When I began thinking about writing this week’s post, I decided I wanted to begin discussing factors that could affect how fast you run, and how you can address these to help you achieve your running goals for 2017. There was one specific factor that I was going to discuss, however, I read an article during the week that inspired me to write about another factor that can not only affect your running speed, but may also reduce your risk for cancer.
There are several factors that affect your running speed. Some of them are genetically determined and so, you can’t change them that much. However, there are other factors that you can affect and one of them is your lactate threshold, or more specifically, the speed at which your lactate threshold occurs.
What is Lactate Threshold and Why Is It Important?
Basically, lactate threshold is the point at which your body is producing lactic acid at a rate faster than the rate at which your body is removing it. Thus, your body will significantly accumulate lactic acid and this will affect your muscle contraction and energy production, thus limiting your running performance. Depending on the fitness level of the individual, lactate threshold pace may be a pace at which a runner would run a 10k or a half marathon.
Another way to think of lactate threshold is the following:
Let’s say you had one of those Dixie cups and poked a few holes in it. Then you started pouring water in the cup. If you don’t pour the water in too quickly the cup won’t fill up and overflow because it is draining through the holes you poked in it. Now, let’s say you pour water into the cup at a faster rate, faster than the rate in which it is draining out of the holes you poked in it. Well, the cup will fill up and then begin to overflow.
This is similar to what can happen when you are running. If you are running at a slow enough pace, your body will be able to remove the lactic acid you are producing while you run. But, if you increase your pace too quickly, it won’t be able to handle the increased lactic acid production and you will either have to slow down or stop completely.
The speed at, or just below lactate threshold is the fastest pace that you will be able to maintain for a sustained period of time. If you increase your pace above your lactate threshold, you won’t be able to maintain that pace for more than a few minutes. Thus, if you can increase the pace at which your lactate threshold occurs, you should be able to complete your race in a faster time. That is why lactate threshold is considered one of the most important factors affecting race performance.
Lactic acid produced in the body will be converted to lactate and hydrogen ions. Hydrogen ions can increase the acidity in the body and impact different functions in the body such as muscle contraction. Lactate can actually be used as an energy source by certain organs in the body such as the heart.
How Do I Determine My Lactate Threshold?
The most accurate way to determine your lactate threshold is to have it assessed in a lab while you are running. As your speed is increased, blood samples are taken and your blood lactate levels can then be measured. Your lactate threshold is the speed in which either one of two things occur: one, you reach a specified blood lactate concentration (usually 4.0 mmol/L of blood), or two, there is a point in which there is sudden rapid increase in your blood lactate concentration.
However, this is invasive and can be costly, and labs that do this type of testing may not be available near you.
So, what can you do instead?
We can estimate our lactate threshold pace by running by feel. If fact, I highly recommend training by feel for most of your training runs. I recommended using the rating of perceived exertion scale (RPE) developed by Borg.
Borg Rating of Perceived Exertion (RPE) Scale:
6 – No exertion at all
7 – Extremely light
9 – Very light
11 – Light
13 – Somewhat hard
15 – Hard
17 – Very hard
19 – Extremely hard
20 – Maximal exertion
Depending on your level of fitness, your lactate threshold will likely occur at a pace in which the effort feels somewhat hard to hard, or an RPE of 13-15. For those who are untrained, lactate threshold may occur between an RPE of 11-13.
How Can You Improve Your Lactate Threshold?
So, how do you improve my lactate threshold so that my racing pace will be faster? Well, this comes through training. Basically, it’s like poking more holes in the bottom of our Dixie cup. If we do that, we can pour water in the cup at a faster rate before it fills up and overflows.
Training at paces which are at approximately your lactate threshold, or faster, will challenge your body to handle the increased production of lactic acid and cause your body to adapt, so the next time you run at a similar pace your body can better handle the increased production of lactic acid.
However, this is something that you should not be doing early in your training program. You need to build up to this. To start you need to be running at a comfortable pace consistently. Then, you need to begin incorporating short repetitions, such as strides, which I will talk about in the next post. These are increased pace runs that last for about 10-15 seconds. As Jack Daniels, running coach and author of Jack Daniels’ Running Formula says, we need to introduce one stress at a time. In going from comfortable pace runs to short repetitions, we are introducing a speed stress. In going from repetitions to longer intervals, such as those to specifically train lactate threshold, we are introducing a cardiovascular stress. In going right from comfortable pace running to intervals we introduce a speed and cardiovascular stress, which can be extremely challenging and increase our risk for injury.
Health Benefits of Improving Lactate Threshold
Improving our lactate threshold will allow us to run at an increased sustained pace, which will result in faster race times. In future posts I will go more into how we can go about increasing our lactate threshold, but for the rest of this post I want to briefly discuss some health benefits of increasing lactate threshold.
In a recent article published in the journal Carcinogenesis, the authors suggest that the improved ability to process lactate, established through training, can lower the incidence of cancer risk. Here is the link to this article:
In this article the authors discuss the contributory role that lactate plays in angiogenesis (the formation of new blood vessels in tumors); how it interferes with the body’s immune response to cancer; and how it creates an acidic microenvironment (the space outside the cancer cell) supportive of cancer metastases, or spread.
Inigo San Millan, lead author of this article, hypothesizes that while people who exercise regularly are at less risk of cancer—in part due to their body’s ability to clear lactate more efficiently—a sedentary lifestyle, combined with excess sugar intake may fuel lactate accumulation and kick-start the metabolic misfiring that can lead to cancer.
Therefore, including training in your program that improves your ability to clear lactate, and thus increases the speed at which lactate threshold occurs, will not only improve your race performance, but may also reduce your risk for the development of cancer.
Please leave your questions in the comment box below. I would love to hear from you!
Inigo San-Millan and George Brooks. “Reexamining cancer metabolism: lactate production for carcinogenesis could be the purpose and explanation of the Warburg Effect”, Carcinogenesis (2017), 38 (2): 119-133.
Scherr J, Wolfarth B, Christle JW, Pressler A, Wagenpfeil S, Halle M. “Associations between Borg’s rating of perceived exertion and physiological measures of exercise intensity.” European Journal of Applied Physiology (2013), 113(1):147-55.