,
reasons for consumption, and concerns regarding physiological, psychological,
knowledge transfer, and regulatory aspects of supplement use. RECENT FINDINGS:
Studies have indicated the prevalence of dietary supplement usage by adolescents
range from approximately 10% to as high as 74%. Some of the highest rates of
usage appear in chronically ill adolescents. Multivitamin and mineral
preparations are the most common supplements being consumed; however, many
studies indicate that adolescents are using other substances like creatine,
herbals, or protein supplements. Some of the most appealing supplements among
this age group are those that enhance athletic performance or physical
appearance. Recent literature suggests three key moderating factors for
supplement use in adolescents: health status, gender, and level of physical
activity involvement. SUMMARY: As the dietary supplement industry is now a
multi-billion dollar industry, there is growing pressure, and a subsequent need
for research to establish the efficacy and safety of these products particularly
for adolescent users. The psychological and educational components of such use
cannot be ignored as they play an equally important role in the health and
safety of adolescents.

Publication Types:
Review

PMID: 16160543 [PubMed - indexed for MEDLINE]

7: CNS Drugs. 2004;18(14):967-80.

The role of creatine in the management of amyotrophic lateral sclerosis and
other neurodegenerative disorders.

Ellis AC, Rosenfeld J.

Carolinas Neuromuscular/ALS Center, Charlotte, North Carolina 28203, USA.
amy.ellis@carolinahealthcare.org

Creatine is consumed in the diet and endogenously synthesised in the body. Over
the past decade, the ergogenic benefits of synthetic creatine monohydrate have
made it a popular dietary supplement, particularly among athletes. The anabolic
properties of creatine also offer hope for the treatment of diseases
characterised by weakness and muscle atrophy. Moreover, because of its cellular
mechanisms of action, creatine offers potential benefits for diseases involving
mitochondrial dysfunction. Recent data also support the hypothesis that creatine
may have a neuroprotective effect. Amyotrophic lateral sclerosis (ALS) is
characterised by progressive degeneration of motor neurons, resulting in
weakening and atrophy of skeletal muscles. In patients with this condition,
creatine offers potential benefits in terms of facilitating residual muscle
contractility as well as improving neuronal function. It may also help stabilise
mitochondrial dysfunction, which plays a key role in the pathogenesis of ALS.
Indeed, the likely multifactorial aetiology of ALS means the combined
pharmacodynamic properties of creatine offer promise for the treatment of this
condition. Evidence from available animal models of ALS supports the utility of
treatment with creatine in this setting. Limited data available in other
neuromuscular and neurodegenerative diseases further support the potential
benefit of creatine monohydrate in ALS. However, few randomised, controlled
trials have been conducted. To date, two clinical trials of creatine monohydrate
in ALS have been completed without demonstration of significant improvements in
overall survival or a composite measure of muscle strength. These trials have
also posed unanswered questions about the optimal dosage of creatine and its
beneficial effects on muscle fatigue, a measure distinct from muscle strength. A
large, multicentre, clinical trial is currently underway to further investigate
the efficacy of creatine monohydrate in ALS and address these unresolved issues.
Evidence to date shows that creatine supplementation has a good safety profile
and is well tolerated by ALS patients. The purpose of this article is to provide
a short, balanced review of the literature concerning creatine monohydrate in
the treatment of ALS and related neurodegenerative diseases. The
pharmacokinetics and rationale for the use of creatine are described along with
available evidence from animal models and clinical trials for ALS and related
neurodegenerative or neuromuscular diseases.

Publication Types:
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.
Review

PMID: 15584767 [PubMed - indexed for MEDLINE]

8: Toxicol Lett. 2004 Sep 25;152(3):275.

Comment on:
Toxicol Lett. 2004 Apr 15;150(1):123-30.

Creatine: a safety concern.

Archer MC.

Publication Types:
Comment
Letter

PMID: 15331137 [PubMed - indexed for MEDLINE]

9: Toxicol Lett. 2004 Sep 25;152(3):273-4.

Comment on:
Toxicol Lett. 2004 Apr 15;150(1):123-30.

Writing about creatine: is it worth the risk?

Wyss M.

DSM Nutritional Products, Biotech R & D, Building 203/17B, P.O. Box 3255,
CH-4002 Basel, Switzerland. markus.wyss@dsm.com

Publication Types:
Comment

PMID: 15331136 [PubMed - indexed for MEDLINE]

10: J Herb Pharmacother. 2004;4(1):1-7.

Effects of creatine supplementation on renal function.

Yoshizumi WM, Tsourounis C.

Cedars-Sinai Medical Center, Los Angeles, CA., USA.

Creatine is a popular supplement used by athletes in an effort to increase
muscle performance. The purpose of this review was to assess the literature
evaluating the effects of creatine supplementation on renal function. A PubMed
search was conducted to identify relevant articles using the keywords, creatine,
supplementation, supplements, renal dysfunction, ergogenic aid and renal
function. Twelve pertinent articles and case reports were identified. According
to the existing literature, creatine supplementation appears safe when used by
healthy adults at the recommended loading (20 gm/day for five days) and
maintenance doses (</=3 gm/day). In people with a history of renal disease or
those taking nephrotoxic medications, creatine may be associated with an
increased risk of renal dysfunction. One case report of acute renal failure was
reported in a 20-year-old man taking 20 gm/day of creatine for a period of four
weeks. There are few trials investigating the long-term use of creatine
supplementation in doses exceeding 10 gm/day. Furthermore, the safety of
creatine in children and adolescents has not been established. Since creatine
supplementation may increase creatinine levels, it may act as a false indicator
of renal dysfunction. Future studies should include renal function markers other
than serum creatinine and creatinine clearance.

Publication Types:
Review

PMID: 15273072 [PubMed - indexed for MEDLINE]

11: J Orthop Sports Phys Ther. 2003 Oct;33(10):615-21.

Creatine supplementation and athletic performance.

Racette SB.

Washington University School of Medicine, Program in Physical Therapy,
Department of Medicine, St. Louis, MO 63108-2212, USA.
racettes@msnotes.wustl.edu

Nutritional supplements and other ergogenic aids have gained widespread use
among professional, amateur, recreational, and student athletes for their
potential to enhance athletic performance and provide a competitive edge.
Creatine monohydrate is one of the more commonly used and potentially beneficial
supplements that currently is viewed to be safe. Supplementation with oral
creatine augments skeletal muscle creatine concentrations in most individuals,
which has been shown to promote gains in lean body mass when used in conjunction
with resistance training, to enhance power and strength, and to improve
performance in intense exercise, especially during repeated bouts. Young
athletes, however, must be cautious about taking creatine because its effects on
growth and development are unknown and long-term safety has not been
established. Variability in research study designs and small sample sizes have
left many questions unanswered regarding the safety and efficacy of chronic
supplementation. This is an active area of clinical investigation and the
results of ongoing and future research should guide the appropriate use of
creatine to enhance athletic performance among athletes of all ages.

Publication Types:
Review

PMID: 14620790 [PubMed - indexed for MEDLINE]

12: Neurology. 2003 Jul 8;61(1):141-2.

Creatine therapy for Huntington's disease: clinical and MRS findings in a 1-year
pilot study.

Tabrizi SJ, Blamire AM, Manners DN, Rajagopalan B, Styles P, Schapira AH, Warner
TT.

