Press "Enter" to skip to content


Period 6
Science Fair Research
Title: ?
I have chosen to do this project because, as an athlete myself, I have wondered what affects pulse rate. When coming across this project, I though it interesting to figure out what the difference in pulse rate was between athletes and non-athletes. The purpose of my experiment is to figure out whether or not, after strenuous exercise, the pulse rates stabilize faster in athletes than non-athletes.

Pulse Rate
The pulse rate is the number of times a persons heart beats in one minute. This varies on a persons age and level of fitness. This is usually equal to the persons heart rate, unless there are problems of the heart. The pulse rate rises to meet the strain of an activity, and then stabilizes as you rest. The amount of increases and decreases in pulse rate and the speed of recovery increase as a person becomes more fit. A person between the ages of eight through fourteen should have an average pulse rate of eighty-four beats per minute. As a person gets older, the average stable pulse rate is becomes lower. When a person is a child, especially a newborn, the resting pulse rate is at its highest point.

A pulse is usually described in terms of its rate, which is the number of beats per minute (bpm). However, the rhythm and strength of the heartbeat can also be found, as well as whether the blood vessel feels hard or soft. A doctor should look at any irregular rhythms, weak pulses, or hard blood vessels found. It is not safe to put yourself through any physical exertion or exercise that increases the pulse rate beyond the normal limit. Pulse rate can be affected my many things. Certain medications, caffeine and cigarette smoking can affect the test of the pulse rate.
When you exercise, have a fever or are under stress, your heart rate speeds up to meet your bodys increased need for oxygen and nutrients that are carried in the blood. As a result of this, the pulse rate varies from minute to minute. The pulse rate is usually measured after a person has rested for ten minutes or longer, unless testing fitness level or in an emergency situation. This is called the resting pulse rate and is an accurate, simple test of the health of the heart and circulatory system.
There are also many factors that can produce abnormal resting heart rate. Some factors that cause pulse rates above normal are fever, stress, overactive thyroid glands, certain stimulants (which include caffeine, asthma medications, diet pills and cigarettes) and different forms of heard disease. Heart medications and also various forms of heart disease can cause pulse rates that are below the normal resting pulse rate. Fitness programs that involve aerobic exercise (running, swimming and fast walking) can gradually reduce the rate or your resting pulse rate.

A pulse rate can be tested by anyone. Putting pressure on an artery, on which pulsations can be felt, does this. The most commonly used artery is located on the forearm, just below the thumb. Pulse can also be felt behind the knee, on top of the foot, or in the neck, temple or groin. The average pulse rate for adults is between sixty and one hundred beats per minute, while a well-trained athlete can maintain an average of forty to sixty beats per minute. To find the maximum pulse rate, subtract your age from two hundred and twenty, and a healthy average rate is sixty to eighty percent of this.

There are many reasons pulse rates are measured. It can determine the health and function of the heart and also whether the heart is pumping enough blood. Pulse rate is used to test circulation in an injury or a part of the body with a blocked blood vessel. Doctors also use this to monitor certain medical conditions, or medications given to slow down the heart rate. An important reason pulse rate is measured is to test a persons overall health and physical fitness. Measuring your pulse rate at rest, during or immediately after exercise provides you with important information about your general physical condition.

Circulatory System
On average, your body has about five liters of blood continually traveling through it by way of the circulatory system. The heart, the lungs, and the blood vessels work together to form the circle part of the circulatory system. The pumping of the heart forces the blood through the veins, circulating it to the rest of the body. The circulatory system really has three distinct parts: pulmonary circulation (the lungs), coronary circulation (the heart), and systematic circulation (the other parts of the system). Each part must be working independently in order for them to all work together.
A blood vessel is defined as a hollow tube, which carries the blood throughout the body. There are three types of vessels: arteries, veins and capillaries. Arteries are tough on the outside and smooth on the inside and are made up of three layers. They contain an outer layer of tissue, a muscular middle and an inner layer of protective cells. The muscle walls of the artery help the heart pump blood. When the heart beats, the artery expands as it fills up with blood. When the heart relaxes, the artery contracts and pushes the blood along. When you take your pulse rate, you are actually feeling the artery expand and contract
The arteries deliver the oxygen-rich blood to the capillaries where the actual exchange of oxygen and carbon dioxide takes place. The capillaries then deliver the waste-rich blood to the veins where they are transported back to the lungs and heart.

