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Creatine, More
than a sports nutrition supplement"
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By Will Brink, author of:
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"Creatine: More than a sports nutrition
supplement"
Although creatine offers an array of
benefits, most people think of it simply as a supplement that bodybuilders
and other athletes use to gain strength and muscle mass. Nothing could be
further from the truth.
A substantial body of research has found that creatine may have a wide
variety of uses. In fact, creatine is being studied as a supplement that may
help with diseases affecting the neuromuscular system, such as muscular
dystrophy (MD). Recent studies suggest creatine may have therapeutic
applications in aging populations for wasting syndromes, muscle atrophy,
fatigue, gyrate atrophy, Parkinson's disease, Huntington's disease and other
brain pathologies. Several studies have shown creatine can reduce
cholesterol by up to 15% and it has been used to correct certain inborn
errors of metabolism, such as in people born without the enzyme(s)
responsible for making creatine. Some studies have found that creatine may
increase growth hormone production.
What is creatine?
Creatine is formed in the human body from the amino acids methionine,
glycine and arginine. The average person's body contains approximately 120
grams of creatine stored as creatine phosphate. Certain foods such as beef,
herring and salmon, are fairly high in creatine. However, a person would
have to eat pounds of these foods daily to equal what can be obtained in one
teaspoon of powdered creatine.
Creatine is directly related to adenosine triphosphate (ATP). ATP is formed
in the powerhouses of the cell, the mitochondria. ATP is often referred to
as the "universal energy molecule" used by every cell in our bodies. An
increase in oxidative stress coupled with a cell's inability to produce
essential energy molecules such as ATP, is a hallmark of the aging cell and
is found in many disease states. Key factors in maintaining health are the
ability to: (a) prevent mitochondrial damage to DNA caused by reactive
oxygen species (ROS) and (b) prevent the decline in ATP synthesis, which
reduces whole body ATP levels. It would appear that maintaining antioxidant
status (in particular intra-cellular glutathione) and ATP levels are
essential in fighting the aging process.
It is interesting to note that many of the most promising anti-aging
nutrients such as CoQ10, NAD, acetyl-l-carnitine and lipoic acid are all
taken to maintain the ability of the mitochondria to produce high energy
compounds such as ATP and reduce oxidative stress. The ability of a cell to
do work is directly related to its ATP status and the health of the
mitochondria. Heart tissue, neurons in the brain and other highly active
tissues are very sensitive to this system. Even small changes in ATP can
have profound effects on the tissues' ability to function properly. Of all
the nutritional supplements available to us currently, creatine appears to
be the most effective for maintaining or raising ATP levels.
How does creatine work?
In a nutshell, creatine works to help generate energy. When ATP loses a
phosphate molecule and becomes adenosine diphosphate (ADP), it must be
converted back to ATP to produce energy. Creatine is stored in the human
body as creatine phosphate (CP) also called phosphocreatine. When ATP is
depleted, it can be recharged by CP. That is, CP donates a phosphate
molecule to the ADP, making it ATP again. An increased pool of CP means
faster and greater recharging of ATP, which means more work can be
performed. This is why creatine has been so successful for athletes. For
short-duration explosive sports, such as sprinting, weight lifting and other
anaerobic endeavors, ATP is the energy system used.
To date, research has shown that ingesting creatine can increase the total
body pool of CP which leads to greater generation of energy for anaerobic
forms of exercise, such as weight training and sprinting. Other effects of
creatine may be increases in protein synthesis and increased cell hydration.
Creatine has had spotty results in affecting performance in endurance sports
such as swimming, rowing and long distance running, with some studies
showing no positive effects on performance in endurance athletes. Whether or
not the failure of creatine to improve performance in endurance athletes was
due to the nature of the sport or the design of the studies is still being
debated.
Creatine can be found in the form of
creatine monohydrate, creatine citrate, creatine phosphate,
creatine-magnesium chelate and even liquid versions. However, the vast
majority of research to date showing creatine to have positive effects on
pathologies, muscle mass and performance used the monohydrate form. Creatine
monohydrate is over 90% absorbable. What follows is a review of some of the
more interesting and promising research studies with creatine.