Department of Neurodegenerative Disease, Institute of Neurology, Queen Square,
London, UK.

Publication Types:
Clinical Trial
Controlled Clinical Trial
Research Support, Non-U.S. Gov't

PMID: 12847181 [PubMed - indexed for MEDLINE]

13: Curr Sports Med Rep. 2002 Apr;1(2):103-6.

Effects of creatine use on the athlete's kidney.

Farquhar WB, Zambraski EJ.

HRCA Research and Training Institute, Harvard Division on Aging, 1200 Centre
Street, Boston, MA 02131, USA. farquhar@mail.hrca.harvard.edu

With regard to athletes attempting to improve their performance, at the present
time creatine monohydrate is clearly the most widely used dietary supplement or
ergogenic aid. Loading doses as high as 20 g/d are typical among athletes. The
majority (> 90%) of the creatine ingested is removed from the plasma by the
kidney and excreted in the urine. Despite relatively few isolated reports of
renal dysfunction in persons taking creatine, the studies completed to date
suggest that in normal healthy individuals the kidneys are able to excrete
creatine, and its end product creatinine, in a manner that does not adversely
alter renal function. This situation would be predicted to be different in
persons with impaired glomerular filtration or inherent renal disease. The
question of whether long-term creatine supplementation (ie, months to years) has
any deleterious affects on renal structure or function can not be answered at
this time. The limited number of studies that have addressed the issue of the
chronic use of creatine have not seen remarkable changes in renal function.
However, physicians should be aware that the safety of long-term creatine
supplementation, in regard to the effects on the kidneys, cannot be guaranteed.
More information is needed on possible changes in blood pressure,
protein/albumin excretion, and glomerular filtration in athletes who are
habitual users of this compound.

Publication Types:
Case Reports
Review

PMID: 12831718 [PubMed - indexed for MEDLINE]

14: Curr Sports Med Rep. 2002 Dec;1(6):369-73.

Supplement use in the adolescent athlete.

DesJardins M.

The University of Utah, The Orthopedic Specialty Hospital, 5848 South 300 East,
Salt Lake City, UT 84107, USA. mtdmd@hotmail.com

Use of dietary supplements has become common practice among adolescent athletes
in the United States. Concern has arisen regarding safety in adolescents in
light of the fact that supplements are not required to meet usual US Food and
Drug Administration requirements for standard pharmaceuticals. Furthermore,
advertised ergogenic gains are based on little or no scientific evidence.
Creatine, anabolic steroids, androstenedione, dehydroepiandrosterone, caffeine,
ephedrine-type alkaloids, calcium beta-hydroxy-beta-methybutyrate, and human
growth hormone are reviewed. Although some studies have indicated performance
benefit in particular athletic situations, there are few available data in
adolescents. Furthermore, the few safety studies of these supplements do not
include adolescents. Adolescents may be at particular risk when using anabolic
steroids and caffeine-ephedra combinations. Research has demonstrated effective
education programs can reduce adolescents' intentions to use dietary
supplements.

Publication Types:
Review

PMID: 12831686 [PubMed - indexed for MEDLINE]

15: Mol Cell Biochem. 2003 Feb;244(1-2):95-104.

Long-term creatine supplementation does not significantly affect clinical
markers of health in athletes.

Kreider RB, Melton C, Rasmussen CJ, Greenwood M, Lancaster S, Cantler EC, Milnor
P, Almada AL.

Exercise and Sport Nutrition Laboratory, Department of Human Movement Sciences
and Education, The University of Memphis, Memphis, TN, USA.
Richard_Kreider@baylor.edu

Creatine has been reported to be an effective ergogenic aid for athletes.
However, concerns have been raised regarding the long-term safety of creatine
supplementation. This study examined the effects of long-term creatine
supplementation on a 69-item panel of serum, whole blood, and urinary markers of
clinical health status in athletes. Over a 21-month period, 98 Division IA
college football players were administered in an open label manner creatine or
non-creatine containing supplements following training sessions. Subjects who
ingested creatine were administered 15.75 g/day of creatine monohydrate for 5
days and an average of 5 g/day thereafter in 5-10 g/day doses. Fasting blood and
24-h urine samples were collected at 0, 1, 1.5, 4, 6, 10, 12, 17, and 21 months
of training. A comprehensive quantitative clinical chemistry panel was
determined on serum and whole blood samples (metabolic markers, muscle and liver
enzymes, electrolytes, lipid profiles, hematological markers, and lymphocytes).
In addition, urine samples were quantitatively and qualitative analyzed to
assess clinical status and renal function. At the end of the study, subjects
were categorized into groups that did not take creatine (n = 44) and subjects
who took creatine for 0-6 months (mean 4.4 +/- 1.8 months, n = 12), 7-12 months
(mean 9.3 +/- 2.0 months, n = 25), and 12-21 months (mean 19.3 +/- 2.4 months, n
= 17). Baseline and the subjects' final blood and urine samples were analyzed by
MANOVA and 2 x 2 repeated measures ANOVA univariate tests. MANOVA revealed no
significant differences (p = 0.51) among groups in the 54-item panel of
quantitative blood and urine markers assessed. Univariate analysis revealed no
clinically significant interactions among groups in markers of clinical status.
In addition, no apparent differences were observed among groups in the 15-item
panel of qualitative urine markers. Results indicate that long-term creatine
supplementation (up to 21-months) does not appear to adversely effect markers of
health status in athletes undergoing intense training in comparison to athletes
who do not take creatine.

Publication Types:
Research Support, Non-U.S. Gov't

PMID: 12701816 [PubMed - indexed for MEDLINE]

16: Sports Med. 2003;33(3):177-85.

Use of nonsteroidal anti-inflammatory drugs following exercise-induced muscle
injury.

Baldwin Lanier A.

Department of Health, Physical Education and Sport Science, Kennesaw State
University, Kennesaw, Georgia 30144-5591, USA. alanier@kennesaw.edu

The objective of this article is to examine the use of NSAIDs for attenuating
exercise-induced muscle injuries (EIMI), with an emphasis on their safety and
usefulness for improving muscle function and reducing soreness. NSAIDs are some
of the most widely consumed medications in the world, and NSAID use as therapy
for EIMI has increased dramatically over the last 20 years. However, there is a
lack of agreement concerning NSAID effectiveness for this purpose. The lack of
consensus about the efficacy of NSAID use in relation to EIMI has spawned a
recent interest in sports medicine research regarding NSAIDs. The application of
a variety of methods used to induce, assess and quantify muscle injury has
contributed to the inconsistency among the findings regarding the efficacy of
NSAIDs for EIMI. Therefore, future studies should focus on the evaluation of
muscle injury and function, with the use of better functional measurement tools
and more uniformity in the assessment tools used. However, from review of the
current literature, it is concluded that NSAID use for brief periods of time is
beneficial for short-term recovery of muscle function and is an important
laboratory tool for the study of EIMI.

Publication Types:
Review

PMID: 12656639 [PubMed - indexed for MEDLINE]

17: Neurology. 2003 Feb 11;60(3):500-2.

Creatine monohydrate in DM2/PROMM: a double-blind placebo-controlled clinical
study. Proximal myotonic myopathy.

