Last updated: 3 October 2026
Reviewed by Jordan Morley, FA Level 2 Football Coach
The lactate threshold (LT) marks the intensity where lactate production exceeds clearance — causing a rapid rise in blood lactate and the onset of muscle fatigue. Training below LT develops aerobic capacity sustainably; training above it is limited to minutes. For most trained runners, LT is at approximately 80-90% of VO2 max and corresponds to roughly 10K race pace. Threshold training (tempo runs at LT pace) is the most effective single session type for improving 10K and half marathon performance.
- Lactate accumulates faster than cleared
- ~80-90% VO2 max for trained runners
- Corresponds roughly to 10K race pace
- Tempo runs at LT are highly effective
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Lactate threshold marks the exercise intensity where lactate begins accumulating in the blood faster than the body can clear it — training just below and occasionally at this threshold is central to most endurance programmes, since raising the pace or power at which this threshold occurs is one of the clearest, most trainable predictors of improved race performance.
FAQ
How is lactate threshold measured?
Direct measurement requires blood lactate sampling during a graded exercise test in a lab, though field tests (like a 30-minute time trial) and heart rate or pace estimates are commonly used as practical substitutes.
Why does raising lactate threshold improve performance?
A higher threshold means an athlete can sustain a faster pace or higher power output before lactate accumulates and forces a slowdown, directly translating to faster sustainable race paces.