If you’ve been in the running world for a while, you’ll likely have heard the terms “lactate,” “anabolic,” “aerobic,” and “anaerobic” thrown around quite a bit. And, while most runners know that increasing their anabolic (or lactate) threshold is good, many don’t know what it is or how to improve it.
Your lactate threshold is the fastest pace you can run at a steady state without fatiguing. Three ways you can improve your lactate threshold are by doing tempo runs, lactate threshold workouts, and increasing your weekly mileage.
Below, we’ll discuss everything you need to know about the various thresholds, what they mean for your performance, how to increase your lactate threshold, why it’s important to improve your threshold, and what workouts you can do to increase your anabolic threshold.
NOTE: For the purpose of this article, we’ll use anabolic and lactate interchangeably as they mean the same thing.
So, let’s jump right into it:
What Exactly Is Lactate?
Before diving into what your anabolic threshold is, we’ll first see what lactate, or lactic acid, is and why it matters. Grab your science hat for a second while we go through this – it’s less complicated than it seems, so bear with us.
When running or performing strenuous exercise, your muscles require energy to move, contract, and exert. The energy to perform comes from a molecule called ATP (adenosine triphosphate – try saying that quickly three times). This molecule can be produced through various metabolic pathways based on workout intensity, oxygen availability, available fuel sources, and type of muscle fiber.
When performing a high-intensity exercise, like running quickly, your body makes ATP through anaerobic (without oxygen) metabolism. One of the upsides of anaerobic metabolism is that it’s a fast way to create energy, so if you need a lot of energy in a short span, your body does this with anaerobic metabolism.
High-intensity tasks cause our bodies to break down glucose to generate ATP when there’s no oxygen available. In doing this, our bodies produce lactate, or lactic acid, an organic acid.
You may be wondering how creating this acid in our bodies is tied to better performance, but to explain that, we need to look at lactate threshold.
What is Lactate Threshold?
Your lactate threshold, often also referred to as anaerobic or anabolic threshold, is the point where your blood lactate levels increase dramatically due to increased exercise intensity.
When you’re below or at your lactate threshold, your body can metabolize or clear lactate at the same rate that it’s being produced. This means you won’t have any noticeable increase in blood lactate levels.
When you exercise at high intensities or run at high speeds above your lactate threshold, the muscles produce lactate faster than your liver’s ability to convert it, causing a noticeable increase in blood lactate levels.
The body is minimally reliant on anaerobic glycolysis for energy when exercising at lower intensities. This is because there’s sufficient oxygen for your muscles to create energy, and the oxygen consumption rate in the muscles is low, allowing the muscles time to meet the energy demand.
While glycolysis occurs during lower-intensity activities, your body can shuttle the lactate out of your muscles at the same rate it’s being produced, maintaining the blood lactate levels at a stable level.
Blood lactate levels are usually around 1-2 mmol/L during low-intensity exercise.
Once you start exercising more intensely at a pace or level corresponding to your lactate threshold, your muscles require more energy than what your aerobic metabolism can provide.
To keep up with the energy required to move at the pace you are going, your muscles ramp up glycolysis. Exercise at this point also becomes very uncomfortable, and you won’t be able to breathe steadily.
Your blood lactate levels are usually at or over 20 mmol/L at the lactate threshold.
When you run at a pace past your lactate threshold, you will feel a burning in your legs, and you will rapidly fatigue. It’s important to note that your legs aren’t burning due to the lactate but rather the hydrogen ions in your blood.
Blood lactate levels are an important biomarker of the acid accumulating in your muscles. Hydrogen ions cause discomfort and fatigue at the same rate as lactate. Your lactate threshold is a great indicator of the point when performance-inhibiting hydrogen ions rapidly accumulate, causing the burning sensation in your legs.
All of this means that your lactate threshold is the fastest pace you can run at a steady state without fatigue.
Why Should You Increase Your Lactate Threshold?
The simple reason is that the higher your lactate threshold, the longer you can hold a more intense pace and the faster you can run before you fatigue. Your lactate threshold corresponds with your running performance in higher-intensity distance running.
Tempo runs and lactate thresholds allow you to increase your lactate threshold over time. Research has shown that average lactate threshold values are as below:
If you don’t know your VO2 max, we recommend using our handy calculator. Once you know your VO2 max, you can calculate your lactate threshold.
NOTE: The only true way to know your exact VO2 max and lactate threshold is by doing tests in a sports science lab. These are tools to give you a rough estimation.
