Creatine supplementation has been shown in a number of studies to promote better gains in
lean body mass
and strength during resistance training compared to training alone.
The
primary way creatine supplementation works is by increasing muscle
creatine levels thereby enhancing muscle energetics. The primary form
of creatine used is
creatine monohydrate which is
water soluble and is transported into muscle by a specific transporter.
Several other creatine products have been developed that allege to
enhance the transport of creatine into muscle. One such product is
creatine ethyl esters
(CEE). Esters are compounds made from the combination of an alcohol and
a carboxylic acid. The idea behind "esterifying" creatine is that it
will change the physical properties of the compound making it more
stable and bioavailable. The hope is that an ester bond may protect the
compound from being digested in the gastrointestinal tract by typical
enzymes or it may increase its solubility so that it bypasses the
typical creatine transporter in muscle. Despite the claims, no study
had actually tested whether CEE worked better than creatine
monohydrate, until now. Researchers had 3 groups of untrained men
participate in a 7 week resistance training program with training
sessions 3x/wk. The groups supplemented with either creatine
monohydrate (CM), CEE, or placebo. Blood level of creatine were higher
with CM than CEE or placebo. Muscle levels of creatine were also higher
with CM after 7 days than both groups, but by 7 weeks the CEE group did
have an increase in muscle creatine but is was slightly lower than the
CM group. Blood creatinine (the breakdown product of creatine) was
higher in the CEE group indicating less
bioavailability.
The training program enhanced body composition and muscle strength, but
there were no differences between groups. The results show no
beneficial effect of CEE over creatine monohydrate on adaptations to
training. Since CEE was shown to increase the breakdown of CEE it
suggests a less efficient form of creatine and this was confirmed by a
lower muscle creatine level achieved with CEE. This is consistent with
earlier work in culture that showed a significant portion of the
creatine in CEE was converted to creatinine. The bottom line CEE does
not seem to live up to its claims and may be an inefficient form of
creatine compared to
creatine monohydrate.
Spillane
M, Schoch R, Cooke M, Harvey T, Greenwood M, Kreider R, Willoughby DS.
The effects of creatine ethyl ester supplementation combined with heavy
resistance training on body composition, muscle performance, and serum
and muscle creatine levels. J Int Soc Sports Nutr. 2009 Feb 19;6(1):6.
[Epub ahead of print]
