If endurance is a critical component of your overall fitness then listen close. You NEED to know what lactate threshold training is. Why you ask? Well to put it as simply as possible, your lactate threshold determines how long and how hard you can exert near maximum effort, or to use the true term, exert yourself at your anaerobic threshold. So what I am saying is this; that wall you hit when you are running, that tries to bring you down to your knees and crumple in pain, is your lactate threshold. Now that we know our enemy, let’s learn how to beat it down.
First we need to understand some key concepts and know that the following is a simplification of a much more complicated set of biochemical processes but will suffice for our purposes.
So to begin, we should dispel a long circulated myth that while running we are not producing lactate at all and that the burn we feel well into the run happens because of a sudden onset of its production. This is wholly untrue. The hydrolysis of ATP, our body’s main source of energy, within our muscle’s causes a steady accumulation of hydrogen protons H+ within our muscle’s capillaries. Lactate production is actually our bodies response to this acidification by the hydrolysis of ATP thus reducing the burn.
There is a point though when our body begins to produce lactate at rates that are too fast for our bodies to metabolize, and this is the lactate threshold. To demonstrate, try sprinting a 400. At some point, unless you are a seasoned athlete, your legs are going to want to stop moving and it will happen very quickly. Rest for a few minutes and you will be able to repeat the exercise likely sprinting the same distance or slightly shorter. Each time your legs want to stop, you have experienced your anaerobic threshold which is the anaerobic expression of your lactate threshold.
For distance runners, since you are employing aerobic energy pathways which are far more efficient than anaerobic pathways, which produce about 1/18 the amount of energy, you experience, at some point, an onset of blood lactate accumulation. Prior to this you were at your maximal lactate steady state which is basically the exercise intensity at which, as you might have guessed, lactate production is equal to lactate metabolization. Many researchers say that this measure is definitively one of the best indicators of athletic performance out there. That is how important it is.
So how does one increase their ability to effectively clear lactate at the rate it is being produced? There are several training regimens that can be employed. The first can be ignored if you are a seasoned athlete already but it is increasing the volume of your training. Say you do 90 minutes of cardio a week currently. Your goal should be to double that to 180 minutes over the time span of four weeks, gradually increasing the overall time each week. This helps to pump up our bodies capacity for mitochondrial respiration.
Another method, and one that I personally love, is interval training above your lactate threshold. So using the sprint 400m example. Say you could only sprint 200m of the 400m. Well a good interval then would be to sprint for 100m then jog 100m back to your starting point and rest 45 seconds. Repeat this 8-12 times. Do this 2-3 times a week increasing the distance every week as you feel yourself being able to complete the routine with greater ease. One particular variation that I enjoy is what some call corner-burns, which essentially is sprinting the curves of a 400m oval and jogging the straights, taking a one minute break after each lap and repeating that 5-6 times.
You can also do things like run at 95% of your max intensity for one minute then jog for two, then speed up to a sprint again for another minute for a total of 10-15 minutes depending on how much you can handle. The general idea is to exceed your lactate threshold then slow down and let your body recover, then speed up again and over time this trains your threshold.
If you train hard enough, your LT could be as high as 95% of your VO2 max, which is the max capacity of your body to utilize oxygen, though levels this high are generally reserved for elite athletes. A discussion of VO2 max and vVO2 max will come later.
I am just saying it’s possible and if you have the will to push, you will beat the wall down.
Check out this awesome infographic of our bodies metabolic pathways!