Creatine and neuromuscular diseases
One of the most promising areas of research with creatine is its effect on
neuromuscular diseases such as MD. One study looked at the safety and
efficacy of creatine monohydrate in various types of muscular dystrophies
using a double blind, crossover trial. Thirty-six patients (12 patients with
facioscapulohumeral dystrophy, 10 patients with Becker dystrophy, eight
patients with Duchenne dystrophy and six patients with sarcoglycan-deficient
limb girdle muscular dystrophy) were randomized to receive creatine or
placebo for eight weeks. The researchers found there was a "mild but
significant improvement" in muscle strength in all groups. The study also
found a general improvement in the patients' daily-life activities as
demonstrated by improved scores in the Medical Research Council scales and
the Neuromuscular Symptom scale. Creatine was well tolerated throughout the
study period, according to the researchers.1
Another group of researchers fed creatine monohydrate to people with
neuromuscular disease at 10 grams per day for five days, then reduced the
dose to 5 grams per day for five days. The first study used 81 people and
was followed by a single-blinded study of 21 people. In both studies, body
weight, handgrip, dorsiflexion and knee extensor strength were measured
before and after treatment. The researchers found "Creatine administration
increased all measured indices in both studies." Short-term creatine
monohydrate increased high-intensity strength significantly in patients with
neuromuscular disease.2 There have also been many clinical observations by
physicians that creatine improves the strength, functionality and
symptomology of people with various diseases of the neuromuscular system.
Creatine and neurological protection/brain injury
If there is one place creatine really shines, it's in protecting the brain
from various forms of neurological injury and stress. A growing number of
studies have found that creatine can protect the brain from neurotoxic
agents, certain forms of injury and other insults. Several in vitro studies
found that neurons exposed to either glutamate or beta-amyloid (both highly
toxic to neurons and involved in various neurological diseases) were
protected when exposed to creatine.3 The researchers hypothesized that "…
cells supplemented with the precursor creatine make more phosphocreatine (PCr)
and create larger energy reserves with consequent neuroprotection against
stressors."
More recent studies, in vitro and in vivo in animals, have found creatine to
be highly neuroprotective against other neurotoxic agents such as
N-methyl-D-aspartate (NMDA) and malonate.4 Another study found that feeding
rats creatine helped protect them against tetrahydropyridine (MPTP), which
produces parkinsonism in animals through impaired energy production. The
results were impressive enough for these researchers to conclude, "These
results further implicate metabolic dysfunction in MPTP neurotoxicity and
suggest a novel therapeutic approach, which may have applicability in
Parkinson's disease."5 Other studies have found creatine protected neurons
from ischemic (low oxygen) damage as is often seen after strokes or
injuries.6
Yet more studies have found creatine may play a therapeutic and or
protective role in Huntington's disease7, 8 as well as ALS (amyotrophic
lateral sclerosis).9 This study found that "… oral administration of
creatine produced a dose-dependent improvement in motor performance and
extended survival in G93A transgenic mice, and it protected mice from loss
of both motor neurons and substantia nigra neurons at 120 days of age.
Creatine administration protected G93A transgenic mice from increases in
biochemical indices of oxidative damage. Therefore, creatine administration
may be a new therapeutic strategy for ALS." Amazingly, this is only the tip
of the iceberg showing creatine may have therapeutic uses for a wide range
of neurological disease as well as injuries to the brain. One researcher who
has looked at the effects of creatine commented, "This food supplement may
provide clues to the mechanisms responsible for neuronal loss after
traumatic brain injury and may find use as a neuroprotective agent against
acute and delayed neurodegenerative processes."