Schneider-Gold C, Beck M, Wessig C, George A, Kele H, Reiners K, Toyka KV.

Department of Neurology, University of Wurzburg, Germany.
chris.schneider@mail.uni-wuerzburg.de

The efficacy and safety of creatine monohydrate (Cr) in patients with myotonic
dystrophy type 2/proximal myotonic myopathy were studied in a small
placebo-controlled double-blind trial. Twenty patients received either Cr or
placebo for 3 months. After 3 months, there were no significant differences of
muscle strength as assessed by hand-held dynamometry, testing of maximum grip
strength, Medical Research Council scoring, and the Neuromuscular Symptom Score
between the two groups. Some measures indicated trends toward mild improvement
with Cr. Myalgia improved in two patients.

Publication Types:
Clinical Trial
Randomized Controlled Trial
Research Support, Non-U.S. Gov't

PMID: 12578937 [PubMed - indexed for MEDLINE]

18: Nephrol Dial Transplant. 2003 Feb;18(2):258-64.

Creatine supplementation does not affect kidney function in an animal model with
pre-existing renal failure.

Taes YE, Delanghe JR, Wuyts B, van de Voorde J, Lameire NH.

Laboratory of Clinical Chemistry, Department of Internal Medicine, University
Hospital Ghent, De Pintelaan 185, B-9000 Ghent, Belgium.

BACKGROUND: Creatine is widely used as an ergogenic substance among athletes.
Safety of prolonged creatine intake has been questioned, based upon case reports
and animal data. We investigated the effect of prolonged creatine ingestion on
renal function in animals with normal kidney function or pre-existing kidney
failure, respectively. METHODS: Male Wistar rats were randomly allocated to four
experimental groups: (i) sham-operated, control diet; (ii) sham-operated,
creatine-supplemented diet (2% w/w (0.9+/-0.2 g creatine/kg body weight/day));
(iii) two-thirds nephrectomized, control diet; and (iv) two-thirds
nephrectomized, creatine supplemented diet. Glomerular filtration rate was
determined using inulin and creatinine clearance, together with albumin
excretion, urea clearance, muscle and serum creatine and serum cystatin C
concentrations. RESULTS: In contrast to previous reports, no detrimental effects
of creatine supplementation on the renal function indices were observed in
two-thirds nephrectomized or sham-operated animals. No differences were observed
in inulin (0.28+/-0.08 vs 0.25+/-0.08 ml/min/100 g; P=NS) or creatinine
clearance rates. Serum cystatin C concentration, urinary protein excretion, and
albumin and urea clearance were comparable between creatine-supplemented and
control-diet fed animals in both sham-operated and two-thirds nephrectomized
animals. Serum creatine and intramuscular total creatine concentrations were
higher in creatine-supplemented groups (P<0.05). CONCLUSIONS:Creatine
supplementation at a dosage of 2% w/w for 4 weeks does not impair kidney
function in animals with pre-existing renal failure or in control animals.

Publication Types:
Research Support, Non-U.S. Gov't

PMID: 12543878 [PubMed - indexed for MEDLINE]

19: J Neurol. 2002 Dec;249(12):1717-22.

Creatine monohydrate in myotonic dystrophy: a double-blind, placebo-controlled
clinical study.

Walter MC, Reilich P, Lochmuller H, Kohnen R, Schlotter B, Hautmann H, Dunkl E,
Pongratz D, Muller-Felber W.

Friedrich-Baur-Institute, Department of Neurology,
Ludwig-Maximilians-University, Ziemssenstr. 1a, 80336 Munich, Germany.
Maggie.Walter@lrz.uni-muenchen.de

We assessed safety and efficacy of creatine monohydrate (Cr) in myotonic
dystrophy (DM1) in a double-blind, cross-over trial. Thirty-four patients with
defined DM1 were randomized to receive Cr and placebo for eight weeks (10.6 g
day 1-10, 5.3 g day 11-56) in one of 2 treatment sequences. There was no
significant improvement using manual and quantitative muscle strength,
daily-life activities, and patients' own global assessment comparing verum with
placebo administration. Cr supplementation was well tolerated without clinically
relevant side effects, but did not result in significant improvement of muscle
strength or daily-life activities.

Publication Types:
Clinical Trial
Comparative Study
Randomized Controlled Trial
Research Support, Non-U.S. Gov't

PMID: 12529796 [PubMed - indexed for MEDLINE]

20: J Fam Pract. 2002 Nov;51(11):945-51.

Does oral creatine supplementation improve strength? A meta-analysis.

Dempsey RL, Mazzone MF, Meurer LN.

Dept of Family Community Medicine, Medical College of Wisconsin, 8701 Watertown
Plank Road, Milwaukee, WI 53226, USA. rdempsey@mcw.edu

OBJECTIVES: Oral creatine is the most widely used nutritional supplement among
athletes. Our purpose was to investigate whether creatine supplementation
increases maximal strength and power in healthy adults. STUDY DESIGN:
Meta-analysis of existing literature. DATA SOURCES: We searched MEDLINE
(1966-2000) and the Cochrane Controlled Trials Register (through June 2001) to
locate relevant articles. We reviewed conference proceedings and bibliographies
of identified studies. An expert in the field was contacted for sources of
unpublished data. Randomized or matched placebo controlled trials comparing
creatine supplementation with placebo in healthy adults were considered.
OUTCOMES MEASURED: Presupplementation and postsupplementation change in maximal
weight lifted, cycle ergometry sprint peak power, and isokinetic dynamometer
peak torque were measured. RESULTS: Sixteen studies were identified for
inclusion. The summary difference in maximum weight lifted was 6.85 kg (95%
confidence interval [CI], 5.24-8.47) greater after creatine than placebo for
bench press and 9.76 kg (95% CI, 3.37-16.15) greater for squats; there was no
difference for arm curls. In 7 of 10 studies evaluating maximal weight lifted,
subjects were young men (younger than 36 years) engaged in resistance training.
There was no difference in cycle ergometer or isokinetic dynamometer
performance. CONCLUSIONS: Oral creatine supplementation combined with resistance
training increases maximal weight lifted in young men. There is no evidence for
improved performance in older individuals or women or for other types of
strength and power exercises. Also, the safety of creatine remains unproven.
Therefore, until these issues are addressed, its use cannot be universally
recommended.

Publication Types:
Comparative Study
Meta-Analysis
Research Support, U.S. Gov't, P.H.S.

PMID: 12485548 [PubMed - indexed for MEDLINE]

21: Curr Opin Pediatr. 2002 Dec;14(6):719-22.

Prevention of sports injuries in children.

Flynn JM, Lou JE, Ganley TJ.

The Children's Hospital of Philadelphia, University of Pennsylvania School of
Medicine, and the Sports Medicine and Performance Center at The Children's
Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA.
flynnj@email.chop.edu

As children around the world become involved in increasingly competitive and
more organized sports activities, the frequency and severity of both acute and
overuse injuries continues to rise. Over the past year, several important
studies have contributed to our knowledge in the prevention of sports injuries
in children. Safety guidelines and protective equipment are crucial to
minimizing pediatric recreational injuries. Protective headgear, mouth guards,
and wrist and shin guards have all been shown to be effective in preventing
injuries. Nutrition and nutritional supplements (eg, creatine) for the pediatric
athlete have also received greater attention recently. Combined with appropriate
physical activity programs, nutrition is essential in battling the increasing
epidemic of childhood obesity. Increased attention has also been directed toward
specific injuries and injury rates in the female athlete. Specific training for
the female pediatric athlete may have a preventive effect in halting the rising
injury rates.

