lactate threshold


The level above which pyruvate—an intermediate product of anaerobic metabolism—is produced faster than it can be used aerobically; unused pyruvate splits into lactate (lactic acid) and positively charged hydrogen ions; continued exercise above the lactate, or anaerobic, threshold results in accumulation of these ions—acidosis—causing exhaustion and intramuscular pain

lac·tate thresh·old

(lak'tāt thresh'ōld) The workload during exercise of increasing intensity, when a measurable increase in venous blood lactate levels occurs in conjunction with an exponential increase in respiratory frequency.
See also: ventilatory threshold, anaerobic threshold
Synonym(s): onset of blood lactate accumulation.