| Does
Gender Affect Exercising and Resting Pulse Rates in 7th Graders? |
Researched by Katlin
T.
2003-04 |
|
PURPOSE
The purpose of this
experiment was to determine the difference in exercising and resting heart
rates of 7th grade boys vs. 7th grade girls.
I became interested
in this idea because I have been interested in the medical field as a possible
career. I have always wondered if resting or exercising individuals would
have a greater heart rate.
The information gained
from this experiment could benefit coaches, parents, and doctors so they
know what to expect from 7th graders.
HYPOTHESIS
My first hypothesis
was that the heart rate would be greater after exercising than resting.
I based this on observation of my own pulse during exercise.
My second hypothesis
was that the heart rate for girls would be greater than the boys while
resting. I based this on The World Book Encyclopedia which stated,
“A person’ size largely determines a person’s resting heart rate. The bigger
a person is, the slower the heart rate.”
My third hypothesis
was that after exercising the heart rate for girls would be about the same
as the heart rate for boys. This was based on a passage in The World
Book Encyclopedia that said,”… usually the average person’s heart rate
is about the same, 72 beats per second.”
EXPERIMENT
DESIGN
The constants in this
study were:
* Boys’ and girls’
ages (12-13 years)
* The room temperature
* The room and equipment
* The exercise type
and exercising time
* The rest and the
resting time
* The method of taking
heart rate
* The time of taking
the heart rate (15 seconds)
The first manipulated
variable was whether the subject had rested or exercised.
The second manipulated
variable was the gender of the subject.
The responding variable
was the heart rate.
To measure the responding
variable I took the pulse for 15 seconds.
MATERIALS
QUANTITY
ITEM DESCRIPTION
15
boys
15
girls
2
step- up benches used for step aerobics
2
stopwatch
2
chair
1
metronome
PROCEDURES
1. Obtain the subjects
by having them get a signed parent permission slip.
2. Have one student
at a time come to the testing location.
3. Have the subject
rest in a chair for three minutes while the instructions are given.
4. Take the pulse
of the subject on the left wrist for fifteen seconds and record on the
data table.
5. Have the subject
rest for two more minutes.
6. Check the pulse
of the subject for fifteen seconds and record on the data table.
7. Now, have the subject
exercise on an 8-inch step bench for three minutes at a tempo of 100, which
would be 25 full step up/ step down motions using both feet per minute.
8. Check the pulse
and record on the data table.
9. Have the subject
exercise for three more minutes as in step 7.
10. Check the pulse
and record on the data table.
11. Have the student
return to class.
RESULTS
The original purpose
of this experiment was to determine the difference in exercising and resting
heart rates of 7th grade boys vs. 7th grade girls.
The results of the
experiment were that the heart rate was greater after exercising than resting.
I also found out that the heart rate for girls was greater than boys while
resting. I finally found out that immediately after exercising the heart
rate for girls was greater than boys.
See the table and graph
below.
CONCLUSION
My first hypothesis
was that the heart rate would be greater after exercising than resting.
My first hypothesis was accepted because the average after resting was
189 and the average after exercising was 251.
My second hypothesis
was that the heart rate for girls would be greater than the boys while
resting. My second hypothesis was rejected because the girls average for
resting was 189 and boys average for resting was 189.
My third hypothesis
was that after exercising the heart rate for girls would be about the same
as the heart rate for boys. My third hypothesis was accepted because after
exercising the girls average was 253 and after exercising the boys average
was 249.
Because of the results
of this experiment, I wonder if the exercising and resting pulse rates
would be different 7th graders and 3rd graders or 7th graders and 12th
graders.
If I were to conduct
this project again I would have tested many more subjects. I also would
have used an electric heart monitor to improve the pulse accuracy.
Research
Report
Heart
The heart is a hard working
pump whose action sustains life. Each beat sends blood throughout the body
to carry oxygen and food all over to the body’s cells. The beating of the
heart begins seven months before birth. When the heart stops, we die.
The heart is a large
hollow organ divided into the left and right sides that pump at the same
times. The veins collect blood from the body and carry it to the right
side of the heart. The ventricles pump the blood to the lungs, where it
picks up oxygen. Then, the oxygenated blood flows to the left side of the
heart, which pumps it through the arteries to the rest of the body. Valves
control the flow of blood throughout the heart.
