Caffeine and Marathon Runners: Effects on Performance and Ethical Implications

This report explores the effects of caffeine consumption on marathon runners' performance and ethical implications. It reviews relevant scholarly articles to discuss the importance of caffeine consumption in the athlete industry, how caffeine acts on the body, and the effects of caffeine on performance. The report also highlights the ethical implications of caffeine consumption and suggests a safe limit of caffeine consumption and forms of caffeine that improve performance.

Running head: CAFFEINE AND MARATHON RUNNERS
Marathon Runners and Caffeine Consumption
[How caffeine consumption affects the performance of Marathon runners]
Name of the student:
Name of the university:
Author note:

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Table of Contents
1) Introduction.................................................................................................................................2
2) Literature review (main body).....................................................................................................2
Importance of ‘Caffeine Consumption’ in Athlete industry........................................................2
How ‘Caffeine’ acts on the body.................................................................................................4
The effects of ‘Caffeine’ on performance...................................................................................6
3) Ethical implications.....................................................................................................................7
4) Conclusions.................................................................................................................................9
References......................................................................................................................................10

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1) Introduction
The report is aimed at identifying the effects of caffeine consumption on the marathon
runners. The findings of the study could be utilized by researchers for a better understanding of
the topic area. The ethical implications of the study should help the concerned legislative body
bring better caffeine consumption guidelines for the runners, medical practitioners, etc.
2) Literature review (main body)
Relevant scholarly articles will be used to review the research works done on the topic.
The findings of these reviews will help to give some closing remarks on the topic as well as
discuss the ethical implications of the study. At the end of the section, there will be a conceptual
framework showing the concepts being used in the section.
Importance of ‘Caffeine Consumption’ in Athlete industry
Lohsoonthorn et al. (2013) find that ‘Tea’ and ‘Coffee’ are widely used around the globe.
Both of these drinks contain caffeine as one of its pharmacologically active substances. The
research shows that caffeine is widely used by the adult population of the world especially in
North America and Europe. As opined by Byun et al. (2015), caffeine is both fat and water-
soluble it gets easily distributed in the body after absorption. The small intestine and the stomach
help to distribute it in the body. Also, due to its lipophilic nature, caffeine effectively crosses the
barrier between blood and brain.

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Mednick et al. (2008) apart from highlighting the numerous benefits of caffeine
consumption also takes into consideration the harms of consuming it. Caffeine as according to
Shakeel & Ramadan (2010) is a kind of drug that when taken excessively can result in caffeine
addicts. High doses of caffeine as found by Chaudhary et al. (2016) can result in serious health
issues like insomnia, respiration, restlessness, nervousness, increased heart rate, nausea, stomach
irritation and vomiting. In the opinion of Snel & Lorist (2011), sleep disorders in people
diagnosed with acquired immunodeficiency syndrome (AIDS) can become worse from high
doses of caffeine. Headache, chest pain, anxiety, agitation and ringing in the ears are some other
side effects of large doses of caffeine.
Lara (2010) finds the consumption of caffeine beneficial as it results in many health
benefits like reduces fatigue and drowsiness. It is also beneficial in exercise performance. The
research has shown that caffeine can increase muscular strength and improve endurance. Burke
(2008) supports the views of Lara (2010) by saying that even the most sensitive of the people
will find caffeine consumption useful in optimizing the performance. In the research of Hansen
et al. (2014), marathon runners may face reducing the supply of energy. On the other hand,
caffeine consumption at the start of a race competition like ‘Marathon’ can help be energetic
before and during the competition. Athletes, as researched by Lynn et al. (2018), would also
need it at the end of the marathon to get the energy kick.
Del Coso et al. (2013) say that it is becoming difficult to avoid caffeine on a marathon
race because of the energy kick it supplies to the body. Athletes need a huge energy supply in
shorter times, which is why caffeine is preferred to get that energy boost. According to Gurley,
Steelman & Thomas (2015), the consumption of caffeine is safe when used in moderation. It can
enhance the performance, which perhaps is a concern for many athletes. Tiller et al. (2019) add

