Saddleback Journal of Biology - Saddleback College

Fall 2009 Biology 3B Paper
The Effect of Aerobic Exercise on Human Short-Term Memory
Yousif Astarabadi and Hannah Ogren
Department of Biological Science
Saddleback College
Mission Viejo, CA 92692
Blood glucose has been shown to have a great impact on the enhancement of short
term memory in humans. In this study, glucose was used as a variable to test the hypothesis
that short term memory will increase after aerobic exercise. The hypothesis was assessed
by testing subjects with a memory test both before and after exercise, and by recording the
amount of number sequences recalled for both. Glucose was used a variable, so the
investigators tested the blood glucose levels of the participants before and after taking the
two memory tests. The average number sets recalled in the initial memory test prior to
exercise was 4.6 ± 0.476 (±SEM, n=10) and 7.3 ± 1.27 (±SEM, n=10) in the post exercise
memory test. A one tailed, paired t-test revealed that the number of sets remembered after
exercise is significantly greater than before exercise (p=0.003). An ANOVA test revealed
that there was no significance in the differences between the glucose levels (p=0.417).
However, there was significant evidence to support the claim that exercise increases shortterm
memory in humans.
Introduction
Whether it is doing homework, studying, or
taking a test, many news outlets report that students
should exercise because it will boost their
concentration, memory, and performance on everyday
school tasks. Short term memory is the ability to retain
a small amount of information for a brief period of
time. This can be important while studying because it
allows one to access the learned information while still
allowing them to input new information. This study
will investigate whether exercise has a significant
impact on short term memory.
Exercise is believed to increase short term
memory due to the fact that exercise naturally increases
blood glucose levels. Wahren et al, confirmed this in
their study by finding that “peripheral glucose
utilization increases in exercise despite a reduction in
circulating insulin levels…” Another study conducted
by Colombani et al (1996), found in their placebo test
that glucose levels increase after exercise. And
“glucose… can improve aspects of cognitive
performance…” (Scholey et al. 2004) Therefore, by
having the subjects exercise before taking a test, the
results should show that there was an increase in short
term memory.
To prove that memory increased the subjects
took a test and see if their results increased after
exercise. When a memory test was conducted by
Benton and Owens, the results showed, “There was a
significant correlation between blood glucose values
and the number of words recalled. Those whose blood
glucose levels were increasing remembered
significantly more words than those whose blood
glucose levels were falling.” This proves that the
glucose had a significant impact on the test outcomes.
Materials and Methods
The study was performed on November, 7,
2009, at 10:30 am in Laguna Niguel, California. Ten
participants were used in this study, five male and five
female, ages eighteen to twenty-two. They were chosen
based on their GPA’s of the previous semester and
their current study habits. All of the participants fasted
prior to participating and all of the participants were
hydrated before the study was started.
During this study, the participants took an
initial memory test with out having exercised or eaten
prior. Their blood glucose levels were taken and
recorded prior to the start of the memory test with a
Bayer One Touch Glucose Monitor. The area where the
blood was taken from was first sterilized with an
alcohol wipe. The finger was then pricked with a
lancet, and the first drop of blood was wiped away with
a cotton ball to prevent contamination. The memory
test consisted of a random number sequence of twenty
numbers, between two and four digits in length, and
was generated from a random number generator. The
participants had five minutes to memorize the test, and
after they finished studying they waited for five
minutes and then wrote down as many numbers as they
could recall for four minutes. After the test was taken
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Saddleback Journal of Biology
Spring 2010