Aerobic Threshold
The aerobic threshold (AeT) is sometimes defined as the exercise intensity at which anaerobic energy pathways start to operate and where blood lactate reaches a concentration of 2 mmol/litre (at rest it is around 1). This tends to be at a heart rate of approximately 20-40 bpm less than the anaerobic threshold and correlates with about 65% of the maximum heart rate. The anaerobic energy system does not utilize oxygen to create Adenosine triphosphate (ATP) and uses glycogen/glucose. Lactic acid is the by-product of creating ATP for working muscles.
Read more about this topic: Lactate Threshold
Famous quotes containing the word threshold:
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—Mark Twain [Samuel Langhorne Clemens] (1835–1910)