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more layers to the facts of caffeine consumption by athletes. The authors say that caffeine can be
hugely effective if taken in combination forms such as with sports drinks or gum. Caffeinated
coffee, on the other hand, may affect the performance-boosting properties of caffeine. Santos et
al. (2019) disagrees to Gurley, Steelman & Thomas (2015) to some extent and says that the use
of caffeine is not recommended to athletes those on certain medications, with already existing
heart conditions, pregnant women.
How ‘Caffeine’ acts on the body
According to Foxe et al. (2012), caffeine constitutes chemical elements that close
resemblance of adenosine. Caffeine blocks adenosine receptors to effectively hinder its action. It
is such a chemical characteristic of caffeine that helps it in an immediate energy boost. As found
by Pak et al. (2018), adenosine takes its root in the human brain where it impasses to adenosine
receptors. These impasses result in drowsiness by slowing down the activity of nerve cells. As
per this article, athletes should use alternatives, which are medically certified and recognized as
an energy booster. These alternatives are needed to overcome the drowsiness effect of adenosine
and adenosine receptors. Kumar et al. (2018) argues the findings of Pak et al. (2018) by saying
that too much of the caffeine use will slow down the activity of nerve cells to a notable extent.
The problems like sleeplessness are then likely to occur.
In the opinion of Elmenhorst et al. (2007), adenosine is a neuromodulator located
centrally to the nervous system. Neural activity is affected when adenosine binds to its specific
receptors. It is when people feel sleepy. Adenosine as found by Boison, Chen & Fredholm
(2010), dilates the blood vessels to ensure an uninterrupted supply of oxygenation during sleep.

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Conversely, as obtained from the study of Ribeiro & Sebastiao (2010), caffeine counteracts the
sleepy property of adenosine to keep people energetic until a certain timespan. It is this
pharmacological characteristic of caffeine that makes it a preferred consumption option for those
who want instant energy. However, Lebre, Rocha & Balteiro (2019) disagrees to Ribeiro &
Sebastiao (2010) and says that even a moderate consumption of caffeine is not safe for those who
are not a regular caffeine user. Caffeine can boost up the performance of runners those who
consume it regularly. The new users of caffeine can face detrimental side effects of caffeine such
as headaches and jitteriness.
The research of Adeva-Andany et al. (2016) has shown that increased muscle glycogen
accumulation post-exercise affects the repair of muscle tissue. Aglycogen resynthesis is needed
to overcome the fatigue of prolonged exercises and prevent possible muscle damage from a poor
glycogen resynthesis. The findings of Roberts et al. (2010), when caffeine co-ingested with
carbohydrates (CHO) can limit the post-exercise muscle damage.
The research of Choi et al. (2010) has found that caffeine can mobilize intracellular
calcium. According to the research, caffeine can significantly enhance the calcium release from
the sarcoplasmic reticulum. It can also inhibit the uptake of calcium. This mechanism becomes
important during submaximal contractions when caffeine enhances the contractile force in
caffeine consumers, both habitual and non-habitual.
As researched by Beedie (2010), there is more than one mechanism to explain the
ergogenic effects of pharmacological substances. It goes true for caffeine as well. Caffeine might
affect both the skeletal muscle and the central nervous system (CNS). However, caffeine has a
potential downside that questions its credibility in terms of its ergogenic effects. Indeed, Beedie,
Coleman & Foad (2007) say that caffeine due to its diuretic properties can also exert ergolytic

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effects in the events of prolonged endurance. Moreover, excessive consumption of caffeine can
lead to tachycardia, restlessness and tremor. Khan et al. (2018) say that caffeine can be harmful
for the health of those with high blood pressure or heart conditions.
The effects of ‘Caffeine’ on performance
Geyer et al. (2011) say that caffeine does not just reduce fatigue, but also increase
alertness and the concentration level. It is because of these health effects of caffeine, athletes use
it as an ergogenic aid. The effect of caffeine on the performance of athletes has been observed
both for aerobic and anaerobic sports. However, the effect of caffeine is not evenly distributed
across a variety of consumers. According to this research, a moderate dose or lower doses can be
sufficient for trained athletes to perform. However, the number of doses will vary significantly
for other groups such as untrained athletes. Despite these benefits of caffeine for the runners, the
research of Mohamed & Tawfik (2018) finds potential health problems in caffeine consumption.
According to the authors, the use of caffeine can result in diarrhea.
In the opinion of Woolf, Bidwell & Carlson (2008), caffeine is being identified as the
best-tested ergogenic aids that boost up the energy level of an individual making him or her
highly productive for a certain time. Caffeine also helps athletes in training longer and harder.
Caffeine due to its chemical properties exerts its impact on the brain and stimulates it to think
clearer and concentrate harder.
According to Hodgson, Randell & Jeukendrup (2013), caffeine does have its effect on
endurance exercise and higher intensity exercise. Caffeine also affects performance and makes
the task easier compared to a task that is done without consuming caffeine. In the opinion of

