Max heart rate
174bpm
Tanaka
220 − age
172bpm
classic
Zone 2
105–122bpm
aerobic base
Vigorous from
134bpm
about 77% of max
Show the math
Max HR = 208 − 0.7 × 48 = 174 bpm
Heart rate zones at 48
| Zone | BPM | % of max | Feels like |
|---|---|---|---|
| Zone 1 · Recovery | 87–105 | 50–60% | Easy, conversational |
| Zone 2 · Aerobic base | 105–122 | 60–70% | Steady, can still talk |
| Zone 3 · Tempo | 122–140 | 70–80% | Comfortably hard |
| Zone 4 · Threshold | 140–157 | 80–90% | Hard, short phrases |
| Zone 5 · Max effort | 157–174 | 90–100% | All-out, seconds to minutes |
Karvonen zones by resting heart rate
| Resting HR | Zone 1 | Zone 2 | Zone 3 | Zone 4 |
|---|---|---|---|---|
| Resting 55 | 115–127 | 127–139 | 139–151 | 151–162 |
| Resting 65 | 120–131 | 131–142 | 142–153 | 153–163 |
| Resting 75 | 125–135 | 135–145 | 145–155 | 155–164 |
Karvonen: resting + (max − resting) × intensity. More personal if you know your resting rate.
How to use it
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These are estimates, not a diagnosis. A clinician can account for your health history and medicines.
Other ages
Common questions
What is a good heart rate zone for a 48-year-old?
Zone 2, about 105 to 122 bpm, builds aerobic base. Moderate exercise sits around 112 to 133 bpm.
What is the max heart rate at 48?
About 174 bpm by the Tanaka formula, or 172 by 220 minus age. Individual max can differ by 10 or more beats.