Creatine and heart function
Because it is known that heart cells are dependent on adequate levels of ATP
to function properly, and that cardiac creatine levels are depressed in
chronic heart failure, researchers have looked at supplemental creatine to
improve heart function and overall symptomology in certain forms of heart
disease. It is well known that people suffering from chronic heart failure
have limited endurance, strength and tire easily, which greatly limits their
ability to function in everyday life. Using a double blind,
placebo-controlled design, 17 patients aged 43 to 70 years with an ejection
fraction <40 were supplemented with 20 grams of creatine daily for 10 days.
Before and after creatine supplementation, the researchers looked at:
1) Ejection fraction of the heart (blood present in the ventricle at the end
of diastole and expelled during the contraction of the heart)
2) 1-legged knee extensor (which tests strength)
3) Exercise performance on the cycle ergometer (which tests endurance)
Biopsies were also taken from muscle to determine if there was an increase
in energy-producing compounds (i.e., creatine and creatine phosphate).
Interestingly, but not surprisingly, the ejection fraction at rest and
during the exercise phase did not increase. However, the biopsies revealed a
considerable increase in tissue levels of creatine and creatine phosphate in
the patients getting the supplemental creatine. More importantly, patients
getting the creatine had increases in strength and peak torque (21%, P <
0.05) and endurance (10%, P < 0.05). Both peak torque and 1-legged
performance increased linearly with increased skeletal muscle
phosphocreatine (P < 0.05). After just one week of creatine supplementation,
the researchers concluded: "Supplementation to patients with chronic heart
failure did not increase ejection fraction but increased skeletal muscle
energy-rich phosphagens and performance as regards both strength and
endurance. This new therapeutic approach merits further attention."10
Another study looked at the effects of creatine supplementation on endurance
and muscle metabolism in people with congestive heart failure.11 In
particular the researchers looked at levels of ammonia and lactate, two
important indicators of muscle performance under stress. Lactate and ammonia
levels rise as intensity increases during exercise and higher levels are
associated with fatigue. High-level athletes have lower levels of lactate
and ammonia during a given exercise than non-athletes, as the athletes'
metabolism is better at dealing with these metabolites of exertion, allowing
them to perform better. This study found that patients with congestive heart
failure given 20 grams of creatine per day had greater strength and
endurance (measured as handgrip exercise at 25%, 50% and 75% of maximum
voluntary contraction or until exhaustion) and had lower levels of lactate
and ammonia than the placebo group. This shows that creatine supplementation
in chronic heart failure augments skeletal muscle endurance and attenuates
the abnormal skeletal muscle metabolic response to exercise.
It is important to note that the whole-body lack of essential high energy
compounds (e.g. ATP, creatine, creatine phosphate, etc.) in people with
chronic congestive heart failure is not a matter of simple malnutrition, but
appears to be a metabolic derangement in skeletal muscle and other
tissues.12 Supplementing with high energy precursors such as creatine
monohydrate appears to be a highly effective, low cost approach to helping
these patients live more functional lives, and perhaps extend their life
spans.
Conclusion
Creatine is quickly becoming one of the most well researched and promising
supplements for a wide range of diseases. It may have additional uses for
pathologies where a lack of high energy compounds and general muscle
weakness exist, such as fibromyalgia. People with fibromyalgia have lower
levels of creatine phosphate and ATP levels compared to controls.13 Some
studies also suggest it helps with the strength and endurance of healthy but
aging people as well. Though additional research is needed, there is a
substantial body of research showing creatine is an effective and safe
supplement for a wide range of pathologies and may be the next big find in
anti-aging nutrients. Although the doses used in some studies were quite
high, recent studies suggest lower doses are just as effective for
increasing the overall creatine phosphate pool in the body. Two to three
grams per day appears adequate for healthy people to increase their tissue
levels of creatine phosphate. People with the aforementioned pathologies may
benefit from higher intakes, in the 5-to-10 grams per day range.
About the Author - William D. Brink
Will Brink is a columnist, contributing consultant, and writer for various
health/fitness, medical, and bodybuilding publications. His articles
relating to nutrition, supplements, weight loss, exercise and medicine can
be found in such publications as Lets Live, Muscle Media 2000, MuscleMag
International, The Life Extension Magazine, Muscle n Fitness, Inside Karate,
Exercise For Men Only, Body International, Power, Oxygen, Penthouse, Women’s
World and The Townsend Letter For Doctors.
