Which statement about the Karvonen target heart rate calculation is true?

• A. Target HR = HRmax × percentage
• B. Target HR = Resting HR + (percentage × HRR) where HRR = HRmax − HRrest.
• C. Target HR = 0.5 × (HRmax + HRrest)
• D. Target HR = Resting HR × percentage

Answer: (B)

The main idea is that the Karvonen method sets training intensity using heart rate reserve, which adjusts for both your resting heart rate and your maximum capacity. The target heart rate is calculated by adding a portion of the heart rate reserve to the resting heart rate. In formula form: Target HR = HRrest + (percentage × HRR), where HRR = HRmax − HRrest.

This means you’re not just chasing a percentage of your max, but you’re working off how much you can rise above your resting level. For example, if your maximum is 190 bpm and your resting is 60 bpm, your heart rate reserve is 130 bpm. At 60% intensity, your target would be 60 + 0.60 × 130 = 138 bpm.

The other expressions don’t capture that idea. Multiplying max heart rate by a percentage ignores resting rate and the available reserve. Using resting heart rate times a percentage misrepresents intensity because it doesn’t relate to how much you can actually increase above rest. The form 0.5 × (HRmax + HRrest) is mathematically equivalent to the Karvonen form only at a 50% intensity, not as a general rule.