The human heart has four distinct components: the left atrium, the left ventricle, the right atrium, and the right ventricle. The right side of your heart receives blood from the body and pumps it to the lungs. The left side of the heart does the exact opposite; it receives blood from the lungs and pumps it out to the body.
Before every heartbeat, the heart fills with blood and its muscle contracts to squeeze out the blood with enough pressure to push it through the arteries. Your heart is about the size of your fist, so you can try making a loose fist and then squeezing as hard as possible - that’s how your heart beats inside your chest!
The Importance of a Healthy Heart
Many different factors affect your heart’s health, that’s why it’s so necessary to adopt a healthy lifestyle! If your heart isn’t healthy, there is a good chance that your other organs are unhealthy as well.
The greatest risk factor for heart disease is directly related to a person’s activity level. Living a sedentary lifestyle (spending more time sitting or lying down than being active) almost doubles your risk of heart disease or failure.
A person’s heartbeat can reveal a lot about their cardiovascular fitness, which is extremely important to good health. When a person is in good cardiovascular condition (that is, their heart and lungs are in good condition), the volume of blood their heart is able to pump with each beat increases, and so does the amount of blood in their body. Every time their heart beats, more blood is carried to their muscles, bringing oxygen and nutrients and carrying away waste more efficiently. This means that their heart will have to beat more slowly when they are at rest, and that it will return to resting rate more quickly after exercise, because they can supply their bodies with oxygen and nutrients (and get it to return to normal) with fewer beats per minute.
Think of a person’s body as a city, and their cardiovascular system as the streets and highways carrying people around to all the organs and tissues. If a person is in good cardiovascular condition, their city streets and highways are wider and well maintained, and so more cars can get where they need to go faster. If they are in poor cardiovascular condition however, the streets and highways are narrow, and can carry fewer cars at one time.
One of the ways a doctor checks heart health is by listening to a patient’s chest using a stethoscope. A stethoscope is made of solid, yet flexible, materials that transmit the sound of a heartbeat more efficiently than trying to put their ear to a patient’s chest. This way is much less invasive! When listening to a patient’s heart, they are checking for the normal ‘lub-dub’ sound it makes as it contracts to pump blood. Any irregular patterns or sounds (like a ‘whoosh’) might indicate a problem that should be investigated.
Make a Simple Stethoscope at Home!
If you want to be able to listen to your heartbeat without going to the doctor, it’s relatively easy to make a stethoscope at home that will help you hear what’s going on inside your chest. Here’s what you’ll need:
You can use this stethoscope to measure your fitness level by counting the number of times your heart beats in a minute. First, measure your standing heart rate by standing upright for 2 minutes. Be sure to stay still! With your new stethoscope, listen carefully to your heartbeat. Count the number of times you feel your heartbeat in 15 seconds.
Using your watch or stopwatch, time this precisely and write down the number of beats you hear. Multiply this number by four to get the number of beats per minute! Find the number of beats per minute in the table below, and record how many points you earned. Be sure to write this down!
Start by jogging in place for 10 seconds and time this with your watch or stopwatch. As soon as you stop, immediately begin recording how many times you feel your heartbeat in 15 seconds and write this number down.
Continue recording how many times your heart beats every 15 seconds until the number is the same as when you took your standing heart rate. Write each number down. Now, count how many numbers you had to write down, and divide that number by four. This is how many minutes it took for your heart rate to return to the normal standing rate.
Multiply the first number you wrote down immediately after exercise by 4 to get beats per minute. Make sure to write this down too! Find the number of minutes it took for your heart rate to return to normal in the third table below, and record how many points you earned. Be sure to write this down! If it took longer than 2 minutes, give yourself 6 points.
“Your Heart and Blood Vessels”. Cleveland Clinic Health Library. Accessed on 6/1/17.
Hudson, Dawn. “Re-Digitized Human Heart”. Released into the public domain. Uploaded on 6/2/17 from publicdomainpictures.net
Capac, Manco. “Atrial Septal Defect”. Released into the public domain. Uploaded on 6/2/17 from commons.wikimedia.org
Oberholster, Venita. “Healthy Diet Educational Poster”. Released into the public domain. Uploaded on 6/2/17 from publicdomainpictures.net
Nyren, Erin (2014). “Cardiovascular Fitness, Explained With Cars”. Science Projects for Grades 7 and 8. Discovery Express Kids, LLC, Fargo, ND.
Hodan, George. “Stethoscope”. Released into the public domain. Uploaded on 6/2/17 from publicdomainpictures.net