Volume 6, Spring 2008 - Saddleback College

Fall 2007 Biology 3A Abstracts
to their body weight, for the control factor. For a three
hour period, the participants worked on study material
to expend their energy on mental stress to achieve total
exhaustion, in order to simulate the working day of the
average American. During this time, their reaction
times were recorded at every 15 minute interval using a
reaction time ruler (accurate to ± 12.5 ms). This
process was repeated for the energy drink and diet
energy drink trials on different days for the same six
individuals; each individual had to consume equal
volumes of the afore mentioned drinks as they did
during the water trials.
Results
All data in this experiment will be given in
the form of the MEAN ± the standard error. The
average time of crashing from consumption for the
water trial was 1.54 ± 0.18 hours. The average time of
crashing from consumption for the sugar energy drink
trial was 1.50 ± 0.23 hours. The average time of
crashing from consumption for the diet energy drink
trial was 1.71 ± 0.22 hours.
Reaction Time
(ms)
250
200
150
100
50
0
R 2 = 0.2473
0:15
0:30
0:45
1:00
1:15
1:30
1:45
2:00
2:15
2:30
2:45
3:00
Time (hours)
Figure 1. This chart shows the average trend of reaction
times throughout the 3-hour period. High peaks in this graph
indicate times of exhaustion and low peaks in this graph
indicate times of alertness. The solid black line is the best fit
line for the water trial (control factor).
Time from Consumption
(hours)
2.5
2
1.5
1
0.5
0
Water Rockstar 1 Diet Rockstar
Selected Drinks
Water Trial
Sugar Energy Drink Trial
Diet Energy Drink Trial
Linear (Water Trial)
Figure 2. This graph displays the average time to reach
mental exhaustion from start of consumption for all drinks.
Error bars represent the standard error in the data for each
group.
75
Saddleback Journal of Biology
Spring 2008
In the previous graph above, the chi squared
value for the closeness in relationship between the
control factor and its linear trendline is 0.2473,
indicating high variation between the average trendline
and its data. The average times of crashing after
consumption were not found to be significantly
different between both sugar energy drink and diet
energy drink trials (p = 0.28, one-tailed, paired t-test).
There are no statistical differences in the three groups
(ANOVA, single factor, p = 0.76).
Discussion
According to the statistics, there were no
significant differences between the sugared drink and
diet drink trials, indicating that the monosaccharides do
not play a major role in the mental exhaustion due to
crashing. The major contributor to the body’s
exhaustion must be the caffeine. This confirms the
finding made by Lavin et al (1997) that sugar
consumption does not influence the body’s energy
metabolism, even though the study was primarily
focused on the effect of sugar itself without the
participation of caffeine.
Caffeine must be depriving the body’s energy
by high ATP and GTP utilization. According to the
findings of a previous study, caffeine is found to
increase the amount of inositol triphosphate in heart
muscle, but it does not seem to activate a higher
calcium current (Parker and Ivorra, 1991). Thus the
caffeine is wastefully consuming energy abundant ATP
and GTP for the increase in the concentration of
inositol triphosphate with no added effect on the action
of calcium ions to stimulate further cellular actions.
And more ATP is consumed as caffeine stimulates the
action of epinephrine to increase the heart rate. This is
one reason for the crash.
However, the ANOVA test showed that all
three groups were not different from each other (p =
0.76). This arises some question as to why the data
from the water trial was not different from the energy
drink trials. The reason for this may be in a high
amount of variation amongst the human population, a
very small population size, especially for human
subjects, and possibly insufficient metabolism of
energy through mental stress, as was required for this
experiment. This could explain why the chi squared
value for the baseline average of the water trial was so
low. In other words, the water group was already
energy deprived from the start because the individuals
were asked not to eat anything before starting the
experiment, so the data fluctuates due to their hunger.
In the other two groups, the test subjects may not have
been studying to the full extent that they were
instructed, which conserves their energy output. In