Alcohol (ethyl alcohol or ethanol),
one of the worlds oldest, most widely used, drugs, has many
effects on the body, some positive, but most negative.
Historically, alcohol has been blamed for many of the worlds
tragedies and problems, from the fall of the Roman Empire
(What's Your Poison; 1997) to the disbanding of many
families. Ironically, it is made from relatively innocuous
substances.
Fermented grain, fruit juice and honey have been used to
make alcohol for thousands of years. Alcohol's use spans
nationalities and demographics as it serves to relax and
provide a source of enjoyment. It has even been shown to
have some salutary effects, such as a blood thinning action
beneficial to the cardiovascular system, in addition to the
aforementioned social and relaxation aspects.
However, the doses required in these instances are very
minimal (1-2 glasses in most cases), and anything beyond
this more than outweighs any potential benefits. This is
partly because alcohol is classed as a central nervous
system depressant, causing the brain to relax and
inhibitions to decrease.
Ones rational thought, emotional status, judgment,
speech and muscle coordination are adversely affected
through alcohol consumption. In extreme cases it can cause
coma and death. Alcohol is specifically detrimental to
bodybuilders, or any athlete, in that it can interfere with recovery, protein
synthesis, hydration,
motivation, and
nutrient intake. Its financial cost is a burden for anyone
who buys it.
A review of the research will show that alcohol is
poisonous to every organ in the body and will adversely
affect everyone who engages in its use to some Extent. This article is not intended to dissuade people from
using alcohol moderately, for recreational purposes, but
will point out, from an athlete and a researchers point of
view, its significant shortcomings. Cheers.
Alcohol's Effects
Ethyl alcohol is a very small molecule which is soluble
in lipid and water solutions. It is metabolized primarily by
the liver, where an enzyme called alcohol dehydrogenase
breaks the alcohol down into acetaldehyde, which is further
broken down into acetate.
Acetate is metabolized into carbon dioxide and water,
which is excreted. Alcohol is absorbed rapidly from the
small intestine (80%) and stomach (20%), before any other
nutrients are digested.
These properties ensure that alcohol gets into the blood
stream and crosses the blood-brain barrier easily. Hence
alcohol's instantaneous effect on thought processes. In
fact, alcohol has a number of detrimental effects on the
brain two of which, central to the scope of this article,
will be discussed first.
Alcohol, once it has crossed the blood-brain barrier,
will inebriate the cerebral cortex (the part of the brain
responsible for executive functions such as rational
thought) and work its way down to the limbic system. It
won't however affect the limbic system. This turns out to be
a problem because the limbic system, being the most
primitive part of the brain, then takes over the role of
rational thought.
This is problematic because the limbic system is entirely
emotional, and one then begins to think with their emotions
rather than the rational area of their brain (the cerebral
cortex). A surprisingly small amount of alcohol will have an
instant effect on ones ability to control their emotions,
and their judgment as a result. A comparatively large
amount of alcohol and one might become violent or completely
out of control in other respects.
As mentioned, alcohol is also a depressant. It depressant
effect results from increased transmission of the GABA
systems. In other words, alcohol consumption creates a
demand for more GABA. GABA is a
neurotransmitter responsible for restricting, or depressing
the excitability of our brain. Glutamate is the
Neurotransmitter that has the opposite effect as it is
responsible for brain excitability and can be increased
through the intake of various stimulants. It now gets a bit
complex.
The post synaptic receptors (the receptors of one brain
cell that receive a message from another brain cell) for
GABA, GABA-A, then become stimulated and respond by
hyperpolarising the cell membrane and reducing the chance of
an action potential occurring. An action potential is an
electrical charge propagated through a neuron which causes
that neuron to become stimulated. It gets worse.
Over time, if a sufficient amount of alcohol is consumed,
the GABA receptors become accustomed to a certain amount of
alcohol and more is required to get the same depressing and
intoxicating effect. In short, tolerance occurs. With more
and more alcohol the potential for the GABA receptor to
function improperly increases. This may result in
hyperexcitability causing, anxiety, tremors, disorientation,
and hallucinations when one is not drinking.
This is alcohol at its destructive extreme.
In addition to alcohols destructive effects at the time
of ingestion, it can also cause neural tissue death when its
consumption is stopped. As explained, GABA (a inhibitory
neurotransmitter) binds to its GABA-A receptor following
alcohol intake. When this happens, a chloride channel is
opened and extracellular chloride moves into a intracellular
compartment on the receptor. The neuron is hyperpolarized as
a result and excitatory postsynaptic potentials (EPSPs)
cannot occur, as mentioned.
The main point here is that alcohol facilitates the
ability of GABA to open chloride channels. With greater
(chronic) use of alcohol the neuron may become entirely
dependant on alcohol for its GABA function in the long term.
However, at the time of chlorides uptake another process,
this time involving the glutamine (excitatory
neurotransmitter) receptors, causes further problems.
The glutamate system is up-regulated with alcohol
withdrawal and calcium-channel activity is stimulated.
Calcium is released directly onto the post synaptic neuron
(calcium influx) in large amounts and neural death occurs.
This happens particularly after binge sessions that occur on
a regular basis.
Implications For Athletes
Alcohol is particularly detrimental for
athletes as it
interferes with many of the processes so vital to success. Focus, performance, recovery and rebuilding are all
affected. Given that alcohol's effects can linger on for
days an athlete would be wise to refrain from its use when
competing.
Although alcohol is absorbed rapidly it is metabolized
very slowly and its effects may still impact athletic
performance up to 48 hours after the last drink.
Assuming the athlete is performing within 48 hours of its
consumption, as little as two to three standard drinks can
directly:
Decrease strength
Impair reaction time
