The Lactate Threshold...the most important piece of training information

Lactate Threshold. What, you ask, is that? I'm sure you've heard of lactic acid and could probably say you're anti-acid (of the lactic variety). It makes your muscles burn, right? Wrong. Let's have a simple lesson in sports science...

When you exercise, your respiratory system, cardiovascular system, and muscles all respond to the intensity, whether easy or hard. A lower intensity is obviously easier, due to the fact that your cardiovascular system can consume and utilize enough oxygen to meet the demands of the muscles. This is termed aerobic, or utilizing oxygen. As intensity increases, your cardio system will have a harder time getting enough oxygen to the working muscles, depending on how fit you are. Soon, if the intensity is hard enough, your body will be running strictly on the fuel that is already sitting in the muscle, since the cardiovascular system can't match the oxygen demands of the muscles. This is referred to as anaerobic (or without oxygen). OXYGEN is key.

At any given moment, even just sitting on your duff, your body produces lactate. It is a chemical byproduct of metabolism. Lactate is not the bad guy. When oxygen is present (as we learned above, at lower intensities when your cardiovascular system is matching the demands of the muscles), lactate can actually be turned into energy. Oxygen helps to remove it from the blood so it can then be used as fuel. So it's actually the good guy! The problem happens when you start working at a harder intensity (pushing into an anaerobic state, or "not enough oxygen"). Because there is a lack of sufficient oxygen, lactate will start to build up in the blood. As it builds up, it has to be "deconstructed", so to speak, and ends up releasing Hydrogen ions in the process. The hydrogen ions put the muscles in a slightly acidic state causing them to "burn". Blame the Hydrogen ions, not the lactate!

So what? (Right about now you're hating science and just want to train.) With training, we can delay the process: meaning, we can cause lactate to start accumulating at a harder intensity. When lactate begins to accumulate in the blood begins of a lack of oxygen sufficiently removing it, we refer to this as the LACTATE THRESHOLD. When you hit your lactate threshold as you train, the lactate is beginning to accumulate and soon you will be exhausted if you go much harder. By knowing when your lactate threshold occurs for you, you can pinpoint exactly at which intensity to train in order to improve the threshold. Why improve the lactate threshold? Because you will be able to go longer at a harder intensity than before. How do you improve the lactate threshold? You figure out at what intensity it occurs for you (and determine a corresponding heart rate), then train hovering around that heart rate for either cruise intervals (4-10 minute long bouts at your threshold with 1/4 the length of rest in between) or long, steady periods of time (15-30 minutes at threshold pace).

I will go out on a limb to say knowing your lactate threshold is more important than knowing your maximum heart rate with the corresponding heart rate zones and even more important than knowing VO2max. Who cares what your maximum values are when you can only perform for a steady state at just 50% of it?! Between two people with the same maximum values, the one with the higher lactate threshold will beat the other one every time.

So, stop training dumb by using the heart rate chart on the gym wall! Train smart knowing your lactate threshold!