LACTATE ZONE CALCULATOR LT1 · LT2 · TRAINING ZONES

Build your curve. Know your zones. Train on target.

Enter HR + mmol/L steps Auto-estimates LT1 (2.0) & LT2 (4.0) Print / screenshot results

How to use: add your stage data (heart rate + lactate mmol/L). Hit Calculate. This page will estimate LT1 and LT2 by linear interpolation and generate simple training zones (below LT1, between LT1–LT2, above LT2).

UNLEASH THE BEAST

Stage Data

Heart Rate (bpm)	Lactate (mmol/L)	Action

Tip: enter at least 5–7 stages (more is better). Keep HR increasing each stage.

Lactate Curve

Add data and hit Calculate.

Results

LT1 Estimate

— bpm @ 2.0 mmol

LT2 Estimate

— bpm @ 4.0 mmol

Training Zones

Zone	Range (bpm)	Use
Calculate to generate zones.

Note: zones here are lactate-anchor zones (simple and clean). If you want a full 5–7 zone model (and pace/power), we can build it off your full test protocol and goals.