All Pumped Up

Each beat of your heart pumps blood through your body. That blood is packed with oxygen. When you exercise, your body needs more of this oxygen-rich blood to keep going. So when you’re active, your heart really gets pumping.

How does exercise affect your heartbeat?

You can find out by doing this easy experiment. You may want to work with a partner.

    Make a Prediction

  • • Exercise will make my heart beat faster.

    Gather Your Materials

  • • watch or other timepiece that has a second hand

  • • notebook paper; pencil

CONDUCT YOUR INVESTIGATION

Use the following steps to help determine if your prediction is correct.

  • 1 Place two fingers on your wrist. Find a spot where you feel a thump. That’s your pulse. Each thump represents a heartbeat.

  • 2 Count how many thumps you feel in thirty seconds. Write down the number.

  • 3 Now run in place as fast as you can for two minutes.

  • 4 As soon as you finish, count your pulse again. How many thumps do you feel in thirty seconds now?

    Conclusions

  • • Did your heart beat more or less after you exercised?

  • • Why did your heartbeat change when you exercised?

Photograph of a teenage girl using small hand barbells
In Other Words

  • really gets pumping works very hard

  • thump beat

  • in place without moving forward

Before You Move On

  • 1. Conclusions What other kinds of activities can make your heart beat fast or slow?

  • 2. Explain How does this experiment help you better understand the article?