Here’s How Hard Your Heart Actually Works


February 2, 2023

February is American Heart Month, which means it’s time to show some love to one of your most vital organs. While you depend on your heart every day, this month provides opportunities to give it some extra attention. As you do, you’ll discover what an incredible organ it really is.

5 Reasons You Need Your Heart

You know that you can’t live without your heart. It pumps essential blood throughout your body. But to fully appreciate your heart and all it does, take a look at how this organ functions.

#1) The heart takes care of at least 1.2 gallons of blood.

The average human adult has between 1.2 and 1.5 gallons of blood in the body. When you step on the scale, your blood is responsible for nearly 10% of the number you see.

That’s a lot of blood to move around, but your heart gets the job done. It sends that full volume throughout the body and back to the heart in less than a minute.

It’s hard to imagine walking across the full length of the U.S. That’s about a 12,000-mile trip from coast to coast. Yet every day, the blood in your body travels four times that distance. It’s all because of the hard work of your heart.

#2)  It sends blood to pick up oxygen.

When blood enters the right side of your heart, it’s low on oxygen. That’s because the blood has just delivered the oxygen to the various parts of the body and now needs refueling.

The right side of your heart consists of two chambers. Blood first enters the right atrium. From there, it flows into the right ventricle. That ventricle pumps the blood toward your lungs.

In the lungs, the blood can acquire a fresh supply of oxygen.

#3) It delivers oxygenated blood to the body.

Oxygenated blood doesn’t immediately flow to all the parts of your body. Instead, it returns to the heart. But this time, it enters on the left side.

As on the right, the left side has an atrium and a ventricle. The blood goes into the atrium and is then delivered to the ventricle.

The ventricle sends the blood into the aorta. From there, it travels throughout the body on its life-sustaining mission.

Once it’s completed its trip, it returns to the right atrium to restart the cycle.

#4) Its valves keep blood flowing in the correct direction.

Between each section of the heart, there’s a valve. Two of the valves separate the atria from the ventricles. The other two separate the ventricles from the blood vessels leaving the heart.

The valves are essential because they control the flow of blood. Without them, your blood might try to flow backward through the system. Because of the heart’s valves, blood can move in the forward direction.

#5) The heart listens to electrical signals.

The heart is a muscle. It moves blood through the chambers and into the body by contracting and relaxing again and again. Electrical signals make this process happen.

The right atrium of your heart contains a built-in pacemaker. It’s called the sinoatrial (SA) node. When it gives off an electrical impulse, both atria contract.

The ventricles need to contract, too, but not at the exact same time as the atria. A second node, the atrioventricular (AV) node, puts the electrical impulse on a delay before it gets to the ventricles. As a result, they contract as the atria relax.

How Hard Your Heart Works

You don’t typically feel your heart working as hard as it does, but it’s putting forth a tremendous amount of effort every day.

To demonstrate this for yourself, hold a tennis ball in your hand. Close your fingers and squeeze the ball as hard as you possibly can. That’s the amount of strength that goes into pushing your blood from your heart into your blood vessels.

Imagine sprinting at top speed down a racetrack. Think about how hard your leg muscles would be working. But those tired legs have nothing on your heart. It exerts more effort than that even when you’re at rest.

When you’re relaxing, it’s normal for your heart to beat at least 50 times a minute. Some people’s resting heart rate is closer to 100 beats per minute. When you’re hard at work — exercising, for example — that number goes even higher. You can expect your heart to beat about 100,000 times every single day.

As you sleep, your heart rate slows down a bit. Still, the heart never stops. All day and night, it keeps pumping to give your body the nourishing blood that it needs for survival.

Fun Facts About the Heart

You might think that the sound of your heart beating is made by your muscles contracting and releasing. It’s actually produced by the valves. You’re listening as they open and close.

Another common misconception about the heart is where it’s located. It’s probably much closer to the center of your chest than you realize. Sure, its spot is a bit more to the left than the right, but it’s probably not as far over as you’ve been imagining.

You know that your heart is a muscle, but that’s not all there is to it. This organ is composed of three layers. The muscular part is the middle layer: the myocardium. On the inside, there’s a layer of lining called the endocardium. There’s also an outer layer for protection. It’s known as the epicardium.

On average, an adult heart weighs around 10 ounces. And it’s approximately the same size as two fists placed together.

That little organ is a powerhouse of never-ending strength. Its 100,000 daily beats add up to 35 million beats in a year. That comes to nearly 3 billion heartbeats during an average human lifespan.

And those billions of heartbeats can pump a remarkably large amount of blood. About 2,000 gallons’ worth of blood moves through the heart daily. For reference, 2,000 gallons of water would fill an 80-square-foot swimming pool.

If you live an average lifespan, your heart will have moved almost 1.5 million barrels of blood by the time you die. To put that in perspective, imagine you wanted to move that much liquid by train. It would take close to 200 railroad tank cars to carry it all.

All in all, the heart is a pretty remarkable organ. Even when you’re paying it no mind, it works hard for you every minute of every day. That’s why it’s so critical to pay attention to your heart health, to make the most of this critical organ. You can support your cardiovascular system with frequent exercise, a well-balanced diet and regular medical care – including physical and mental health.