Running Speed Zones (Z1-Z5)
Compute the five training-pace zones (recovery to VO₂max) from your lactate-threshold pace.
Result
Zone 4 (Threshold)
4:30/km
Threshold zone equals your LT pace.
- Z1 — RecoveryEasy conversational pace; for warm-ups and recovery runs.5:51/km
- Z2 — EnduranceAerobic base — most weekly volume happens here.5:11/km
- Z3 — TempoComfortably hard, just below LT (marathon pace).4:46/km
- Z4 — ThresholdAt LT — cruise intervals and threshold workouts.4:30/km
- Z5 — VO₂maxFaster than LT — 3-5 min interval reps.4:08/km
Step-by-step
- LT pace = 4:30/km.
- Each zone is a multiple of LT pace seconds. Slower zones use multiplier > 1; faster zones < 1.
- Example Z2 endurance: 4:30 × 1.15 = 5:11/km.
How to use this calculator
- Enter your lactate-threshold pace (use a recent 10K or HMP-equivalent if you don't know LT).
- Read the five zone target paces.
About this calculator
A simple Joe-Friel-style 5-zone pace model anchored on lactate threshold (LT) pace — your maximum sustainable pace for around an hour of all-out racing. The multipliers (1.30 / 1.15 / 1.06 / 1.00 / 0.92) define easy through VO₂max ranges. For heart-rate-based zones use the karvonen-heart-rate-zones calculator.
Frequently asked
A 30-min all-out run after warm-up — average pace from minute 11 to minute 30 is approximately LT pace. Or use a recent 10K (LT ≈ 10K pace minus 5-15 sec/km).
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