Publication Types:
Review

PMID: 12436044 [PubMed - indexed for MEDLINE]

22: Adv Nurse Pract. 2001 May;9(5):55-8.

Creatine supplementation. Recipe for victory or recipe for risk?

White CL.

North Woods Community Health Center, Minong, Wis., USA.

Publication Types:
Review

PMID: 12400261 [PubMed - indexed for MEDLINE]

23: WMJ. 2002;101(2):25-30.

Creatine supplementation in Wisconsin high school athletes.

McGuine TA, Sullivan JC, Bernhardt DA.

University of Wisconsin Hospital Sports Medicine Center, USA.

BACKGROUND: Creatine is a nutritional supplement used to enhance athletic
performance in collegiate and professional athletes. There is increasing
evidence that high school athletes are using creatine as well. The objective of
this study was to describe patterns of creatine supplementation as well as the
behaviors and beliefs associated with creatine use in high school athletes.
METHODS: 4011 high school student-athletes from 37 public high schools in
Wisconsin took part in a cross-sectional, multi-site, anonymous, descriptive
survey. Measurements included self-reported patterns of creatine use. RESULTS:
16.7% of the athletes (25.3% males, 3.9% females) reported using creatine.
Creatine use was lowest in the 9th grade (8.4%) and highest in the 12th grade
(24.6%). The percentage of participants in each sport who used creatine varied
considerably from 1.3% (female cross country) to 30.1% (football). Increased
strength was the most likely perceived benefit of creatine supplementation,
while dehydration was cited most often as a perceived risk of creatine use.
Users were encouraged to take creatine most often by their friends while their
parents discouraged its use. CONCLUSION: Despite the lack of research regarding
the efficacy or safety of creatine supplementation in high school athletes,
creatine was used by 25% of males and 4% of female high school athletes in
Wisconsin. High school athletes who use creatine may not be aware of the risks
and benefits associated with creatine supplementation. Primary care providers
and sports medicine professionals need to educate athletes, coaches and parents
about the creatine use as a performance enhancing supplement.

Publication Types:
Research Support, Non-U.S. Gov't

PMID: 12085493 [PubMed - indexed for MEDLINE]

24: Neuroscience. 2002;112(2):243-60.

Health implications of creatine: can oral creatine supplementation protect
against neurological and atherosclerotic disease?

Wyss M, Schulze A.

Roche Vitamins AG, Biotechnology Department (VFB), Building 203/113A, CH-4070
Basel, Switzerland. markus.wyss@roche.com

Major achievements made over the last several years have highlighted the
important roles of creatine and the creatine kinase reaction in health and
disease. Inborn errors of metabolism have been identified in the three main
steps involved in creatine metabolism: arginine:glycine amidinotransferase
(AGAT), S-adenosyl-L-methionine:N-guanidinoacetate methyltransferase (GAMT), and
the creatine transporter. All these diseases are characterized by a lack of
creatine and phosphorylcreatine in the brain, and by (severe) mental
retardation. Similarly, knockout mice lacking the brain cytosolic and
mitochondrial isoenzymes of creatine kinase displayed a slightly increased
creatine concentration, but no phosphorylcreatine in the brain. These mice
revealed decreased weight gain and reduced life expectancy, disturbed fat
metabolism, behavioral abnormalities and impaired learning capacity.Oral
creatine supplementation improved the clinical symptoms in both AGAT and GAMT
deficiency, but not in creatine transporter deficiency. In addition, creatine
supplementation displayed neuroprotective effects in several animal models of
neurological disease, such as Huntington's disease, Parkinson's disease, or
amyotrophic lateral sclerosis. All these findings pinpoint to a close
correlation between the functional capacity of the creatine
kinase/phosphorylcreatine/creatine system and proper brain function. They also
offer a starting-point for novel means of delaying neurodegenerative disease,
and/or for strengthening memory function and intellectual capabilities.Finally,
creatine biosynthesis has been postulated as a major effector of homocysteine
concentration in the plasma, which has been identified as an independent graded
risk factor for atherosclerotic disease. By decreasing homocysteine production,
oral creatine supplementation may, thus, also lower the risk for developing,
e.g., coronary heart disease or cerebrovascular disease.Although compelling,
these results require further confirmation in clinical studies in humans,
together with a thorough evaluation of the safety of oral creatine
supplementation.

Publication Types:
Review

PMID: 12044443 [PubMed - indexed for MEDLINE]

25: Pediatrics. 2001 Aug;108(2):421-5.

Creatine use among young athletes.

Metzl JD, Small E, Levine SR, Gershel JC.

Sports Medicine Service, Hospital for Special Surgery, Department of Pediatrics,
Cornell Medical College, New York, New York 10021, USA. MetzlJ@HSS.EDU

OBJECTIVE: Creatine is a nutritional supplement that is purported to be a safe
ergogenic aid in adults. Although as many as 28% of collegiate athletes admit
taking creatine, there is little information about creatine use or potential
health risk in children and adolescents. Although the use of creatine is not
recommended in people less than 18 years of age, numerous anecdotal reports
indicate widespread use in young athletes. The purpose of this study was to
determine the frequency, risk factors, and demographics of creatine use among
middle and high school student athletes. METHODS: Before their annual sports
preparticipation physical examinations, middle and high school athletes aged 10
to 18 in Westchester County, a suburb north of New York City, were surveyed in a
confidential manner. Information was collected regarding school grade, gender,
specific sport participation, and creatine use. RESULTS: Overall, 62 of 1103
participants (5.6%) admitted taking creatine. Creatine use was reported in every
grade, from 6 to 12. Forty-four percent of grade 12 athletes surveyed reported
using creatine. Creatine use was significantly more common (P <.001) among boys
(53/604, 8.8%) than girls (9/492, 1.8%). Although creatine was taken by
participants in every sport, use was significantly more common among football
players, wrestlers, hockey players, gymnasts, and lacrosse players (P <.001 for
all). The most common reasons cited for taking creatine were enhanced
performance (74.2% of users) and improved appearance (61.3%), and the most
common reason cited for not taking creatine was safety (45.7% of nonusers).
CONCLUSIONS: Despite current recommendations against use in adolescents less
than 18 years old, creatine is being used by middle and high school athletes at
all grade levels. The prevalence in grades 11 and 12 approaches levels reported
among collegiate athletes. Until the safety of creatine can be established in
adolescents, the use of this product should be discouraged.

PMID: 11483809 [PubMed - indexed for MEDLINE]

26: Ann Neurol. 2001 May;49(5):561-74.

Comment in:
Ann Neurol. 2002 Jul;52(1):126; author reply 126-7.

Potential for creatine and other therapies targeting cellular energy dysfunction
in neurological disorders.

Tarnopolsky MA, Beal MF.

