What is lactate threshold?

Lactate threshold (LT) is the exercise intensity above which lactate accumulates in the blood faster than it can be cleared. It roughly corresponds to the pace you could sustain for about 60 minutes in a race. Training at and around LT is one of the most effective ways to improve distance running performance.

How accurate is this estimate?

Race-time based estimates are reasonably accurate for most runners. A 10K race result is the most reliable predictor of LT pace. The estimate assumes you ran a well-paced race at maximum effort. Laboratory testing provides the most precise measurement.

How do I improve my lactate threshold?

Tempo runs (20-40 minutes at LT pace), cruise intervals (repeated 5-10 minute efforts at LT pace with short recovery), and progressive long runs all improve LT. Consistency over 6-12 weeks produces measurable improvement.

VDOT is a measure of running fitness developed by Jack Daniels. It combines VO2max with running economy into a single value. Higher VDOT = fitter runner. VDOT is used to set training paces across all zones and predict equivalent race performances.

RunCalcs

Lactate Threshold Estimator

Estimate your lactate threshold from recent race times.

Recent Race Distance

Distance measurement

Race Time (minutes)

Time duration

Race Time (seconds)

Time duration

Resting Heart Rate

Rate value for this calculation

Max Heart Rate

Rate value for this calculation

Age

Your age in years

How We Calculate This

LT Estimation

Lactate threshold pace is estimated from race performance using the Daniels VDOT model. LT pace is approximately 5% slower than 10K race pace for most runners. LT heart rate is typically 85-90% of maximum heart rate.

Training Zones

Five training zones are derived from LT pace and heart rate, providing targets for recovery runs, easy runs, tempo work, threshold training and VO2max intervals.

Frequently Asked Questions

Related Calculators

VO2max Estimator

Estimate VO2max from Cooper test, Rockport walk, 1-mile run or race time with fitness categories and training zones.

Last updated: 2026-03-01

All calculations are estimates. Always consult a coach or medical professional for personalised training advice.