What Is Lactate Threshold And How Can You Measure And Increase It?

In last week’s post, I interviewed Rusty Moore about his newly released cardio/fat loss workout. While he gave some very eye-opening replies about Visual Impact Cardio, there was definitely one answer that stood out most … except for the one about beer :)

In the seventh question I had for Rusty I asked him to give Fitness Black and White readers one special  “golden nugget” that he found when creating his new course. That answer was based around training just below one’s lactate threshold.

Lactate Threshold Training

I think this guy may have been training above his lactate threshold for too long. Remember: too much of a good thing is too much. Don’t burn out!

If you haven’t read the entire interview about Visual Impact Cardio yet, I encourage you to do so. There are a few gems that you can pick out and apply to your cardio workout whether you decide to get one of his courses or not. In short though, here is part of Moore’s “golden nugget” answer:

“The intensity level that you can burn calories at for an extended period of time is just below lactate threshold. To get lean quickly, you will want to spend more time near your lactate threshold level.”

Okay, now that you know you need to spend more time training just below lactate threshold … what is lactate threshold? Rusty did provide a good formula for figuring that out but I also wanted to dive a little deeper into what lactate threshold is and how you should train with it in mind.

What Is Lactate Threshold?

First of all, we need to identify exactly what lactate threshold is and what this means to us. Not that Wikipedia is the absolute source for all definitions, but I do find their definition of lactate threshold as good and to the point:

“The lactate threshold (LT) is the exercise intensity at which lactate (more specifically, lactic acid) starts to accumulate in the blood stream … This happens when lactate is produced faster than it can be removed (metabolized) … When exercising below the LT intensity any lactate produced by the muscles is removed by the body without it building up.”

So if you are to workout out just below your lactate threshold that means that your body would be able to remove the lactic acid without it building up.

In short, your lactate threshold is the level of intensity that YOUR body begins to build up (and not metabolize) lactate acid. This is the point when your body burns the maximum amount of calories.

One bit of warning: your body will burn out if you consistently train at or above your lactate threshold. The good news: your lactate threshold increases as you become more fit. The higher your LT, the more fat you can burn and the harder you can workout without overtraining.

How to Increase Lactate Threshold

Ultimately, this can be done in a couple ways. For starters, trying doing either one of these two cardio workouts twice per week:

Option #1: Interval Lactate Threshold Training
Perform LT intervals at 90% and 105% of your lactate threshold. Do these for 20 minutes.

  • Warm up for 5 minutes
  • 3 minutes @ 105% of your lactate threshold
  • 1 minute @ 90% of your lactate threshold
  • Repeat intervals 4 times

Your total time will be 25 minutes. 5 minutes to warm up and 5, 4 minute sets of intervals.

Option #2: Continuous Lactate Threshold Training
Perform 20-30 minutes of steady state cardio at 95-105% of your lactate threshold.

How To Measure Lactate Threshold

Here is how Rusty Moore recommended finding your lactate threshold:

  • Exercise at a moderate pace for the first 5 minutes.
  • Gradually increase the speed until it feels somewhat challenging.
  • Maintain this speed for 20 minutes.
  • At the 15-20 minute mark check your heart rate.
  • Heart rate should be 165-180BPM (men) or 175-185BPM (women).

*If you could barely finish the 20 minutes then you were pushing a little too hard and you were performing above your LT. If your heart rate is below the above numbers, you were not pushing hard enough.

While running this test you will want to pay attention to the degree of incline (if any) as well as the speed, RPM and/or resistance level of the machine you’re on. All of these factors play a part in determining the intensity level and these all need to be monitored in order to get a true reading.

If you plan on using different cardio machines then you need to know your lactate threshold for each machine.

Once you know where your lactate threshold is at you can then do much of your cardio based on the advice that Rusty gave and train just below your LT most of the time.