Department of Neurology, McMaster University, Hamilton, Ontario, Canada.
tarnopol@fhs.mcmaster.ca

Substantial evidence indicates that bioenergetic dysfunction plays either a
primary or secondary role in the pathophysiology of cell death in
neurodegenerative and neuromuscular disorders, and even in normal aging. Agents
that ameliorate bioenergetic defects may therefore be useful in therapy.
Creatine, which increases muscle and brain phosphocreatine concentrations, and
may inhibit the activation of the mitochondrial permeability transition,
protects against neuronal degeneration in transgenic murine models of
amyotrophic lateral sclerosis and Huntington's disease and in chemically
mediated neurotoxicity. Initial studies of creatine use in humans appear
promising; however, further long-term, well-designed trials are needed. Coenzyme
Q10, Gingko biloba, nicotinamide, riboflavin, carnitine, lipoic acid, and
dichloroacetate are other agents which may have beneficial effects on energy
metabolism, but the preclinical and clinical evidence for efficacy in
neurological diseases remains limited. These compounds are widely used as
dietary supplements; however, they must be subjected to rigorous evaluation
through randomized, double-blinded trials to establish efficacy,
cost-effectiveness and safety in neurological disorders.

Publication Types:
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Research Support, U.S. Gov't, P.H.S.
Review

PMID: 11357946 [PubMed - indexed for MEDLINE]

27: J Sports Med Phys Fitness. 2001 Mar;41(1):1-10.

Creatine as nutritional supplementation and medicinal product.

Benzi G, Ceci A.

Department of Physiological-Pharmacological Sciences, Faculty of Science,
University of Pavia, Italy.

Because of assumed ergogenic effects, the creatine administration has become
popular practice among subjects participating in different sports. Appropriate
creatine monohydrate dosage may be considered a medicinal product since, in
accordance with the Council Directive 65/65/EEC, any substance which may be
administered with a view to restoring, correcting or modifying physiological
functions in humans beings is considered a medicinal product. Thus, quality,
efficacy and safety must characterise the substance. In addition, the European
Court of Justice has held that a product which is recommended or described as
having preventive or curative properties is a medicinal product even if it is
generally considered as a foodstuff and even if it has no known therapeutic
effect in the present state of scientific knowledge. In biochemical terms,
creatine administration increases creatine and phosphocreatine muscle
concentration, allowing for an accelerated rate of ATP synthesis. In
thermodynamics terms, creatine stimulates the creatine-creatine
kinase-phosphocreatine circuit, which is related to the mitochondrial function
as a highly organised system for the control of the subcellular adenylate pool.
In pharmacokinetics terms, creatine entry into skeletal muscle is initially
dependent on the extracellular concentration, but the creatine transport is
subsequently downregulated. In pharmacodynamics terms, the creatine enhances the
possibility to maintain power output during brief periods of high-intensity
exercises. In spite of uncontrolled daily dosage and long-term administration,
no researches on creatine monohydrate safety in humans were set up by
standardised protocols of clinical pharmacology and toxicology, as currently
occurs in phases I and II for products for human use. More or less documented
side effects induced by creatine monohydrate are weight gain; influence on
insulin production; feedback inhibition of endogenous creatine synthesis;
long-term damages on renal function. A major point that related to the quality
of creatine monohydrate products is the amount of creatine ingested in relation
to the amount of contaminants present. During the industrial production of
creatine monohydrate from sarcosine and cyanamide, variable amounts of
contaminants (dicyandiamide, dihydrotriazines, creatinine, ions) are generated
and, thus, their tolerable concentrations (ppm) must be defined and made
consumers known. Furthermore, because sarcosine could originate from bovine
tissues, the risk of contamination with prion of bovine spongiform
encephalopathy (BSE or mad-cow disease) can t be excluded. Thus, French
authorities forbade the sale of products containing creatine. Creatine, as other
nutritional factors, can be used either at supplementary or therapeutic levels
as a function of the dose. Supplementary doses of nutritional factors usually
are of the order of the daily turnover, while therapeutic ones are three or more
times higher. In a subject of 70 kg with a total creatine pool of 120 g, the
daily turnover is approximately of 2 g. Thus, in healthy subjects nourished with
fat-rich, carbohydrate, protein-poor diet and participating in a daily
recreational sport, the oral creatine monohydrate supplementation should be of
the order of the daily turnover, i.e., less than 2.5-3 g per day, bringing the
gastrointestinal absorption to account. In healthy athletes submitted daily to
high-intensity strength or sprint training, the maximal oral creatine
monohydrate supplementation should be of the order of two times the daily
turnover, i.e., less than 5-6 g per day for less than two weeks, and the
creatine monohydrate supplementation should be taken under appropriate medical
supervision. The oral administration of more that 6 g per day of creatine
monohydrate should be considered as a therapeutic intervention and should be
prescribed by physicians only in the cases of suspected or proven deficiency, or
in conditions of severe stress and/or injury. The incorporation of creatine into
the medicinal product class is supported also by the use in pathological
conditions, e.g., some mitochondrial cytopathies, the guanidinoacetate
methyltransferase deficiency, etc.

Publication Types:
Review

PMID: 11317142 [PubMed - indexed for MEDLINE]

28: J Nutr. 2001 Mar;131(3s):1114S-7S.

Dietary supplements: how they are used and regulated.

Hathcock J.

Council for Responsible Nutrition, Washington, DC 20036-1609, USA.

Overall use of nutrient and botanical dietary supplements (DS) has increased for
years across all major categories. Many DS are simply taken as part of a healthy
lifestyle, but some are used to reduce risk of or modulate risk factors for
specific chronic diseases, such as heart disease (vitamin E, folic acid,
garlic), cancer (selenium, vitamin E, garlic) and certain birth defects (folic
acid). Other DS are used for short-term benefits such as sleep management
(valerian, melatonin) and enhanced physical performance (pyruvate, creatine). DS
are regulated under food law, but with certain provisions that apply only to DS.
Thus, DS are eligible for Food and Drug Administration (FDA)-authorized health
claims under the Nutrition and Labeling Education Act (NLEA). Health claims have
already been authorized for folic acid and calcium, but not for several others.
In 1994, when the Dietary Supplement Health and Education Act (DSHEA) was
passed, it expanded and clarified the definition of DS, specified additional
requirements for safety and provided for four types of claims of nutritional
support. These include prevention of classic nutritional deficiencies, structure
or function (S/F) effects, mechanisms for S/F effects and general well-being.
Although S/F effects result from both foods and drugs, representation that a
product will treat, cure, mitigate or diagnose a disease is reserved for drugs.
Therefore, the wording of S/F claims for DS has become a difficult issue in the
proposed DS labeling regulations.

Publication Types:
Review

LegacyUser

Holy ****, G'em certainly is on top of her game. My mum says the same thing, spoke to GP's and whatnot and they all say "No Xplode is dangerout, will give you a heart attack."

I just ignore her. haha

mloc

basically what g'em said. I'd try searching for more on pubmed but to be honest, exams coming up and I've pretty much had enough of pubmed for college work.

GPs, damn, if only they knew when to shut the fck up. I'm 6 weeks away from having a Pharmacology degree, and I can say with some confidence, creatine is not going to cause you any more harm than any other vitamin, mineral or nutritional supplement.

Dragan

mloc wrote:

GPs, damn, if only they knew when to shut the fck up. I'm 6 weeks away from having a Pharmacology degree, and I can say with some confidence, creatine is not going to cause you any more harm than any other vitamin, mineral or nutritional supplement.