He is the author of Priming The Anabolic
Environment and Weight Loss Nutrients Revealed. He is the Consulting Sports
Nutrition Editor and a monthly columnist for Physical magazine and an Editor
at Large for Power magazine. Will graduated from Harvard University with a
concentration in the natural sciences, and is a consultant to major
supplement, dairy, and pharmaceutical companies.
He has been co author of several studies relating to sports nutrition and
health found in peer reviewed academic journals, as well as having
commentary published in JAMA. He runs the highly popular web site
BrinkZone.com which is strategically positioned to fulfill the needs and
interests of people with diverse backgrounds and knowledge. The BrinkZone
site has a following with many sports nutrition enthusiasts, athletes,
fitness professionals, scientists, medical doctors, nutritionists, and
interested lay people. William has been invited to lecture on the benefits
of weight training and nutrition at conventions and symposiums around the
U.S. and Canada, and has appeared on numerous radio and television programs.
William has worked with athletes ranging from professional bodybuilders,
golfers, fitness contestants, to police and military personnel.
See Will's ebooks online here:
Muscle
Building Nutrition
A complete guide bodybuilding supplements and eating to gain lean muscle
Diet Supplements
Revealed
A review of diet supplements and guide to eating for maximum fat loss
He can be contacted at: PO Box 812430
Wellesley MA. 02482.
BrinkZone.com
Email: will@brinkzone.com
Natural
Bodybuilding at its Finest - Lift for Life.com
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Article References:
1. Walter MC, et al. Creatine monohydrate
in muscular dystrophies: A double blind, placebo-controlled clinical study.
Neurology 2000 May 9; 54(9): 1848-50.
2. Tarnopolsky M, et al. Creatine monohydrate increases strength in patients
with neuromuscular disease. Neurology 1999 Mar 10; 52(4): 854-7.
3. Protective effect of the energy precursor creatine against toxicity of
glutamate and beta-amyloid in rat hippocampal neurons. J Neurochem
1968-1978; 74(5).
4. Malcon C, et al. Neuroprotective effects of creatine administration
against NMDA and malonate toxicity. Brain Res 2000; 860(1-2): 195-8.
5. Matthews RT, et al. Creatine and cyclocreatine attenuate MPTP
neurotoxicity. Exp Neurol 1999; 157(1): 142-9.
6. Balestrino M, et al. Role of creatine and phosphocreatine in neuronal
protection from anoxic and ischemic damage. Amino Acids Abstract 2002;
23(1-3): 221-229.
7. Matthews RT, et al. Neuroprotective effects of creatine and cyclocreatine
in animal models of Huntington's disease. J Neurosci 1998; 18(1): 156-163.
8. Ferrante RJ, et al. Neuroprotective effects of creatine in a transgenic
mouse model of Huntington's disease. J Neurosci 2000; 20(12): 4389-97.
9. Klivenyi P, et al. Neuroprotective effects of creatine in a transgenic
animal model of amyotrophic lateral sclerosis. Nat Med 1999; 5(3): 347-50.
10. Gordon A, et al. Creatine supplementation in chronic heart failure
increases skeletal muscle creatine phosphate and muscle performance.
Cardiovasc Res 1995 Sep; 30(3): 413-8.
11. Andrews R, et al. The effect of dietary creatine supplementation on
skeletal muscle metabolism in congestive heart failure. Eur Heart J 1998
Apr; 19(4): 617-22.
12. Broqvist M, et al. Nutritional assessment and muscle energy metabolism
in severe chronic congestive heart failure-effects of long-term dietary
supplementation. Eur Heart J 1994 Dec; 15(12): 1641-50.
13. Park JH, et al. Use of P-31 magnetic resonance spectroscopy to detect
metabolic abnormalities in muscles of patients with fibromyalgia. Arthritis
Rheum 1998 Mar; 41(3): 406-13.
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