The contemporary role of lactate in exercise physiology and exercise prescription - a review of the literature.

Lactate is a key molecule in exercise metabolism. In the last two decades, there has been a revolution in the understanding of its role - from a byproduct of hypoxic muscles to a major energy resource and a signaling molecule - 'lactormone'. The aim of this review is to compile all the up-to-date information that is available on the general metabolism of lactate, but also the specific use that exercise physiologists, coaches, and athletes can get out of lactate measurements, lactate-based training zones, and periodization of training sessions. Since the revolution in the understanding of lactate's role in normal metabolism and disease in the late 20th century, more evidence has been assembled regarding the specific part it plays in exercise. From the vast body of knowledge, the researchers developed the concept of training intensity distribution into zones according to the level of blood lactate. The end goal of training to a specific lactate level or 'threshold' is the increased adaptation to specific training stimuli and ultimately better performance, which has been backed up by the achievements of numerous athletes training according to this concept.