The Effect of Caffeine on Mean and Peak Power Performance in an Anaerobic Wingate Test

RUNNING HEAD: THE EFFECT OF CAFFEINE ON MEAN AND PEAK POWER IN AN ANAEROBIC WINGATE TEST 1
The Effect of Caffeine on Mean and Peak Power
Performance in an Anaerobic Wingate Test
By: dd.
EXSC 340 - Advance Exercise Physiology
Australian Catholic University

The effect of caffeine on mean and peak power in an anaerobic Wingate test 2
Study Purpose
There is an abundance of scientific literature on show displaying the effects of caffeine and
its physiological response in exercise performance, both aerobic and to a less extent,
anaerobic. A meta-analysis on caffeine ingestion on anaerobic performance using the
Wingate across 16 studies, concluded that both mean power and peak power displayed a
significant increase upon ingestion of caffeine in comparison to placebo ingestion (Grgic,
2018). Although it is established that there is definitely an increase in anaerobic performance
through caffeine ingestion, most participants involved in these studies are of an elite level.
Moreover, little effort has been put into the non-elite category of this study, which gives an
identification of purpose in my study as the participants involved are at a non-elite level,
building on that, it is known that power output is most predictive in elite athletes (Lorenz,
Reiman, Lehecka & Naylor, 2013), however the results of the study should clarify that there
will be an increase in both mean and peak power followed by the intake of caffeine in a 30
second anaerobic Wingate test.
Expected Outcome
Astorino & Roberson (2010) found out that there is an increase in the force of skeletal muscle
contraction due to a large dose of supplementing with caffeine. They also found that caffeine
enhances the release of calcium from the sarcoplasmic reticulum membrane, without
affecting the rate of calcium reuptake. As a result, the potential for the binding of calcium to
troponin is much greater, resulting in an increase in actin-myosin filament cross bridging
which in turn will result in greater force production by the muscle.
It was expected that mean power performance would be improved upon the use of caffeine as
an ergogenic aid, as it is commonly used as a method to improve endurance amongst athletes.
Ribeiro & Sebastiao (2010) suggest that caffeine acts as an antagonist towards adenosine

The effect of caffeine on mean and peak power in an anaerobic Wingate test 3
receptors, meaning as it binds to the receptors, it halts the binding of adenosine, which
stimulates the central nervous system. This stimulation of the CNS has been shown to result
in the masking/delaying of fatigue during exercise. This masking of fatigue should allow for
prolonged performance, which should allow for an improvement in mean power
performance.
Previous studies in this area
A research was conducted by Woolf, Bidwell, & Carlson (2008) which tested the effects of
a supplement caffeine against a placebo supplement to determine the effects on factors of
performance as an ergogenic aid such as outputs of peak power. The research majorly aimed
at determining whether caffeine, as an ergogenic aid had an effect that is significant on the
output power by using a 30s Wingate test as a means of determining power output. The
research entailed 18 male athletes, with a mean BMI of 26.4 and a mean age of 24.1. The
athletes were brought in for testing twice in two occasion a week apart. The participants had
to fast 8-12 hours and abstain from products which had caffeine for 48 hours prior to the
testing. Prior to the test, the participants would either intake a caffeine (5.0mg/kg BW) or a
placebo supplement (carbohydrate, 0.125g/kg BW). The participants also had to partake in a
warm-up protocol which consisted of static and dynamic stretches. The participants began
their Wingate test after an hour from taking the supplement and cycled till they reached their
maximum speed. Resistance was set and they completed the maximum effort test for 30
seconds. The participants did this o both sessions with caffeine supplement on one of the
testing day and the placebo supplement on the other. The testing was completed in a double
blind formats so that there is no misinformation and also to increase the overall accuracy of
the testing. The study revealed that there was a significant improvement in the peak power in
the caffeine trial as opposed to the placebo trial as the caffeine supplement has a value of

The effect of caffeine on mean and peak power in an anaerobic Wingate test 4
0.024 when testing for the output of the peak power. On the other hand, testing for the mean
power output revealed that there was a high score in the caffeine stage though it seemed
negligible as there was an insignificant improvement with the p-vale (p = 0.110). The
caffeine trial had an overall improvement of 78% of the participants. Though these results are
not absolutely in line with the results that we had gathered, it still supports the hypothesis that
there is a significant in increase in peak power output due to the caffeine supplementation.
Grgic (2017) carried out a study with the aim of determining the effects of ingesting caffeine
on anaerobic power performance on a 30s Wingate test using the techniques of meta-analytic
statistical. 16 studies were found to meet the benchmarks with a collective number of 246
participants. Thus, a standardised mean differences (SMD) for mean and peak power outputs
were carried out throughout the study. The outcomes of the meta-analysis therefore showed
that there was a significant difference between caffeine trials and placebo trails output power
(p-value = 0.005). The output of the peak power revealed a significant difference between the
caffeine trails and the placebo trails (p = 0.006). The results presented therefore indicate that
ingestion of caffeine can enhance both the peak and the mean power output performed on the
Wingate test by an additional 3% and 4% respectively. The meta-analysis therefore adds on
to the current evident presented that caffeine consumption can improve the anaerobic
performance components.
Participants’ description
This research involved eight elite athletes between the ages of 20 to 24 with a mean age of
21.5 ± 1.2 years. This included eight males with a mean height of 179.13 ± 6.06cm and a
mean weight of 83.88 ± 14.54kg. No prerequisites were required to take part in this study and
those with any medical conditions or injuries were excluded from the experiment.
Variables