|
|
caffeine
The effects of caffeine on Recovery and performance
In my last article, I stated the importance of giving your body a period
of recovery from the process of recovery itself. I suggested taking at
least ten days off from any activity at some point over the fall or winter
before beginning your training for new season. In addition to that, I
suggested that if you were a coffee drinker, taking a break from your
daily ingestion of caffeine would be also be helpful. I thought taking
the time off the bike was going to be challenging for many of you, but
it turns out I received the most mail about coffee. Enough so that I thought
it warranted an article of its own.
The reason why it's important to try and lay off the coffee is of course
the caffeine. When you're taking time off the bike, as I said, the goal
is to allow your body to completely heal. You want to give it a break
from the stress on the hormonal systems, the releasing of adrenaline,
testosterone production, HGH production, etc. Caffeine is a stimulant
that affects the central nervous system, the importance of which has been
written about many times on Bike.com by coach Rick Crawford.
Caffeine in many ways is a wolf in sheep's clothing. It looks like adenosine
to nerve cells in the brain, so those cells welcome it with open arms.
Adenosine is a chemical that binds to adenosine receptors and causes drowsiness
by slowing down nerve cell activity, helping with normal sleep patterns.
Caffeine behaves much differently than adenosine, and speeds the cell's
activity up where adenosine would slow it down, putting the body into
a state of alert. This increase in activity sets off a chain reaction
in the body. The pituitary gland reacts by releasing hormones that cause
the adrenal gland to produce adrenaline. As a result, bronchial tubes
dilate to increase breathing, heart rate increases, blood pressure rises,
sugar is released into the blood stream, and your body generally prepares
for action.
The problem is, most of us aren't preparing for action with our morning
cup of coffee. We're simply trying to wake up. But again, caffeine is
a stimulant, and like most stimulants, it's addictive. The dose that might
give you a perk at one point becomes the dose you need just to get to
your base level. Caffeine increases dopamine levels in the same way that
amphetamines do. Dopamine is a neurotransmitter that activates the pleasure
center of the brain. In this way, caffeine works in the same way as heroin
and cocaine, albeit at much lower level. The manipulation of dopamine
levels in the brain is what likely powers caffeine addiction.
This relationship with caffeine can have longer-term effects that build
on themselves. Once the adrenaline wears off you have to pay that stimulant
debt back. In exchange for feeling extra peppy and happy, you feel tired
and grouchy for a while. Because caffeine can stay in your body well over
half a day, an afternoon cup will still leave you with some caffeine in
your blood stream at bed time, disrupting adenosine activity and depriving
you of quality sleep. You drink a morning coffee to get the adrenaline
going again, and the cycle begins.
Most people don't realize how much caffeine they ingest. A 6oz cup of
coffee has about 100mg of caffeine. When you see people walking out of
Starbucks with "venti" size drinks, it's absolute insanity.
A shot of espresso only has 50mg of caffeine, but in that case you're
only talking about 1oz of actual liquid. This is why espresso is such
a popular way to ingest caffeine as an ergogenic aid. A double shot of
2oz has as much caffeine as a full 12oz cup, (or a 200mg Vivarin tablet),
but in a more concentrated form.
The main intent of this article was to show the additional stress daily
caffeine has on your body, and the negative aspects of "running hot"
all the time. But what about caffeine as an ergogenic, or performance
enhancing substance? You can pull lots of articles up on PubMed <http://www.ncbi.nlm.nih.gov>
to prove or disprove pretty much anything you like, but it's good to do
some research there. Studies have shown caffeine, when consumed at about
3-10mg per kg of body weight, can increase endurance by prolonging time
to exhaustion, burn fat at a higher rate, lower perceived exertion, and
increase heart rate and alertness by stimulation the central nervous system.
At the same time, it may lower performance by working as a diuretic and
increasing dehydration. Caffeine is also banned in USOC regulated sports
like cycling at a level over 12 micrograms/milliliter of urine, which
translates to an average of about 4 cups of coffee or 2 Vivarin. Naturally
it varies on body size and hydration levels, so don't use me as your guide
for what constitutes cheating or not.
Clearly, if you're using caffeine on a daily basis just to make it through,
its ability to serve as an ergogenic is reduced. Additionally, if you're
impairing your ability to recover from training on a daily basis by putting
yourself through the ringer of caffeine addition, your performance and
fitness level will be impaired as well. And clearly, overuse of caffeine
on a hot day is not a risk work taking.
Coffee or caffeine in moderation each day might not be detrimental to
overall health, but it's still important for an athlete to understand
the effects of everything they put in their bodies in order to be able
to make informed choices. If you don't like the way you feel when you
take a day off from coffee or cola, perhaps that's your sign to consider
the hold it has on your body and mind.
|
