Creatine Information Creatine is a naturally occurring metabolite found in
muscle tissue. It plays an important role in energy metabolism, and ATP
reformulating. Muscle soreness, lactate build up, and fatigue are a direct
result of depleted ATP store. Creatine replenishes ATP stores, thus prolonging
time to fatigue. Creatine also increases available instant energy, increases
muscular strength, improves endurance, and reduces levels of metabolic
byproducts such as ammonia (Ammonia is produced at high levels during intense
exercise, ammonia is partially responsible for muscular fatigue). From our
experience, Creatine supplementation results in significant muscle accumulation
and increased muscular endurance in all of our clients. Weight gains from 4-14
pounds are common place with Creatine supplementation. Creatine loading via
supplemental feeding can also offer the potential for the following. Improved
Athletic Performance: Maximizing the level of stored Creatine (20% or more) by
supplemental ingestion of Creatine Monohydrate, has been shown to extend peak
athletic performance for longer periods during short duration, high intensity
exercise. Stockpiling Creatine shortens the time necessary for the body to
generate replacement Creatine, thus significantly reducing muscle recovery time
between short duration, high intensity activities. Increase Lean Muscle Mass:
Inactive or dystrophic muscle (such as occurs as a result of injury) has by
nature reduced levels of Creatine. Supplementation with Creatine Monohydrate
permits dystrophic muscle to work harder during therapy and rebuild itself to
its normal state. Correct Creatine Deficiencies: Disease or age-related Creatine
deficiencies in the brain and skeletal muscle can be improved by the oral
administration of Creatine Monohydrate, helping to restore a more active, normal
lifestyle. How to Use Creatine Loading / Maintenance Phase: Take one to two
scoops immediatley after workout, that's it. Creatine is best utilized when
taken with a high glycemic substance such as (grape juice, Ultra fuel, ect.)
Creatine Monohydrate - How Does It Really Works? Glenn Peden offered the
following from Tom McCullough via the FEMUSCLE list on Tuesday, 13June1995. It
was forwarded to me in response to my call for information on Creatine. Glenn:
My Dad said he read mail today. Hope he can answer all of your questions. I have
been powerlifting for 13 years. I lift in the 242 lb. weight class. I am also
ranked #9 in the USA. If you have not tried the creatine monohydrate, get some.
Just a quick explanation of its actions. I'm sure you know in order for a muscle
to contract energy has to be released through the breakdown of ATP. In strength
training you are in an anaerobic system. The only way ATP is made is through
anaerobic glycolisis. ATP is also reformed in the anaerobic system when chemical
reactions take place in the muscle forcing the biproducts of ATP breakdown (ADP
+ Pi) back together so muscular contractions can take place again. Here is where
the creatine comes in to play. The body has to hace creatine phosphate to force
the ADP + Pi back together to reform ATP for energy. Creatine phosphate is
formed when a chemical reaction breaks down creatine monohydrate, a natural
dietary substance found in meats. The liver can synthesise creatine in small
amounts but most of the creatine we digest is stored in the muscles and bones
for future use. However, especially in diets low in protein, we do have limited
stores and it does take time to release the creatine stores. Red meat is the
best source of creatine,however there is only about 1 g./lb. of meat. By taking
creatine supplements you are supersaturating the body with creatine phosphate
stores. This will enable you to have more creatine available to produce more ATP
at a faster rate. Thus, more energy is available per muscular contraction and
ATP stores are restores quicker. This means for weight lifters more max strength
and quicker recovery. The instructions for supplementation: 1st 5 days: 5g.4-6 x
per day (this is the loading phase) after: 5-8g 30-45 min before workout/ 5g.
after workout. Creatine supplements will also cause, in most individuals intra
cellular fluid retention. I have experienced 10 lb weight gains in first 2 wks.
You should also start experiencing strength gains after the first week. These
gains wont be dramatic, like steriods, but you will see a difference. Try it , I
think you will like it. Texas A&M experimented with it with a few players
last season. This season they are putting the whole team on it because they got
such positive results with the few guys who tried it. promote further gains in
sprint performance (5-8%), as well as gains in strength (5-15%) and lean body
mass (1-3%). The only known side effect is increased body weight. More research
is needed on individual differences in the response to creatine, periodic or
cyclical use of creatine, side effects, and long-term effects on endurance.
