Transcript Document

PHYSICAL STRESS ON THE BODY USING A VO2
MAX TEST AND ITS EFFECTS ON SHORT-TERM
MEMORY IN MALE STUDENTS
Author: Kimberly Alvarez
Faculty Sponsor: Dr. Judy Wilson, Ph.D. Cardiovascular Research
Laboratory, The University of Texas at Arlington, Arlington, TX
Introduction
Methods (cont’d)
Research shows that rhythmic exercise changes in serotonin,
epinephrine, norepinephrine and acetylcholine levels all affect
cortical arousal and cognitive function (Potter & Keele, 2005).
There are many reasons why the brain is affected during exercise.
Some of these include: increased glucose, oxygen and nutrient
levels to the brain. Exercise has been shown to enhance cognitive
function in both short and long term memory. However, when the
body is put under a large amount of physical stress, less oxygen is
left in the brain due to the fact that the muscles require more of
that oxygen and glucose. Does this affect cognitive function?
Once the five minutes were up, the subject then took an elevenminute break in which they could ask questions. When the eleven
minutes were up they were then asked to repeat as many words as
they could recall. The subjects were given a day and time to come in
for day two of the study.
Purpose
The purpose of this study was to determine if an exercise test to
maximal exhaustion would be better at improving cognitive
function in active male students than sitting with no intervention.
Methods
For this study, eight males (M; age 23 + 2.83 yrs; wt. 77.15 + 9.92 kg; ht.
172.7+ 2.82 cm.) of the UTA Kinesiology department, volunteered to
participate in this study. Once recruited, the subjects were given a consent
form to sign and return on day one of the study. Each subject reported to
the Exercise Science Research Laboratories in the MAC on Day One and
returned their form. They were given an overview of what a VO2 maximal
exercise test was. They were shown all of the equipment necessary for the
test, which include a headpiece, a nose clip and a mouthpiece, which is
attached to the metabolic cart. The protocol that was used for the exercise
test was the Bruce Protocol performed on a treadmill. This protocol
involved stages where the speed and grade increased every three minutes.
After the overview of day two was given the subject was asked to have a
seat. A list of words from the Rey Auditory-Verbal Learning test, which
contained fifteen nouns, was given to the subject who then had exactly
five minutes to memorize the list.
Results (cont’d)
Age
Mean
Standard
Deviation
Minimum
Maximum
23
2.83
Weight Height
(kg)
(cm.)
77.15
172
9.9
8.8
20
29
67.27
97.72
64
74
BMI
25.7
3.68
22.5
31.6
Table 1: Demographics
When the subjects arrive for Day Two, they were given a heart rate
monitor to strap around their chest so that their heart rate could be
tracked throughout the test. Then, they were asked to memorize a
different list of words from the Rey Auditory-Learning Test and given
five minutes. When the five minutes were up they headed to the
treadmill where the necessary equipment shown on Day One was
given to each subject. After a three minute warm up, the Bruce
Protocol was started and their heart rate was taken every minute. At
the end of the third minute the speed and grade on the treadmill was
increased. A thumbs up meant that the subject was doing okay on the
treadmill while a thumbs down or shaking of the hand meant that the
subject had reached maximal exhaustion and had to stop the test.
After the subjects gave the final hand signal, their equipment was
taken off and they had a five-minute active recovery period. The
subjects were then asked to recall as many words as possible. When
they could no longer remember any additional words, the study was
concluded.
Results
The subjects’ height and weight were 77.15 ± 9.9 kg and 172 ± 8.8 cm.
Pre- memorization of words for Day One and Day Two were both 15 ± 0
and there was no significant difference (p > 0.05). However, the
difference in the post-memorization of words on Day One (14 + 0.76) and
Day Two (10.88 ± 3.14) was statistically significant (p = 0.010).
Day 1
Mean
Pre
Words
Post
Words
15
Standard
Deviation
0
14
0.76
P-Value
Day 2
Mean
Standard
Deviation
P-Value
0.0072
Pre
Words
Post
Words
15
0
0.0074
10.88
3.14
Table 2: Day 1 Pre and Post Words
Memorized
Post Words
Mean
Post Standard
Deviation
P-Value for
Day 1 and
Day 2 Post
Table 3: Day 2 Pre and Post Words
Memorized
Day 1 with 10
minute rest
period
14
Day 2 with a
VO2 Max Test
0.76
3.14
10.88
0.0101
Table 4: Day 1 and Day 2 Post Word Memorization
Conclusion
The results of this study indicate that a test to exhaustion had a
negative effect on cognitive function. This may be due to the level of
physical stress placed on the body resulting in an inability to focus on
the words previously memorized. With no intervention during the
interval on Day One, subjects may have been able to focus on the
words memorized which they were not able to do on Day Two. Using
another type of diversion in addition to exercise may help in
determining what might affect cognitive function.