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5-zone training · karvonen method · max hr from age · runs locally
[
inputs
]
age
resting hr (bpm)
max hr (leave blank = 220 − age)
karvonen formula (heart rate reserve)
max hr:
190
bpm · hrr:
130
[
current hr (optional)
]
[
zones
]
z1
recovery
95–114 bpm
50–60%
active recovery · light warm-up
z2
fat burn
114–133 bpm
60–70%
aerobic base · sustainable effort
z3
aerobic
133–152 bpm
70–80%
improves cardiovascular fitness
z4
threshold
152–171 bpm
80–90%
lactate threshold · hard effort
z5
vo2 max
171–190 bpm
90–100%
maximum capacity · short intervals
[
status
]
>
ready