Reviewers' comments Introduction Creatine is an amino acid, like the building
blocks that make up proteins. Creatine in the form of phosphocreatine (creatine
phosphate) is an important store of energy in muscle cells. During intense
exercise lasting around half a minute, phosphocreatine is broken down to
creatine and phosphate, and the energy released is used to regenerate the
primary source of energy, adenosine triphosphate (ATP). Output power drops as
phosphocreatine becomes depleted, because ATP cannot be regenerated fast enough
to meet the demand of the exercise. It follows that a bigger store of
phosphocreatine in muscle should reduce fatigue during sprinting. Extra creatine
in the muscle may also increase the rate of regeneration of phosphocreatine
following sprints, which should mean less fatigue with repeated bursts of
activity in training or in many sport competitions. So much for the theory, but
can you get a bigger store of creatine and phosphocreatine in muscle? Yes, and
it does enhance sprint performance, especially repeated sprints. Extra creatine
is therefore ergogenic, because it may help generate more power output during
intense exercise. In addition, long term creatine supplementation produces
greater gains in strength and sprint performance and may increase lean body
mass. In this article I'll summarize the evidence for and against these claims.
I'll draw on about 42 refereed research papers and four academic reviews to make
conclusions regarding the ergogenic value of creatine supplementation. In
addition, I'll provide 25 references to studies published in abstract form,
which report the most recent preliminary findings on creatine supplementation.
Effects of Creatine Supplements on Muscle Creatine, Phosphocreatine, and ATP The
daily turnover of creatine is about 2 g for a 70 kg person. About half of the
daily needs of creatine are provided by the body synthesizing creatine from
amino acids. The remaining daily need of creatine is obtained from the diet.
Meat or fish are the best natural sources. For example, there is about 1 g of
creatine in 250 g (half a pound) of raw meat. Dietary supplementation with
synthetic creatine is the primary way athletes "load" the muscle with
creatine. Daily doses of 20 g of creatine for 5-7 days usually increase the
total creatine content in muscle by 10-25%. About one-third of the extra
creatine in muscle is in the form of phosphocreatine (Harris, 1992; Balsom et
al., 1995). Extra creatine in muscle does not appear to increase the resting
concentration of ATP, but it appears to help maintain ATP concentrations during
a single maximal effort sprint. It may also enhance the rate of ATP and
phosphocreatine resynthesis following intense exercise (Greenhaff et al., 1993a;
Balsom et al., 1995; Casey et al., 1996). There is some evidence that not all
subjects respond to creatine supplementation. For example, one study reported
that subjects who experienced less of a change in resting muscle creatine (*20
mmol/kg dry mass) did not appear to benefit from creatine supplementation (Greenhaff
et al., 1994). However, more recent studies indicate that taking creatine with
large amounts of glucose increases muscle creatine content by 10% more than when
creatine is taken alone (Green et al., 1996a; Green et al., 1996b).
Consequently, ingesting creatine with glucose may increase its ergogenic effect.
Effects on Performance Researchers first investigated the ergogenic effects of
short-term creatine loading. In a typical study, a creatine dose of 5 g is given
four times a day for five to seven days to ensure that muscle creatine
increases. A control group is given a placebo (glucose or some other relatively
inert substance) in a double-blind manner (neither the athletes nor the
researchers doing the testing know who gets what until after the tests are
performed). Most studies have shown that speed or power output in
sprints--all-out bursts of activity lasting a few seconds to several minutes--is
enhanced, typically by 5-8%. Repetitive sprint performance is also enhanced when
the rests between sprints don't allow full recovery. In this case, total work
output can be increased by 5-15%. There is also evidence that work performed
during sets of multiple repetition strength tests may be enhanced by creatine
supplementation, typically by 5-15%. In addition, one-repetition maximum
strength and vertical-jump performance may also be increased with creatine
supplementation, typically by 5-10%. The improvement in exercise performance has
been correlated with the degree in which creatine is stored in the muscle
following creatine supplementation, particularly in Type II muscle fibers (Casey
et al., 1996). Researchers have now turned their attention to longer-term
creatine supplementation. In these studies, a week of creatine loading of up to
25 g per day is followed by up to three months of maintenance with reduced or
similar dosages (2-25 g per day). Training continues as usual in a group given
creatine and in a control group given a placebo. Greater gains are now seen in
performance of single-effort sprints, repeated sprints, and strength (5-15%).
