Which expression represents the upper target heart rate zone (Upper THRZ) in the Karvonen method?

Which expression represents the upper target heart rate zone (Upper THRZ) in the Karvonen method?

• A. HRR × 0.6 + RHR
• B. HRR × 0.9 + RHR
• C. MHR + RHR
• D. HRR × 0.85 + RHR

Answer: (D)

In the Karvonen method, you find target heart rate by starting with resting heart rate and adding a portion of the heart rate reserve (HRR = MHR − RHR). The general form is Target HR = RHR + (HRR × intensity). For the upper target zone, the intensity is set high, commonly 0.85 (85%). So the upper zone is RHR + (HRR × 0.85). For example, if resting HR is 60 bpm and max HR is 190 bpm, HRR = 130. Upper THRZ ≈ 60 + 130 × 0.85 ≈ 171 bpm. The other expressions don’t fit the upper zone concept: using 0.6 targets a lower intensity, not the high end; adding MHR to RHR isn’t how Karvonen builds the target (the formula already centers around HRR, not directly on MHR); using 0.9 would push toward a higher end than the standard upper boundary in many practice contexts, whereas 0.85 is the typical upper threshold used.

In the Karvonen method, you find target heart rate by starting with resting heart rate and adding a portion of the heart rate reserve (HRR = MHR − RHR). The general form is Target HR = RHR + (HRR × intensity). For the upper target zone, the intensity is set high, commonly 0.85 (85%). So the upper zone is RHR + (HRR × 0.85).

For example, if resting HR is 60 bpm and max HR is 190 bpm, HRR = 130. Upper THRZ ≈ 60 + 130 × 0.85 ≈ 171 bpm.

The other expressions don’t fit the upper zone concept: using 0.6 targets a lower intensity, not the high end; adding MHR to RHR isn’t how Karvonen builds the target (the formula already centers around HRR, not directly on MHR); using 0.9 would push toward a higher end than the standard upper boundary in many practice contexts, whereas 0.85 is the typical upper threshold used.