Caffeine is a
central nervous system stimulant of the methylxanthine class. Caffeine is
considered a psychotropic substance. This means it acts primarily on the CNS
and alters the brain. It is the world’s most commonly consumed psychotropic
substance/drug. Caffeine, unlike many other psychoactive substances, it is
legal and unregulated in most parts of the world. There are several known
mechanisms of action to explain the effects of caffeine. How it works is that
it blocks the effects of adenosine on its receptor and ultimately prevents
drowsiness that would have been the onset of adenosine attaching to its
receptor2. Caffeine also can stimulate certain parts of the
containing caffeine are consumed to relieve or prevent drowsiness and to
improve performance. To make these drinks, a process called infusion is used,
where the caffeine is extracted by steeping the plant in water.
Caffeine-containing drinks, such as coffee, energy drinks, and tea are popular.
About 85% of American adults consumed some form of caffeine daily, consuming
164 mg on average. Many people around the world use caffeine on a daily basis
because of its stimulant properties2. We use it in coffee to give us
a start to our day, or to give us a little boost at work midday. There are many
uses for caffeine, but the use for this particular research experiment will be
to see if the drug has an effect on anaerobic performance.
exercise is defined as short duration, high intensity exercise that last long
enough to lactate. This can be anywhere from 30 seconds to a few minutes.
Anaerobic exercise happens when your body’s need for oxygen exceeds the current
amount readily available in the body. So the body uses energy from elsewhere,
like the muscles. This type of exercise uses fast twitch muscle fibers for speed. It is used by athletes in non-endurance sports to
promote strength, speed and power and by body builders to build muscle mass. Anaerobic
exercise burns fewer calories than aerobic exercise, because the body builds up
lactic acid that causes the muscles to fatigue quickly. This is why anaerobic
actions cannot and do not last as long1,5.
in the laboratory has been closely related to field sprint performance in leading
cyclists, emphasizing that laboratory assessment of variables such as anaerobic
peak power and mean power provides meaningful data for evaluating and
Another aspect to
inspect in this research is the effect of caffeine on pain perception, and what
that can do to performance. Since adenosine receptors are blocked due to the
intake of caffeine there is a possibility that that pain receptors are blocked
as well. Caffeine is used in many over the counter pain relieving medications.
So if caffeine can block pain receptors, there is a theory that it could aid
when an athlete is training. The muscles in the body will be less likely to
feel the effect of the workout, and be less likely to fatigue quickly1,2,3,4.
A wattbike is a stationary bike that
will be used in the experiment. A wattbike is consistent to show how the average
power, fatigue, and cadence are affected by the consumption of caffeine. The
methodology behind the experiment will be that one group will cycle on the wattbike
for 30 second intervals, after the consumption of caffeine. The athlete’s power
and fatigue will be measured after each interval. There will also be a placebo
group where no caffeine will be ingested. The same aspects will be measured
within this group. The two will be compared. To get the best results and
averages, athletes of different strength, endurance, and size will need to be
studies have shown that with caffeine consumption has an effect on the catecholamine
response to high-intensity exercise. This was shown to increase adrenaline in
the body. An increase in ingestion of caffeine will presumably increase the
release of adrenaline. Adrenaline is consistent with endurance exercise as
well. If the amounts of adrenaline in the body rise, endurance and strength is
In a few of the studies it is also
shown that the presence of lactic acid is increased when caffeine is present in
the system. While other studies show that there is no increase in lactic acid
from the consumption of caffeine. Lactic acid is shown due to resting skeletal
The results from the anaerobic
performance are based off the groups of athletes cycling performance on the wattbike.
The group that consumed caffeine is compared to the placebo group. The findings
show that the effects of caffeine on anaerobic performance are minimal. It
depends on the individual’s level of endurance and strength. An elite cyclist
would be able to benefit off the effects of caffeine more so than a beginner
cyclist. The cadence of the athlete would depend on the height and speed of the
athlete, not just whether caffeine was consumed or not.
The minimal effects of caffeine on anaerobic
performance can be beneficial to those that use it sparingly to build muscle
mass and work on strength. For example, one study shows the amount of plasma
caffeine in the body compared to the length of exercise. The body can use high
doses of caffeine for endurance, but it eventually balances out to where there
is minimal, to no effect on the performance of the athlete. The table below
summarizes the findings of the studies.
Effect of caffeine on
Has minimal effect due
to the short duration of exercise
Effect on caffeine on
Blocks adenosine from
binding with receptor and causing drowsiness
Does the athletic
nature of individual play a role in whether caffeine helps in performance?
Trained or beginner
athlete may play a role in how much caffeine can help with performance
Caffeine blocks the
pain receptors. Does that affect performance?
There is evidence that
this may allow the muscles to continue and not fatigue so quickly
Does gender of the
athlete play a role on performance or cadence?
One study suggest that
sex would play a role in anaerobic performance, due to muscle mass,
regardless of caffeine intake.
CONCLUSION/ FURTHER DIRECTION
The effect of caffeine on anaerobic
performance is minimal. Research and experiments most likely depends on whether
a trained or an untrained athlete is used. When talking about high endurance
exercise caffeine has very slight effect due to its effects on the fast twitch
muscle fibers. For endurance training, slow twitch muscles are used more often.
Anaerobic exercise relies on energy sources that are stored in the muscles and,
unlike aerobic exercise, is not dependent on oxygen.
can be used to aid our bodies in working out
There are a couple of future
directions this research could take. One is the use of many different types of
athletes, with different body tones. This would give a wider range of data
regarding power and fatigue. Another aspect to note is another sport could be
used. The wattbike is an excellent piece of equipment to experiment the effects
of caffeine but would only be familiar to those who use it regularly, like
Another possible direction for the
research is to see if gender makes a difference on the performance. Men and women
have different body types, and muscle mass so this could cause a different
outcome on whether caffeine has an effect on performance. Men and women can
also have different cadences, meaning they step in quicker or slower paces. Males
are usually taller, so this would result in a quick and longer cadence,
compared to a female. Caffeine could also have an effect on this aspect of
cadence as well when using a certain gender. Although caffeine has a small effect, it still
could be used to increase anaerobic performance.