Ch-ch-ch-changes! Mathalicious is now Citizen Math . Please visit www.CitizenMath.com for the real-world math lessons you know and love. Alternatively, you can continue to access Mathalicious.com until the end of the school year, at which point Mathalicious will ride off into the sunset. For more details about the transition to Citizen Math, please click here.
How fast does your heart beat? What’s the fastest it could beat? And when you exercise, how hard should you be pushing your heart?

In this lesson, students write and graph an equation for a person’s maximum heart rate in terms of his or her age. Next, they learn about the effects that different heart rates have on the body and calculate ideal heart rate zones for different types of workouts. Do your students know how hard they have to work in order to burn fat? The answer may surprise them!

Students will

  • Write and graph a linear equation to model a person’s maximum heart rate
  • Calculate heart rates during exercise as a percentage of the maximum
  • Calculate and graph heart rate zones to target different types of exercise
  • Discuss limitations of the model for maximum heart rate

Before you begin

Students should be able to fluently work with percentages, including calculating the percent of a number. Although the linear functions involved in this lesson are relatively straightforward, some previous exposure to graphing and solving linear equations will also be helpful.

Common Core Standards

Content Standards
Mathematical Practices


Dr. Steven Gelani