Table 1 at the end of this article lists the references to positive effects of
creatine on performance. Theoretically, creatine may affect performance through
one or more of the following mechanisms (Table 2): an increase in concentrations
of creatine and phosphocreatine in resting muscle cells; an increased rate of
resynthesis of phosphocreatine between bouts of activity; enhanced metabolic
efficiency (lower production of lactate, ammonia, and/or hypoxanthine); and
enhanced adaptations through higher training loads. Creatine supplementation
during training may also promote greater gains in lean body mass (see Body
Composition below). Not all studies have reported ergogenic benefit of creatine
supplementation (Table 3). In this regard, a number of equally well-controlled
studies indicate that creatine supplementation does not enhance: single or
repetitive sprint performance; work performed during sets of maximal effort
muscle contractions; maximal strength; or, submaximal endurance exercise. What's
more, one study reported that endurance running speed was slower, possibly
because of an increase in body mass (Balsom et al., 1993b). In analysis of these
studies, creatine supplementation appears to be less effective in the following
situations: when less than 20 g per day was used for 5 days or less; when low
doses (2-3 g per day) were used without an initial high-dose loading period; in
crossover studies with insufficient time (less than 5 weeks) to allow washout of
the creatine; in studies with relatively small numbers of subjects; and when
repeated sprints were performed with very short or very long recovery periods
between sprints. It is also possible that subject variability in response to
creatine supplementation may account for the lack of ergogenic benefit reported
in these studies. In addition, there have been reports that caffeine may negate
the benefit of creatine supplementation (Vandenberghe et al., 1996).
Consequently, although most studies indicate that creatine supplementation may
improve performance, creatine supplementation may not provide ergogenic value
for everyone. Body Composition Although some studies have found no effect, most
indicate that short-term creatine supplementation increases total body mass, by
0.7 to 1.6 kg. With longer use, gains of up to 3 kg more than in matched control
groups have been reported (see Table 4 at the end of this article for
references). For example, Kreider et al.(1998) reported that 28 days of creatine
supplementation (16 g per day) resulted in a 1.1 kg greater gain in lean body
mass in college football players undergoing off-season resistance/agility
training. In addition, Vandenberghe et al. (1997) reported that untrained
females ingesting creatine (20 g per day for 4 days followed by 5 g per day for
66 days) during resistance training observed significantly greater gains in lean
body mass (1.0 kg) than subjects ingesting a placebo during training. The gains
in lean body mass were maintained while ingesting creatine (5 g per day) during
a 10-week period of detraining and in the four weeks after supplementation
stopped. Findings like these suggest that creatine supplementation may promote
gains in lean body mass during training, but we don't yet understand how it
works. The two prevailing theories are that creatine supplementation promotes
either water retention or protein synthesis. More research is needed before we
can be certain about the contribution each of these processes makes to the
weight gain. Side Effects In studies of preoperative and post-operative
patients, untrained subjects, and elite athletes, and with dosages of 1.5 to 25
g per day for up to a year, the only side effect has been weight gain (Balsom,
Soderlund & Ekblom, 1994). Even so, concern about possible side effects has
been mentioned in lay publications and mailing lists. Before discussing these
possible side effects, it should be noted that they emanate from unsubstantiated
anecdotal reports and may be unrelated to creatine supplementation. We must be
careful to base comments regarding side effects of creatine supplementation on
factual evidence, not speculation. But we must also understand that few studies
have directly investigated any side effects of creatine supplementation.
Consequently, discussion about possible side effects is warranted. Anecdotal
reports from some athletic trainers and coaches suggest that creatine
supplementation may promote a greater incidence of muscle strains or pulls.
