Lactate Thresholds - Definitions
What is the lactate threshold?
If you are looking for a simple definition of the lactate threshold that everybody agrees to, you will not find it here because there isn't one. People use different defintions and that is why it is confusing. We will use the following definition as the lactate threshold on this web site:
The curve below is a typical lactate curve. Several measurements have been
taken as well as a resting lactate. Notice that the lactate remains close to the resting rate for
several measurements even though the muscles are producing anaerobic energy, and producing lactate.The
lactate is not yet leaving the muscles and most is being consumed for aerobic metabolism in the
originating muscles. When the lactate starts to rise, this means some of the lactate being produced is
leaving the muscles and entering the bloodstream. It is often hard to pinpoint a specific place on the
curve where the rise really starts. We will ask a question of the reader:� where does the lactate curve
start to rise? The problem with getting an acceptable answer to this question has taken up a lot of the
time of many researchers.
On this website the lactate threshold is the maximal lactate steady state because it has physiological meaning that is based on lactate metabolism and is highly correlated with endurance performance. It is the definition that most coaches use as well as a lot of researchers. If you came here to find out what anaerobic threshold means, it too has more than one definition. See the popup for anaerobic threshold on the lactate threshold web page.