Caffeine
Kelly Olsen looks at the effects of getting your daily shot
of caffeine on fitness.
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The Effects of Caffeine on Exercise Performance
By Kelly Olsen
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One look at the queue in your local coffee shop or coffee
machine at work will convince anyone that a huge amount of
coffee is consumed daily.
As one of the most widely used
stimulants in the world, caffeine occurs naturally in foods and
drinks, like tea, coffee and chocolate. It is also added to
medicines for colds, aspirin and weight loss products.
So a cup
of coffee may well get us going in the mornings and if we order
a ‘skinny’ latte we might feel even a little virtuous, but what
are the effects of getting your daily shots of caffeine on
fitness?
General Effects of Caffeine
Caffeine basically gives us a jolt and in the US it is
estimated that over 10% of people drink 10 cups per day.
In
scientific terms caffeine blocks adenosine which is a
neurotransmitter that normally has a calming effect on the body.
This causes adrenaline to be released which in turn raises your
heart rate, tightens your muscles, dilates your pupils and the
body releases extra glucose into your body for extra energy –
hey presto the caffeine buzz.
That’s not all, the pleasure
parts of your brain are also stimulated through the increase in
dopamine, which is the usual suspect for explaining why we
become addicted to caffeine.
Sounds good doesn’t it? The physiological affects of having
that cup of coffee makes you feel really energetic and alert
from the pumping of adrenaline around your body and the dopamine
is making you feel really good – have another espresso!
On the down side caffeine does have some side effects such as
irritability and being unable to sleep and high doses can cause
irregular heart beat.
Often people have been advised to avoid
caffeinated drinks prior to exercise due to its diuretic effect.
Most studies now show that unless taken in huge quantities, say
8 cups in one sitting, this is not the case. There has also been
some association with increased risk of osteoporosis in
postmenopausal women.
Does Caffeine Affect Exercise Performance?
Caffeine has no nutritional value and is referred to as a ‘nutritional
ergogenic aid’.
When it is ingested it is very quickly
absorbed by the body – usually within 1 – 2 hours.
Research by
the American College of Sports Medicine has shown that ingesting
3-9 mg per kilogram of body weight (2-6 cups of regular coffee)
approximately 1 hour before exercise can increase endurance or
help with short intense exercise (around 5 minutes) where the
person is working at near maximum.
The belief is that it has an
effect on muscle contraction during anaerobic exercise –
remember though this was tried on well-trained athletes in a
laboratory environment.
Studies on elite distance runners and
swimmers did show an increase in their performance times after
they had ingested caffeine. The Australian Institute of Sport
team found that caffeine triggers the muscles to start using fat
as an energy source rather than carbohydrate sugars.
Certainly the enhanced performance using caffeine has been
well documented and the Olympic Committee banned athletes from
having more that 12 mg/ml in their urine samples. This equates
to approximately 4 – 7 cups of coffee consumed within 30
minutes.
Why is Endurance Improved with Caffeine?
Well, it has not been proven, but the common explanation is
that endurance is improved although no studies have shown an
increase on caffeine’s
ergogenic effect on athletic performance, although habitual
caffeine drinkers experience less effect that people who do not
consume it regularly.
The common explanation to why endurance is improved with
caffeine is that muscle glycogen is spared, as once muscle
glycogen is depleted you cannot exercise to your full potential.
Glycogen sparing, caused by caffeine ingestion, helps stop the
body from using up all the glycogen in the muscles.
Is Coffee the Right Choice for a Pre-workout
Drink?
Simple answer is yes with a ‘but’.
A recent Canadian study
compared the effect of caffeine on running times and levels of
exhaustion. Nine men took part in five trials. 1 Hour before
each run the men took one of the following: A placebo, caffeine
capsules, de-caffeinated coffee with caffeine added, regular
coffee.
The results showed that the men taking the caffeine capsules
increased their performance by up to 10 times. Whilst the levels
of caffeine absorbed by all the men were the same during the
trail, the belief is that with coffee itself the other
ingredients and processes that form part of the roasting and
grinding of coffee beans interfere with caffeine’s
performance-enhancing effects, so caffeine capsules work better.
What About the Effects on Creatine?
Creatine is known to help with endurance and many people
take supplements to enhance their performance.
Studies show that
caffeine can completely counteract the effect of taking Creatine
supplements. Advice to people taking Creatine as a supplement is
to avoid caffeine found in food and drinks.
Conclusion…
Yes, caffeine could enhance your performance and some studies
suggest it is up to 60%. This is not a replacement for a healthy
diet and good hydration, all of which will definitely help you
train better and reach your fitness goals. |