Yeah, but your not charging parents 50 quid a visit to put the fear in them , so you opinion would be considered moot by those same GP's. :rolleyes:

Foolish doctors.

mloc

Dragan wrote:

Yeah, but your not charging parents 50 quid a visit to put the fear in them

I should really start charging. Having said that, I probably wouldn't be much use if anyone was actually sick bar maybe pointing them towards some drugs.

brianthebard

In my experience that's all doctors do anyways.

InFront

Whoops, better get that Rang and Dale book then, what do doctors know about pharmacology or physiology anyway, here's a thought maybe they should teach pharmacology in medical schools...</sarcasm>

The OP said "apparently" his GP said stay away from it, and we don't know why he said so. Perhaps he means that it isn't actually going to increase the guy's muscle strength and perhaps this is what he needs. In which case telling someone not to bother with creatine is completely sensible.

brianthebard

A lot of doctors know feck all about fitness or nutrition. At least my GP at home had the good grace to say so. Plenty will try and bullsh!t their way through it. Hanley knows that he's making gains and that creatine is involved so that's obviously not the issue.

Hanley

InFront wrote:

Whoops, better get that Rang and Dale book then, what do doctors know about pharmacology or physiology anyway, here's a thought maybe they should teach pharmacology in medical schools...</sarcasm>

The OP said "apparently" his GP said stay away from it, and we don't know why he said so. Perhaps he means that it isn't actually going to increase the guy's muscle strength and perhaps this is what he needs. In which case telling someone not to bother with creatine is completely sensible.

Yeah.... and telling someone to jump off a bridge makes perfect sense too.**

Basically he said it was "dangerous". To be honest I see where he's coming from, he's been out GP for 15+ years, and is almost a family friend at this stage and since the hippocratic oath is all about "first, do no harm". I can see why he'd say stay away from it since there's only a few medium and no real long term studies.

Once that did interest me was this;

15: Mol Cell Biochem. 2003 Feb;244(1-2):95-104.

Long-term creatine supplementation does not significantly affect clinical
markers of health in athletes.

Kreider RB, Melton C, Rasmussen CJ, Greenwood M, Lancaster S, Cantler EC, Milnor
P, Almada AL.

Exercise and Sport Nutrition Laboratory, Department of Human Movement Sciences
and Education, The University of Memphis, Memphis, TN, USA.
Richard_Kreider@baylor.edu

Creatine has been reported to be an effective ergogenic aid for athletes.
However, concerns have been raised regarding the long-term safety of creatine
supplementation. This study examined the effects of long-term creatine
supplementation on a 69-item panel of serum, whole blood, and urinary markers of
clinical health status in athletes. Over a 21-month period, 98 Division IA
college football players were administered in an open label manner creatine or
non-creatine containing supplements following training sessions. Subjects who
ingested creatine were administered 15.75 g/day of creatine monohydrate for 5
days and an average of 5 g/day thereafter in 5-10 g/day doses. Fasting blood and
24-h urine samples were collected at 0, 1, 1.5, 4, 6, 10, 12, 17, and 21 months
of training. A comprehensive quantitative clinical chemistry panel was
determined on serum and whole blood samples (metabolic markers, muscle and liver
enzymes, electrolytes, lipid profiles, hematological markers, and lymphocytes).
In addition, urine samples were quantitatively and qualitative analyzed to
assess clinical status and renal function. At the end of the study, subjects
were categorized into groups that did not take creatine (n = 44) and subjects
who took creatine for 0-6 months (mean 4.4 +/- 1.8 months, n = 12), 7-12 months
(mean 9.3 +/- 2.0 months, n = 25), and 12-21 months (mean 19.3 +/- 2.4 months, n
= 17). Baseline and the subjects' final blood and urine samples were analyzed by
MANOVA and 2 x 2 repeated measures ANOVA univariate tests. MANOVA revealed no
significant differences (p = 0.51) among groups in the 54-item panel of
quantitative blood and urine markers assessed. Univariate analysis revealed no
clinically significant interactions among groups in markers of clinical status.
In addition, no apparent differences were observed among groups in the 15-item
panel of qualitative urine markers. Results indicate that long-term creatine
supplementation (up to 21-months) does not appear to adversely effect markers of
health status in athletes undergoing intense training in comparison to athletes
who do not take creatine.

Personally, I'm ALOT stronger when I'm on creatine. Attribute it to transient factors like weight gain and a bit of a bloat if you want, but the bottom line is my strength's measured on the platform on a given day and if I can put up a PR and creatine has ANY part to play in that whatsoever, then it's making me stronger.



**Provided the bridge is only 5-10 foot high and over a large lake, and the person in question is on fire.

King.Penguin

I just ignored her because there was no point replying. Eventually she left.

lol. I think in the GP's defense, they have a mountain of stuff to deal with and their priorities are for things that they treat the average patient with on a day to day basis. They can't read every journal article or review on every different aspect of medicine. However, creatine has always been a thing they've hidden their heads in the sand about, I don't know why.

I think for serious atheltes you can't go and talk to the average gp about sporting fitness.

in terms of bringing your ma around to the dark side I think you're going to be facing an uphil struggle but you need to remind her that there aren't many substances they sell as food supplements over the counter that kill people. if they did, they're be sued.

mloc

King.Penguin wrote:

in terms of bringing your ma around to the dark side I think you're going to be facing an uphil struggle but you need to remind her that there aren't many substances they sell as food supplements over the counter that kill people. if they did, they're be sued.

This is true. However compare taking the average dose of creatine with, for example, a bucket of southern fried chicken wings. Most likely, the wings contain traces of antibiotics from poorly raised chicken, and are cooked in a trans-fat laden oil which ain't the best for the cardiovascular system. Maybe throw in some fries and a large coke (packed full of sugary goodness) too.

And then ask yourself, which would your mom rather see you eating? Uninformed, she'd prefer you munching on the wings than drinking that funny chemical creatine stuff.

Ignorance is bliss, I guess.

Reyman

Reading through all of those articles G'em. I don't get that good a feeling about Creatine. Very few of the scientists seem to be positive about it's long term effects on health. Now maybe they're just being very cautious

So just one question - do you use it ?

g'em

Reyman wrote:

Reading through all of those articles G'em. I don't get that good a feeling about Creatine. Very few of the scientists seem to be positive about it's long term effects on health. Now maybe they're just being very cautious

So just one question - do you use it ?

Good point. Unfortunately, to date, there just hasn't been any long term studies of chronic creatine use. It's therefore pertinent for scientists/ sports physiologists to err on the side of caution as opposed to saying "Ah sure, we don't actually know what it'll do over a ten year period, but I'm sure you'll be fine!!".

I've actually done more rigorous searches through the literature about this myself because I do take creatine - quite happily I might add - and as with ALL new supplementation I always do a background check on it to decide whether it's worth trying out. Having said that I use it at low doses and irregularly, the primary exception being an 8 week diet during which I took it every training day to keep my energy up.

Like I said, that was a very slapdash and quick journal search, I'll need to go back and look in more detail, but there have been quite a few studies done in both swimmers and cyclists looking at prolonged creatine use (by prolonged they usually mean 10-12 months!!). At best creatine use does have a small significant effect on performance, at worst it has no effect at all but does not reduce performance.