The division of the
nervous system called the autonomic nervous system regulates the heart
and blood vessels. This automatic system controls your body’s activities
that are performed automatically without conscious control. The heart’s
rate increases and decreases, depending on your body’s needs. The heart
pumps slowly while a person is sleeping, providing small amounts of oxygen
to the resting body. The heart can then speed up and increase oxygen supplies
when the person exercises.
Various diseases can
strike any part of the heart. Although the death rate has fallen, disorders
of the heart and blood vessels remain the leading cause of death in the
United States and many other countries. Most common heart diseases narrow
arteries that supply the heart with blood and oxygen. The deposits and
fatty materials gradually build up and block these arteries.
The heart lies between
the lungs, about in the middle of the chest. People’s heart is a little
larger than their fist. A newborn heart weighs about 2/3 of an ounce, which
is approximately nineteen grams. An adult heart weighs from nine to eleven
ounces. That is equal to about 255 to 312 grams.
A membrane called the
epicardium covers the outside surface of the heart. The pericardium, another
membrane, surrounds the epicardium. The pericardium encloses the heart
completely. It also extends above the blood vessels that emerge from the
top of the organ. A slimy liquid between the epicedium and the pericardium
lubricates the heart and enables it to contract smoothly.
Circulatory
System
On average, the body has
about 5 liters of blood in the circulatory system. The heart, lungs, and
blood vessels work together to form the circulatory system.
Parts
The body’s circulatory
system has three parts: pulmonary circulation, coronary circulation, and
systemic circulation. They are also known as the lungs (pulmonary), the
heart (coronary), and the rest of the system (systemic). Each must work
independently in order for them to work together.
The circulatory system
is responsible for transporting materials throughout the body. It gives
nutrients, water, and oxygen to the body’s cells and carries wastes away,
such as carbon dioxide.
Pulse
A stretching of the arteries
that takes place after each heartbeat causes the pulse. It can be taken
or felt by placing the fingers on their wrist above the thumb at a point
over the radial artery. The other pulse can be felt by touching the temples
where the temporal artery is located, and at other places in the body where
an artery is near the surface.
Each heartbeat consists
of a contraction of the muscles of the heart that propels the blood into
the arterial system, followed by a period of time that is used for relaxation
while the heart refills. As the heart contracts, the blood is pumped in
to the aorta and pulmonary arteries. The aorta, which is the largest artery
in the body, carries the blood aerated by the lungs. Its elastic walls
are stretched and it expands to make room for the blood. As the blood moves
on to enter the arteries that branch off from the aorta, the walls relax
and it contracts to normal size. The walls of the arteries and of their
branches also expand and contract as the blood passes through them. The
expansion of these arteries causes the pulsation known as the pulse.
Pulse
Rate
The pulse rate of children
is faster that older people which is often slower than that of the average
healthy adult. Pulse rates between 50 and 85 per minute are considered
within normal limits. The normal rate for an average man is about 72, while
women’s is 76-80. The pulse rate of a newborn child can be as high as 140
per minute. The normal rate for a seven- year- old is about 90. A slower
pulse rate of 50 to 65 is not unusual in elderly people. Regardless of
a person's age the pulse and heart rhythm should be regular.
Exercise
A successful exercise
involves frequent physical activity that is rhythmic, repetitive, and challenges
the circulatory system, and uses your large muscles. Exercise must significantly
increases the blood flow to the muscles for a certain amount of time promoting
cardiovascular fitness, which is also known as iconic, dynamic, or aerobic
fitness.
Aerobic activities
get the blood pumping. As the heart beats faster, the blood circulates
more quickly, giving more oxygen to our muscles.
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BIBLIOGRAPHY
Abel, Francis L “ Circulatory
System.” The World Book Encyclopedia. 1998.
Avraham, Regina. The
Circulatory System New York: Chelsea House Publishers, 1989. pp:1-110
Crawford, Michael H
“Heart.” The World Book Encyclopedia. 1998.
Galperin, Anne. Strokes
and Heart Diseases New York: Chelsea House, 1991. pp: 1-107
Silverstein, Alvin.
The Circulatory System New York: Twenty First Century Books,1994. 1-96
Silverstein, Alvin.
The Respiratory System New York: Twenty First Century Books,1994. 1-94 |
ACKNOWLEDGEMENTS
I would like to thank
the following people for helping make my project possible:
* My parents for helping
me out through the year with transportation and much more.
* Human subjects for
helping me in the experiment and doing my experiment.
* Teachers for letting
their students come out of class to do the experiment.
* Mr. Newkirk and
Mrs. Helms for helping me with everything! I really appreciated it.
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