Determining Your Lactate Threshold
We gave you a basic idea above and mentioned that an accurate lactate threshold requires professional sports lab testing. Still, you can calculate your rough number by doing a fairly challenging albeit simple field test.
Before getting started, you’ll need to wear a heart rate monitor. If you don’t have one, borrow one from a friend. While running watches are great for tracking your distance and time, their heart rate monitors are not what they’re known for. You need a chest heart rate monitor for the accuracy it offers.
Next, let’s look at how to calculate your lactate threshold as you run:
- Do a warm-up jog at an easy pace for 15 minutes.
- Build up into a pace at your maximum steady state (the pace just before you cross into threshold effort). Hold this effort for 10 minutes.
- Start a timer for 20 minutes and hold this pace for the duration. Record your heart rate for this 20-minute segment.
- Do a gentle cool-down jog at an easy pace for 10 minutes.
The average pace you could maintain for those 20 minutes is your rough lactate threshold pace. The heart rate average for those 20 minutes is the estimated heart rate corresponding to your lactate threshold.
How to Improve your Lactate Threshold
Improving your lactate threshold isn’t easy or comfortable, but it will benefit you in the long run (no pun intended). Three main methods are used to improve your threshold.
The first is tempo runs. If you’ve been running for a while (long enough to want to improve your lactate threshold), it’s unlikely you haven’t heard of a tempo run. A tempo run involves continuously running at a set pace for the duration of the run. The pace should be an RPE of 7 or 8 (a hard pace that’s sustainable for around 20 to 30 minutes).
An example of a tempo session would be a 15-minute warm-up at an easy pace, then run at your lactate threshold pace (as above) for 30 minutes, followed by a 10-minute cool down at an easy pace.
If you’ve just started working with your lactate threshold, tempo runs, and higher RPEs, do the tempo segment for 10 minutes, focusing more on holding the same pace throughout. Once you’ve achieved this, build up the time you hold the pace until you can do it for 30 minutes.
Lactate Threshold Workouts
We’ve said it many times – one way to run fast is to practice running fast. And that’s what lactate threshold workouts call on you to do. A lactate threshold workout is basically a type of interval workout. They involve running at the pace or heart rate corresponding to your lactate threshold (which we discussed earlier).
This can be done with various repeats, including:
- 4 x 5 minutes at threshold pace with 2 minutes recovery (beginner)
- 5 x 4 minutes at threshold pace with a 90-second recovery (intermediate)
- 2 x 10 minutes at threshold pace with 4 minutes recovery (intermediate and advanced)
- 4 x 8 minutes at threshold pace with 3 minutes recovery (advanced)
You only need to do one weekly lactate threshold workout – doing more increases your risk of injury and burnout. This weekly workout will condition your body and make it more efficient and comfortable at creating energy using aerobic metabolism during higher intensities. This increases your lactate threshold.
Increase Your Weekly Mileage
This simple method may be surprising, but you can improve your lactate threshold by increasing your weekly mileage. This increase makes the mitochondria (the cells which generate ATP to provide your muscles with energy) more efficient at providing energy to your body as you run.
These cellular changes improve your lactate threshold, allowing you to run harder, faster, and longer.
A lot of the time, runners make the simple mistake of just not running enough, which means they aren’t developing their aerobic capacity, the foundation that the rest of their fitness is built on.
When you increase your weekly mileage, prioritize increasing the volume of your easy runs – stay running at an easy pace, just tack on a few miles to each. Don’t increase your tempo or interval running distances.
Benefits of Lactate Threshold Training
There are so many upsides to including lactate threshold training in your running plan. Below we’ll look at some of the many benefits.
- Improve the efficiency of muscle fibers
- Increase your blood plasma volume
- Convert type 2b muscle fibers to type 2a
- Increase the concentration of mitochondrial enzymes
- Stimulates the increase of aerobic conditioning and capacity
- Increase your muscle glycogen storage
- Improve muscle capillary density
- Increase your aerobic metabolism efficiency
- Strengthen type 1 muscle fibers
- Increase your cardiac output and stroke volume
- Improve your muscle fiber recruitment
Lactic acid, anabolic lactate threshold, and lactate are some of the most misunderstood concepts among runners and sportspeople. Lactate is more than just a metabolic byproduct – it’s a critical metabolic component and vital fuel source.
Now that you know how to increase your lactate threshold and why this is important, you can make the correct changes to your running plan to ensure you aren’t overdoing or underdoing it.