Yesterday, I mentioned that i made a tweak to my Heart Rate Zones on my Samsung Health app. I switched to Heart Rate reserve option. Previously, it was Based on Max HR.
Based on Samsung Health, Heart Rate Reserve is the difference between your resting heart rate and your maximum heart rate. Heart rate reserve is an indicator of fitness and how hard you're working during exercise.
I asked ChatGPT on which is better to measure Heart Rate Zones, here's the answer:
For the most
accurate heart rate zone settings for running—especially if your goal is
improving performance, endurance, or fat burn—you should
base your zones on Heart Rate Reserve (HRR), which uses both:
- Resting Heart Rate (RHR)
- Maximum Heart Rate (Max HR)
This method is known as the
Karvonen Formula, and it's
more personalized than just using a percentage of Max HR alone.
Why Heart Rate Reserve (HRR) is More Accurate:
- Takes your fitness level into account
A lower resting HR generally means you're fitter. HRR reflects this, while Max HR-only methods don't.
- Improves zone precision
Two people with the same Max HR but different resting HRs will have different cardiovascular responses, which HRR captures.
Karvonen Formula (HRR-based Zones):
\text{Target HR} = ((\text{Max HR} - \text{Resting HR}) \times \% \text{Intensity}) + \text{Resting HR}
Example (plug in your actual numbers):
- Max HR: 190 bpm
- Resting HR: 60 bpm
Zone 2 (60–70% HRR):
((190 - 60) \times 0.60) + 60 = 138 bpm
((190 - 60) \times 0.70) + 60 = 147 bpm
\Rightarrow Zone 2 = 138 to 147 bpm
How to Set This in Your Watch:
Most advanced fitness watches (Samsung, Garmin, Polar) let you:
- Manually input Resting HR and Max HR, or
- Choose “Heart Rate Reserve” as the basis for zones
Make sure to:
- Set your Resting HR from your true resting state (e.g. right after waking up)
- Estimate Max HR from testing (or use 220-age as a rough estimate if unsure)
- Select “Heart Rate Reserve” if your device supports it
Summary:
| Method | Uses RHR? | More Accurate? | Recommended? |
|---|
| % of Max HR only |  |  | No |
| Heart Rate Reserve |  |  | Yes! |