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Goldstein et al. (2010), the effect of caffeine can be seen more on athletes. The research of Ganio
et al. (2009) says that there are few body factors such as Glycogen stores and Fat stores those
fuel the body uses. Muscle gets fueled on utilizing the Glycogen; however, Glycogen stores get
depleted when the runner completes the race without using any alternative to replenish its
glycogen stores. Caffeine according to Spriet (2014) is one such supplement drink that athletes
can use to replenish and mobilize the Glycogen stores of the body.
As researched by Duncan & Oxford (2011), the human body has many fat stores than
Glycogen stores. While Glycogen is still there, the body can utilize its fat stores. Caffeine
supports the human muscles to use fat stores as fuel. This property of Caffeine is worth noting as
the human body has more fat stores compared to Glycogen stores. Indeed, the consumption of
caffeine is extremely beneficial for athletes as it helps to sustain energy levels for a longer
period. Caffeine other than its effects on the Glycogen stores and Fat stores of the human body
does significantly affect the human brain. Caffeine, as found in the research of Cappelletti et al.
(2015), stimulates the brain, keeping it away from mental fatigue and letting it concentrate more
on task goals. Gonçalves et al. (2017) argues the research of Duncan & Oxford (2011) and states
that caffeine itself does not supply any additional energy. It just helps people maintain work level
in a marathon run.
3) Ethical implications
Studies indicate that caffeine can also be harmful to human health. It can result in
numerous health diseases like high blood pressure, gout attacks, early death, insomnia,
incontinence, etc. A high dosage of caffeine can result in these health ailments. Moreover, the

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effect of caffeine on the performance of athletes varies from one to another athlete. Few athletes
can perform well on a moderate usage of dosage whereas many others cannot.
The research has few ethical implications such as dosage limitations on athletes and the
adult population of the world to avoid negative health effects of caffeine as much as is possible.
A moderate dosage of caffeine should only be allowed considering the negative health impacts of
a high dosage of caffeine. A moderate dosage is sufficient to perform well in the Marathon.
Another ethical implication can be a ban on caffeine consumption. Caffeine consumption
48-72 hours before the competition should be stopped to prevent any athlete from taking
advantage of such lenient governance Mohr, Nielsen & Bangsbo (2011). The limitation of time
will ensure that no athlete has an unfair advantage on the day of the Marathon competition.
Moreover, the findings of the research should matter to those who use caffeine regularly. These
people should know the safe limit of caffeine consumption, so that, their addict to caffeine does
not affect their health. Nevertheless, the research has shown that there are numerous health
impacts of caffeine such as restlessness, insomnia, etc. (Peacock, Martin & Carr, 2013).
People should also know the forms of caffeine that improve performance. Caffeine can be
consumed through coffees, teas, gels, pills, sodas, teas, gums and shots. The research has found
that the use of gums can be useful. Also, the manufacture of gels contains many elements such as
caffeine. Caffeine in the form of gels is easily available to athletes nowadays. Gums can also be
used; however, the most effective of this should be using it in combination with a health drink.
Caffeine in the form of a health drink can mobilize the muscle, and replenish the loss of Fat
stores and Glycogen stores (Hodgson, Randell & Jeukendrup, 2013).

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The testing of caffeine on individuals should also be the research implication. The
research has found differences in individuals about the performance effect of caffeine. Few
athletes are okay with just a moderate dosage. However, many others may require a
comparatively higher dosage. The best way to identify the limit is to conduct the training.
Caffeine needs to be tested in the training. The test should be conducted both before and during
the race. This test will help assess the individual response.
4) Conclusions
On a concluding note, it can be said that the consumption of caffeine can improve the
performance of athletes in the Marathon race. Caffeine will make them feel energized and better
prepared to cover the entire run without any loss of muscle damage. Caffeine improves
performance by stimulating the brain to help it focus more on one activity. Caffeine can be very
useful in the replenishment of wasted Glycogen stores and Fat stores. Glycogen stores and Fat
stores can be regained from caffeine consumption. The study has identified a few ethical
implications of the research. There should be a ban on caffeine consumption a few hours before
the competition to reduce its adverse health effects. Moreover, caffeine should be tested in
training to identify individual responses.

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