Theoretically, the gains in strength and body mass may place additional stress
on bone, joints and ligaments. Yet no study has documented an increased rate of
injury following creatine supplementation, even though many of these studies
evaluated highly trained athletes during heavy training periods. Athletes
apparently adapt to the increase in strength, which is modest and gradual. There
have been some anecdotal claims that athletes training hard in hot or humid
conditions experience severe muscle cramps when taking creatine, and the cramps
have been attributed to overheating and./or changes in the amount of water or
salts in muscle. But no study has reported that creatine supplementation causes
any cramping, dehydration, or changes in salt concentrations, even though some
studies have evaluated highly trained athletes undergoing intense training in
hot/humid environments. In my experience with athletes training in the heat
(e.g., during 2-a-day football practice in autumn), cramping is related to
muscular fatigue and dehydration while exercising in the heat. It is not related
to creatine supplementation. Nevertheless, athletes taking creatine while
training in hot and humid environments should be aware of this possible side
effect and take additional precautions to prevent dehydration. Some concern has
been raised regarding the effects of creatine supplementation on kidney
function. The body seems to be able to dispose of the extra creatine without any
problem (Poortmans et al., 1997). The extra creatine is eliminated mainly in the
urine as creatine, with small amounts broken down and excreted as creatinine or
urea. No study has shown that creatine supplementation results in clinically
significant increases in liver damage or impaired liver function. It has also
been suggested that creatine supplementation could suppress the body's own
creatine synthesis. Studies have reported that it takes about four weeks after
cessation of creatine supplementation for muscle creatine (Vandenberghe et al.,
1997) and phosphocreatine (Febbraio et al., 1995) content to return to normal.
It is unclear whether muscle the content falls below normal thereafter. Although
more research is needed, there is no evidence that creatine supplementation
causes a long-term suppression of creatine synthesis when supplementation stops
(Balsom, Soderlund & Ekblom, 1994; Hultman et al., 1996). Does creatine
supplementation have undiscovered long-term side effects? Trials lasting more
than a year have not been performed, but creatine has been used as a nutritional
supplement for over 10 years. Although long-term side effects cannot discounted,
no significant short-term side effects other than weight gain have been
reported. In addition, I am not aware of any significant medical complications
that have been linked to creatine supplementation. Furthermore, creatine and
phosphocreatine have been used medically to reduce muscle wasting after surgery
and to improve heart function and exercise capacity in people with ischemic
heart disease (Pauletto & Strumia, 1996; Gordon et al., 1995). Creatine
supplementation may even reduce the risk of heart disease by improving blood
lipids (Earnest, Almada & Mitchell, 1996; Kreider et al., 1998). On the
basis of the available research, I consider creatine supplementation to be a
medically safe practice when taken at dosages described in the literature.
Determining whether creatine supplementation has any short- or long-term side
effects is an area receiving additional research attention. If there are side
effects from long-term creatine supplementation, an important issue will be the
liability of coaches, trainers, universities, and athletic governing bodies who
provide creatine to their athletes. Anyone advising athletes to take creatine
should make it clear that side effects from long-term use cannot be completely
ruled out, and that the athletes do not have to take the supplements. It would
be wise to have a formal policy for dosages to reduce the chances of athletes
taking excessive amounts. Ethics Creatine supplementation is not banned, but is
a nutritional practice that enhances performance nevertheless unethical? Anyone
pondering this question should consider that creatine supplementation is a
practice similar to carbohydrate loading, which is well accepted. Some are also
concerned that creatine supplementation could cause a carryover effect, whereby
athletes who have learned to take creatine are more likely to use dangerous or
banned substances. Proper education among athletes, coaches, and trainers
regarding acceptable and unacceptable nutritional practices is probably the best
way to reduce any carryover. How to Use Creatine A typical loading regime for a
70-kg athlete is a 5-g dose four times a day for a week. Thereafter the dose can
be reduced to 2 to 5 g per day in order to maintain elevated creatine content.
This supplementation protocol will increase intramuscular creatine and
phosphocreatine content and enhance high intensity exercise performance. There
is now some evidence that taking glucose (100 g) with the creatine (5 to 7 g)
increases the uptake of creatine into muscle (Green et al., 1996a; Green et al.,
1996b). Consequently, I recommend that athletes take creatine with carbohydrate
(e.g. with grape juice) or ingest commercially available creatine supplements
that combine creatine with glucose. For athletes wanting to promote additional
gains in lean body mass, I recommend 15 to 25 g per day for 1 to 3 months.
Although many athletes cycle on or off creatine, no study has determined whether
this practice promotes greater gains in fat free mass or performance than
continuous use. More research is needed here. Creatine supplements are good
value. Creatine is now being sold for as little as US$30 per kg, or about $0.60
per day when taking 20 g per day. Popular sports drinks are more expensive.