Training calculators
Estimate practical heart-rate, pace, and power bands from a lactate threshold field test or known threshold result.
Updated 2026-06-15
Lactate threshold calculator
Enter one tested threshold anchor to estimate practical training bands for heart rate, pace, or power.
Threshold source
Threshold HR
172 bpm
heart-rate anchor
Threshold pace
7:30 /mi
pace anchor
Threshold power
260 W
power anchor
Source
30-minute field test estimate
Threshold row
Use the LT row as the hard-steady anchor, then keep most endurance volume below it unless the session calls for threshold work.
Retest
Retest when race results, repeat workouts, or perceived effort stop matching the numbers.
Easy aerobic
Durable endurance
129-146 bpm | 8:51-10:08 /mi | 156-195 W
Steady
Controlled aerobic pressure
146-155 bpm | 8:06-8:51 /mi | 198-229 W
Tempo
Comfortably hard
155-163 bpm | 7:44-8:06 /mi | 229-244 W
Threshold
Hard steady anchor
163-172 bpm | 7:30-7:44 /mi | 247-260 W
Over threshold
Short-repeat pressure
172-181 bpm | 7:17-7:30 /mi | 263-273 W
How it works
Use this calculator when you have a threshold anchor from a 30-minute field test, lab test, coach assessment, race estimate, or device estimate. It converts that anchor into practical training bands for planning, not a replacement for direct blood lactate testing.
How to use it
- Choose whether the anchor came from a field test or from a known lab, coach, race, or device result.
- Enter at least one threshold anchor: heart rate, pace, or power.
- Use the threshold row as the hard-steady anchor, then adjust based on sport, terrain, heat, fatigue, and coach-tested zones.
Questions
Is this a real lactate test?
No. A true lactate test measures blood lactate across stages or constant-load efforts. This calculator turns an existing threshold estimate into usable training bands.
What field test should I use?
A common starting point is a steady 30-minute time trial and the final 20-minute average heart rate, pace, or power. Use a safer coached or lab protocol if you are unsure.
Can I enter only heart rate, pace, or power?
Yes. The calculator only shows bands for the anchors you enter, so you can use heart rate for running, power for cycling, or pace on repeatable flat routes.