Veins are similar to arteries but, because they transport blood at a lower pressure, they are not as strong as arteries. Like arteries, veins have three layers: an outer layer of tissue, muscle in the middle, and a smooth inner layer of protective cells. However, the layers are thinner and contain less tissue.
Veins receive blood from the capillaries after the exchange of oxygen and carbon dioxide has taken place. Therefore, the veins transport waste-rich blood back to the lungs and heart. It is important that the waste-rich blood keeps moving in the proper direction and not be allowed to flow backward. Valves, gates that only allow blood to move one way, that are located inside the veins can accomplish this.

The vein valves are necessary to keep blood flowing toward the heart, but they are also necessary to let blood to flow against the force of gravity. For example, blood that is returning to the heart from the foot has to be able to flow up the leg. Usually, the force of gravity would prevent that from happening. The vein valves, however, provide support for the blood as it climbs its way up the leg.

Unlike the arteries and veins, capillaries are very thin and fragile. The capillaries have only one protective cell wall. They are so thin that blood cells can only pass through them in single file. The exchange of oxygen and carbon dioxide also takes place through the thin capillary wall. The red blood cells inside the capillary release their oxygen, which passes through the wall and into the surrounding tissue. The tissue releases its waste products, like carbon dioxide, which passes through the wall and into the red blood cells.
Arteries and veins run parallel throughout the body with a web-like arrangement of capillaries, surrounded by tissue, connecting them. The arteries pass their oxygen-rich blood to the capillaries, which let the exchange of gases happen within the tissue. The capillaries then pass their waste-rich blood to the veins for transport back to the heart.
Capillaries are also involved in the body’s release of excess heat. During exercise, for example, your body and blood temperature rises. To help release this excess heat, the blood delivers the heat to the capillaries, which then quickly release it to the tissue. The result is that your skin takes on a blushing, red appearance. If you hold your hand under hot water, for example, your hand will quickly turn red for the same reason. Your arm, however, will most likely not change color because it is not feeling an increase in temperature.

Blood that flows up to the brain faces the same problem as the arm. If the blood is having a hard time climbing up to the brain, you will feel light-headed and possibly even faint. Fainting is your brain’s natural demand for more oxygen-rich blood. When you faint, your head comes down to the same level as your heart, making it easy for the blood to quickly reach the brain.
Because it lacks oxygen, the waste-rich blood that flows through the veins has a dark purplish color. Because the walls of the veins are rather thin, the waste-rich blood is visible through some parts of the skin as a purplish-blue color. If you look at your wrist, or hands, or ankles, you can probably see your veins carrying your blood back to your heart.
The Heart
The heart consists on four chambers, in which the blood fills after being pumped through the arteries, veins and capillaries. Two of the chambers, which form the curved top half of the heart, are called the atria; the other two, which form the bottom point, are called ventricles. You feel your heart beating strongest on the left side of your chest because the left ventricle is located there. This is the ventricle that contracts most forcefully.

The left side of the heart contains one atrium and one ventricle. The right side of the heart contains the others. A wall, called the septum, separates the right and left sides of the heart. A valve connects each atrium to the ventricle below it. The mitral valve connects the left atrium with the left ventricle. The tricuspid valve connects the right atrium with the right ventricle. The top of the heart connects to a few large blood vessels.
The largest of the blood vessels is the aorta, or main artery, which carries nutrient-rich blood away from the heart. Another important vessel is the pulmonary artery, which connects the heart with the lungs as part of the pulmonary system. The two largest veins that carry blood into the heart are the superior vena cava and the inferior vena cava. They are called “vena cava” because this means “heart’s veins.” The superior vena cava is located near the top of the heart; the inferior vena cava is located beneath this.

Cardiovascular Exercise
Cardiovascular exercise is performed mainly for physical health, weight management, and cardiorespiratory (hearth and lung) health. This kind of exercise requires large muscle movement over a continual period of time, which can elevate your heart rate to at least fifty percent of its maximum level. Some forms of this exercise are biking, swimming, jogging or walking.
There are numerous benefits that result from cardiovascular exercise. They include a decreased blood pressure, increased HDL (good) cholesterol, decreased LDL (bad) cholesterol, decreased body fat, decreased glucose-stimulated insulin secretion (this increases thickness of capillaries and blood flow to active muscles), increased heart and lung function and efficiency, and decreased anxiety, tension, and depression.

All of these benefits combine to help lower your risk of cardiovascular disease by reducing risk factors like obesity, hypertension, and high blood cholesterol. Also, cardiovascular exercise serves as a basis for the activities of daily living, sports, and other outdoor activities. Activities such as tennis, golf, skiing, dancing, basketball, hiking, and strength training programs all benefit from cardiovascular exercise. This will also cause you to have more stamina, less fatigue and less risk of injury when taking part in day-to-day as well as physical activities. However, there are several precautions you should take to help maximize exercise safety.