As athletes when we think of lactate we've come to believe it's something of a waste product that causes our muscles sizzle from pushing our limits. But the reality is that lactate has a number of essential purposes. The liver actually recycles it, and releases it as glucose. During intensive exercise it provides another source of glucose. It's almost like a survival mechanism developed from our evolution to help us extend our endurance or time to total exhaustion. There's also a misconception that you’re not making lactate until you reach your lactate threshold. Not true, you’re producing lactate around the clock just at a much lower level at lower heart rates. Our bodies clear lactate very efficiently and use it rapidly until we approach a very high level of muscular stress. To determine where your threshold is a blood sample is taken and when blood concentrations are around 4 mmol/L that’s normally considered your threshold.