Give me a while and I'll try and unearth some more studies...

g'em

Clin Sci (Lond). 2003 Feb;104(2):153-62.

Effects of creatine loading and prolonged creatine supplementation on body
composition, fuel selection, sprint and endurance performance in humans.

van Loon LJ, Oosterlaar AM, Hartgens F, Hesselink MK, Snow RJ, Wagenmakers AJ.

Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Department of
Human Biology, Maastricht University, Maastricht, The Netherlands.
L.vanLoon@HB.Unimaas.nl

Most research on creatine has focused on short-term creatine loading and its
effect on high-intensity performance capacity. Some studies have investigated
the effect of prolonged creatine use during strength training. However, studies
on the effects of prolonged creatine supplementation are lacking. In the present
study, we have assessed the effects of both creatine loading and prolonged
supplementation on muscle creatine content, body composition, muscle and
whole-body oxidative capacity, substrate utilization during submaximal exercise,
and on repeated supramaximal sprint, as well as endurance-type time-trial
performance on a cycle ergometer. Twenty subjects ingested creatine or a placebo
during a 5-day loading period (20 g.day(-1)) after which supplementation was
continued for up to 6 weeks (2 g.day(-1)). Creatine loading increased muscle
free creatine, creatine phosphate (CrP) and total creatine content ( P <0.05).
The subsequent use of a 2 g.day(-1) maintenance dose, as suggested by an
American College of Sports Medicine Roundtable, resulted in a decline in both
the elevated CrP and total creatine content and maintenance of the free creatine
concentration. Both short- and long-term creatine supplementation improved
performance during repeated supramaximal sprints on a cycle ergometer. However,
whole-body and muscle oxidative capacity, substrate utilization and time-trial
performance were not affected. The increase in body mass following creatine
loading was maintained after 6 weeks of continued supplementation and accounted
for by a corresponding increase in fat-free mass. This study provides definite
evidence that prolonged creatine supplementation in humans does not increase
muscle or whole-body oxidative capacity and, as such, does not influence
substrate utilization or performance during endurance cycling exercise. In
addition, our findings suggest that prolonged creatine ingestion induces an
increase in fat-free mass.

g'em

Med Sci Sports Exerc. 2002 Feb;34(2):332-43.

Effects of creatine supplementation on muscle power, endurance, and sprint
performance.

Izquierdo M, Ibanez J, Gonzalez-Badillo JJ, Gorostiaga EM.

Centro de Investigacion y Medicina del Deporte, Gobierno de Navarra, Navarra,
Spain. mizquierdo@jet.es

PURPOSE: To determine the effects of creatine (Cr) supplementation (20 g x d(-1)
during 5 d) on maximal strength, muscle power production during repetitive
high-power-output exercise bouts (MRPB), repeated running sprints, and endurance
in handball players. METHODS: Nineteen trained male handball players were
randomly assigned in a double-blind fashion to either creatine (N = 9) or
placebo (N = 10) group. Before and after supplementation, subjects performed
one-repetition maximum half-squat (1RM(HS) and bench press (1RM(BP)), 2 sets of
MRPB consisting of one set of 10 continuous repetitions (R10) followed by 1 set
until exhaustion (R(max)), with exactly 2-min rest periods between each set,
during bench-press and half-squat protocols with a resistance equal to 60 and
70% of the subjects' 1RM, respectively. In addition, a countermovement jumping
test (CMJ) interspersed before and after the MRPB half-squat exercise bouts and
a repeated sprint running test and a maximal multistage discontinuous
incremental running test (MDRT) were performed. RESULTS: Cr supplementation
significantly increased body mass (from 79.4 +/- 8 to 80 +/- 8 kg; P < 0.05),
number of repetitions performed to fatigue, and total average power output
values in the R(max) set of MRPB during bench press (21% and 17%, respectively)
and half-squat (33% and 20%, respectively), the 1RM(HS) (11%), as well as the
CMJ values after the MRPB half-squat (5%), and the average running times during
the first 5 m of the six repeated 15-m sprints (3%). No changes were observed in
the strength, running velocity, or body mass measures in the placebo group
during the experimental period. CONCLUSION: Short-term Cr supplementation leads
to significant improvements in lower-body maximal strength, maximal repetitive
upper- and lower-body high-power exercise bouts, and total repetitions performed
to fatigue in the R(max) set of MRPB, as well as enhanced repeated sprint
performance and attenuated decline in jumping ability after MRPB in highly
trained handball players. Cr supplementation did not result in any improvement
in upper-body maximal strength and in endurance running performance.

g'em

Eur J Appl Physiol. 2004 Mar;91(2-3):230-7. Epub 2003 Oct 22.

Short-term creatine supplementation does not improve muscle activation or sprint
performance in humans.

Kinugasa R, Akima H, Ota A, Ohta A, Sugiura K, Kuno SY.

Graduate School of Health and Sport Science, Nippon Sport Science University,
7-1-1 Fukasawa, Setagaya, 158-8508, Tokyo, Japan. kinugasa@nittai.ac.jp

The purpose of this study was to examine the influence of short-term creatine
(Cr) supplementation on exercise-induced transverse relaxation time (T2) and
sprint performance during maximum intermittent cycling exercise using the muscle
functional magnetic resonance imaging (mfMRI) technique. Twelve men were divided
into a Cr supplementation group [the Cr group, taking 4 x (5 g Cr monohydrate +
2.5 g maltodextrin)/day], or a placebo supplementation group (the P group,
taking 4 x 7.5 g maltodextrin/day). The allocation to the groups was based on
cycling tests and the subject's physical characteristics, and thus was not
randomized. A double-blind research design was employed for a 5-day
supplementation period. mfMR images of the right thigh were collected at rest
and immediately after two, five, and ten 6-s sprint bouts of maximum
intermittent cycling exercise with a 30-s recovery interval between sets. Before
and after supplementation, blood was taken to calculate lactate accumulation,
and the muscle volume of the thigh was determined by MRI. Following
supplementation, there was significant body mass gain in the Cr group ( P<0.05),
whereas the P group did not change. The exercise-induced T2, blood lactate
levels and sprint performance were not affected by Cr supplementation in any
sprint bouts. These results suggest that short-term Cr supplementation does not
influence short duration repetitive sprint performance and muscle activation
and/or metabolic state during sprint cycling evaluated by mfMRI of the skeletal
muscle in humans.

g'em

J Sports Med Phys Fitness. 1999 Sep;39(3):189-96.

Oral creatine supplementation improves multiple sprint performance in elite
ice-hockey players.

Jones AM, Atter T, Georg KP.

Department of Exercise and Sport Science, Crewe and Alsager Faculty, Manchester
Metropolitan University, UK.

