Use the distance or average pace from a solo 30-minute time trial.
Your average HR during the last 20 minutes is your estimated LTHR (Lactate Threshold Heart Rate). This value alone produces Joe Friel's published running HR bands, including the open lowest and highest zones.
Threshold Pace
4:37
min/km
Speed
13.0
km/h
30min Distance
6.50
km
LTHR
—
bpm
| Zone | Pace (min/km) | % Threshold |
|---|---|---|
Zone 1 | Slower than 5:57 | Slower than 129% |
Zone 2 | 5:16 - 5:57 | 114-129% |
Zone 3 | 4:54 - 5:13 | 106-113% |
Zone 4 | 4:34 - 4:51 | 99-105% |
Zone 5a | 4:29 - 4:37 | 97-100% |
Zone 5b | 4:09 - 4:26 | 90-96% |
Zone 5c | Faster than 4:09 | Faster than 90% |