Lactate Threshold
Definition
Lactate threshold (LT) is the exercise intensity at which lactate begins to accumulate in the blood faster than it can be cleared. Above LT, the body cannot sustain effort indefinitely.
Why it matters
LT is the single most important predictor of endurance performance. Tempo runs and threshold intervals are designed to push LT higher — enabling faster sustainable paces at the same effort level.
How FlipMP uses it
FlipMP identifies your threshold zone from historical training data and heart rate trends. Training in Zone 4 (threshold) regularly and tracking pace improvements at equivalent HR over time shows LT progress.
Related terms
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