BACKGROUND: The purpose of this study was to assess the effect of oral creatine
monohydrate supplementation on multiple sprint cycle and skating performance in
ice-hockey players. METHODS: Participants: sixteen elite ice-hockey players were
selected as subjects. Experimental design: subjects were randomly assigned to
either a creatine (Cr) (n = 8) or a placebo (P) group (n = 8) in a double blind
design. After familiarization and baseline tests, subjects loaded with 5 g of
creatine monohydrate or placebo (glucose) four times per day for 5 days, after
which a maintenance dose of 5 g per day for 10 weeks was administered. At
baseline, and after 10 days and 10 weeks of supplementation, subjects performed
i) a cycle test involving 5 all-out sprints of 15 sec duration separated by 15
sec recovery with the resistance set at 0.075 body mass (kg), and ii) 6 timed
80-m skating sprints with the sprints initiated every 30 sec and a split time
taken at 47 m. RESULTS: A two-way ANOVA demonstrated no significant change in
any of the variables in the P group over the period of study. However, in the Cr
group, average mean power output over the 5 sprints was significantly higher at
10 days (1074 +/- 241 W) and 10 weeks (1025 +/- 216 W) than at baseline (890 +/-
172 W), (p < 0.01). Average peak power output over the 5 sprints improved
significantly from baseline (1294 +/- 311 W) to 10 days (1572 +/- 463 W), (p <
0.01). Average on-ice sprint performance to 47 m was significantly faster at 10
days (6.88 +/- 0.21 sec) and 10 weeks (6.96 +/- 0.19 sec) than at baseline (7.17
+/- 0.27 sec), (p < 0.005). CONCLUSIONS: This study demonstrates that creatine
supplementation has an ergogenic effect in elite ice-hockey players.

g'em

J Sports Med Phys Fitness. 2006 Mar;46(1):90-8.

The effect of creatine monohydrate supplementation on sprint skating in
ice-hockey players.

Cornish SM, Chilibeck PD, Burke DG.

College of Kinesiology, University of Saskatchewan, Saskatoon SK, Canada.

AIM: Creatine monohydrate supplementation is beneficial for enhancing
high-intensity exercise performance, especially activities that involve repeated
sprints. Creatine monohydrate supplementation is common in ice-hockey players.
The purpose of this study was to determine the effect of creatine monohydrate
supplementation on sprint skating performance in Junior B and collegiate
ice-hockey players. METHODS: Seventeen ice-hockey players were randomly assigned
to receive creatine (0.3 g/kg body mass/day for 5 days) or placebo. Before and
after supplementation players performed repeated sprints to exhaustion on a
skating treadmill (repeated 10-s sprints; 30-s rest between sprints) while blood
lactate was simultaneously collected. The time to exhaustion on the treadmill
test was calculated as total amount of time, including partial intervals, before
the player reached exhaustion. Players were also tested for peak torque and
average power during knee extension/flexion (3 sets of 10 reps; 60-s rest
between sets) on an isokinetic dynamometer at 60 degrees/s. RESULTS: The change
in time to exhaustion from before to after supplementation averaged 20.6+/-7 s
in the creatine group and 21.9+/-13 s in the placebo group, with no differences
between groups. Likewise, there were no differences between groups for changes
in isokinetic peak torque and average power. There were no differences between
groups over time for blood lactate changes during the repeated sprints on the
treadmill. CONCLUSIONS: We conclude that creatine was not effective for
improving performance in these ice-hockey players.




Alongside the above reference you have a prime example of how similar studies can show two completely different results... :rolleyes:

g'em

J Sports Med Phys Fitness. 2003 Dec;43(4):481-7.

Effects of creatine loading on muscular strength and endurance of female
softball players.

Ayoama R, Hiruma E, Sasaki H.

Human Performance Laboratory, Department of Sports Sciences and Management,
School of Human Science, Osaka International University, Osaka, Japan.

AIM: The purpose of this study was to determine the effects of Cr
supplementation on muscle strength and endurance of the trained females, the
effect of anaerobic exercises performed before the supplementation and
disappearance of the effects on the performance. METHODS: Twenty-six collegiate
female softball players were divided into the Cr1, 2, Control (Cont.)1 or 2
group, randomly. They performed maximal 2-isometric and 30-isokinetic knee
extensions at the angular velocities of 180 degrees and 60 degrees /s.
Thereafter, the subjects of the Cr2 and Cont.2 groups performed resistance
exercises with 10 RM and cycling with 0.01 kg x kg-1 body weight, alternately
during the 1(st) week. During the 2(nd) week, the subjects of the Cr1 and 2
groups ingested 20 g Cr a day for 1 week. Thereafter, the subjects in the Cr2
group continued 3 g Cr ingestion a day for 2 weeks while the Cr1 group ingested
the same amount of placebo during the 3(rd) and 4(th) weeks. The subjects of the
Cont.1, 2 groups ingested the same amount and taste of placebo during the 1(st)
to 4(th) weeks. This study was undergone in double blind fashion. The similar
measurements, to which the subjects performed the 1(st) day, were carried out on
the final day of the 2(nd), 3(rd) and 4(th) weeks. RESULTS: Though maximal
isometric strength did not differ in intra- and intergroups, the isokinetic peak
torque in the Cr1 group was significantly decreased in the 4(th) measurement
(p<0.01). The mean torque of the 1(st) to 10th knee contractions at 60 inverted
exclamation mark /s was significantly decreased from the 2(nd) measurement in
the Cont.1, 2 groups, compared with that in the 1(st) measurement (p<0.01). In
the Cr groups, the significant decrease was detected from the 3(rd) in the Cr1
and in the 4(th) measurement in the Cr2 group. The mean torque of the latter 20
contractions at 180 inverted exclamation mark /s was significantly increased in
the Cr2 group (p<0.001). In the 1(st) measurement, the mean torque in the Cr1
group was significantly higher than that in the Cr2 group (p<0.05). However, the
differences between Cr1 and 2 groups were not detected from the 2(nd)
measurement. CONCLUSION: Twenty g Cr supplementation a day for a week to the
trained females improves not the maximal static strength and dynamic peak torque
but the mean strength and endurance of repeated contractions. However, the
effects on females are not so great as that ever found in males. The effects are
enhanced by anaerobic exercises performed before the supplementation and would
disappear in a week if the supplementation were stopped.






Okay, I could keep going with these indefinitely. The simple fact is there is very little out there on the safety of creatine as a supplement, but there's gazillions of articles discussing its effectiveness.

Even at that, there's no conclusive studies on creatine effectiveness at all. Most studies seem to be on small groups, short term, with athletes that are already at a certain level of ability. There's no obvious agreement between aerobic vs anaerobic activity either.

Honestly? I think you could manipulate the references to reflect *whatever* viewpoint you have on creatine! :rolleyes:

Dragan

g'em wrote:

Honestly? I think you could manipulate the references to reflect *whatever* viewpoint you have on creatine! :rolleyes:

As far as i am aware this can be done with just about anything, ever.

g'em

Dragan wrote:

As far as i am aware this can be done with just about anything, ever.

lol, to a certain extent yeah!! Certainly when you're looking at it from a biological context and trying to explain the intricacies of physiological systems that we don't yet *completely* understand the results of studies can be swayed to suit certain needs. When you add in a supplement it's sometimes difficult to monitor the effects it will have simply because you're looking at processes that are occuring on a cellular level that are very, very hard to quanitfy - are the results actually being induced by that supplement or are they a by-product of another unconsidered reaction?

Oh and as far as the "pump" that comes from commercial creatine supplements is concerned, that's not the creatine at work, it's generally down the presence of arginine and glutamine in the supplement and their effect on nitric oxide release. Nitric oxide (NO - and hence the name NO-Xplode) causes vasodilation (opening) of the blood vessels. This allows more blood to reach the target muscles, thereby increasing nutrient flow to the site allowing for increased muscle growth.