Why Must The Heart Beat Faster During Exercise? - Sharecare

Advertisement Health TopicsFitnessTypes Of Exercise Why must the heart beat faster during exercise? National Academy of Sports Medicine When you exercise the muscles in your body must contract, in order to do that they need oxygen, glucose, a molecule called ATP, and amino acids. As your muscles use these compounds and contract themselves, they will create waste products like carbon dioxide, and lactic acid that must be carried away from the muscles. When exercising many muscles will all require nutrients and elimination of waste products constantly at the same time. To meet this demand the heart must rapidly increase the rate at which it beats and pushes blood through the body. This is why the heart beats significantly faster during exercise. Discovery Health

Your heart is a muscle, and gets a workout during exercise. Its job is to get more blood out to the body's muscles when they work hard.

When you are exercising, the heart's blood flow increases by around four or five times from when you are at rest. Your body does this for you by increasing the rate of your heartbeat, thus increasing the amount of blood that goes out to the rest of the body.

Cardiac output is the rate of blood pumped by the heart. You get that from multiplying the heart rate, the rate at which the heart beats, by the stroke volume, which is the volume of blood ejected by the heart with each beat. When you are at rest, the cardiac output is about 5 liters a minute. With exercise, sympathetic nerves stimulate the heart to beat faster and more forcefully; the heart rate can actually increase about threefold.

At the same time the veins constrict due to the sympathetic nerve stimulation. More blood being returned from the working muscles, along with the vein constriction, increases the venous return, or the amount of blood returned to the heart. This increased venous return increases the stroke volume by about 30 to 40 percent.

When the heart pumps at full force, the cardiac output can be about 20-25 liters per minute.

Show More

Continue Learning about Types Of Exercise

What are the three main types of exercise?What are the three main types of exercise? Learn more from our experts about the three main types of...More AnswersWhat are the components of a good exercise program?What are the components of a good exercise program? There are three components of exercise: stamina,...More AnswersHow do I perform a seated shoulder fly with both arms?How do I perform a seated shoulder fly with both arms? Sit on a bench and hold a dumbbell in each ha...More AnswersHow do I perform a single leg shoulder press with one arm?How do I perform a single leg shoulder press with one arm? Stand on one leg and hold a dumbbell at s...More Answers

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.

Types Of Exercise

Learn More

Trending on Sharecare

article

Triple-negative breast cancer: what to ask your oncologist

article

One-to-one: metastatic breast cancer

article

Is your stress harming your health?

article

Ask the experts: metastatic breast cancer risks and causesWhich age groups are the most stressed in America?

Those aged 18-33 years old ...

What's the fast track system at an emergency room (ER)?

Some ERs utilize a fast tra...

What are the differences between emergency room levels?

Emergency departments are c...

slideshow

8 things your breast cancer surgeon wishes you knew