Runners love their jargon. From DOMS to bonking, VO2 max to strides, there is undoubtedly a rich running vernacular, and knowing how to properly use the terms—both in conversation and in training practice—can help you feel like a real runner.
While not every term that could be in a running glossary is necessarily one you want or need to familiarize yourself with, one of the most important training terms you’ll want to understand and incorporate into your routine is threshold training.
A threshold run is one of the key types of running workout designed to help you run faster and increase your fitness. They should be a regular part of your training program, no matter where you are in your fitness journey.
That said, many runners aren’t exactly sure what threshold runs or their benefits are, or how to do threshold training in general. This leads to ineffective runs or a reluctance to try these types of workouts altogether.
In this guide, we’re going to look at:
- What Is Meant By “Threshold”?
- What is a Threshold Run?
- How to Find Your Threshold Run Pace
- Benefits of Threshold Runs
- How to Do Threshold Runs
- How to Incorporate Threshold Runs Into Your Training
If you want to get faster and stronger, keep reading for everything you need to know about threshold runs.
What Is Meant By “Threshold” When Considering Threshold Runs?
We used to think that the lead-like, burning, heavy feeling you get in your legs in the last mile of a hard 5k or last lap of an all-out mile was a result of “lactic acid” buildup in the legs. When your effort level and running pace reach a certain point, you’ll notice you suddenly become a lot more breathless.
This point, called the ventilatory threshold, is the point at which your body is no longer able to get enough oxygen when you breathe and it is closely tied to what is called the lactate threshold.
The lactate threshold is considered the tipping point wherein your body has to start producing energy anaerobically (without oxygen) through the metabolic pathway known as glycolysis rather than through aerobic metabolism.
Glycolysis produces an end product called lactate, and while the lactate itself isn’t actually what causes the heavy, burning feeling, lactate production is associated with the production of hydrogen ions and other waste products that do cause discomfort and muscular fatigue.
At the lactate threshold, your body suddenly shifts from being able to clear the lactate and deleterious metabolic waste products at the same rate they are being produced to becoming inundated with waste due to the increased reliance on producing energy without sufficient oxygen.
Why Do We Care About Lactate Threshold
The lactate threshold in and of itself isn’t necessarily helpful, but knowing your running pace at your lactate threshold tells you how fast you can run before tipping the scales past “the point of no return.”
In other words, if you’re running a marathon or long-distance race, and can keep your pace at or below your lactate threshold pace, you’ll be able to stave off crippling fatigue.
What is a Threshold Run?
In simple terms, a threshold run is when you run at or just below your lactate threshold pace where your body is still able to clear the lactate from your body so you don’t reach complete exhaustion.
How to Find Your Threshold Run Pace
There are several different ways you can find your threshold run pace.
Of course, the most precise and accurate method is to get tested in an exercise physiology lab with blood lactate testing, but this is invasive and can be expensive.
If you’ve done a VO2 max test, your lactate threshold occurs around 83-88% of your VO2 max, so your threshold run pace would be the pace you are running at 83-88% of your VO2 max according to your lab results.
60-Minute Effort Pace
Your threshold pace is roughly the pace you could hold at max effort for an hour of running. In other words, if you were to enter a race that was measured in time instead of distance, and the goal was to run as far as you could in one hour, the pace you could hold for that one-hour race would be a good estimate of your threshold run pace.
Approximating from Race Results
For most runners, the threshold run pace is somewhere between 10k-15k race pace.
Threshold run pace can be determined by the pace you’re running when your heart rate is about 75-80% of your maximum heart rate.
Rate of Perceived Exertion
A less precise estimate of your threshold training pace is to use the pace you’re running when your rate of perceived exertion (RPE) is about 7-8 out of 10, where 10 is an all-out sprint.
Benefits of Threshold Runs
One of the best things about the lactate threshold is that research has demonstrated that it’s modifiable through training. Threshold runs can push the lactate threshold to faster paces, meaning that you can maintain a faster pace while still relying on aerobic metabolism, without accumulating the byproducts of glycolysis. This means you can run faster and farther without fatigue.
Additionally, threshold runs improve your overall aerobic fitness and your VO2 max. They train your body to be more metabolically efficient and can improve the ability to use fat for energy at faster paces.
How to Do Threshold Runs
Threshold training involves any workout where you’re maintaining your threshold pace for a certain period of time. A threshold run may involve one continuous interval at threshold training pace or several shorter intervals with slower recovery rest periods in between.
However, because threshold pace isn’t an all-out effort, rest periods should be short. Here are some sample threshold workouts:
- Run a 1-2 mile warmup, 3-8 miles at threshold pace, and then 1 mile cool down.
- Run a 1-2 mile warmup, then 3-6 x 1 mile at threshold run pace with one minute easy in between, and then 1 mile cool down.
- Run a 1-2 mile warmup, then 3 x 10-15 min at threshold run pace with one minute recovery in between, and then 1 mile cool down.
- Run a 1-2 mile warmup, then 2 x 20 min at 10k pace, or slightly faster than threshold run pace with 90 seconds of recovery in between, and then 1 mile cool down.
- Run the last 2-4 miles of a long run at threshold pace.
How to Incorporate Threshold Runs Into Your Training Program
Depending on your goals and current fitness levels, most coaches recommend doing at least one threshold workout per week.
More advanced runners may choose to have one dedicated tempo run at threshold pace as well as a second weekly workout with intervals at threshold pace, or may incorporate threshold pace work into a long run.
Even beginners can safely and effectively incorporate threshold runs into their workout program, as threshold pace is individualized. Moreover, runners who are less aerobically fit will experience more significant improvements in lactate threshold through threshold training than experienced runners.
As your fitness improves, you’ll notice your threshold run pace starts to feel easier. This is indicative of an increase in your lactate threshold, meaning your training is working! You will need to recalibrate your threshold run pace as you improve.
The Takeaway: Threshold Runs
Threshold training improves your ability to produce energy without having lactate build-up in your muscles. In other words, threshold runs train your body to handle faster paces without producing the metabolic byproducts that make muscles feel like they’re on fire.
Your threshold run pace is somewhere between your 10k-15k pace, or about the pace you can hold for one hour. Threshold workouts involve extended intervals at threshold pace.
Calculate your threshold pace and add some specific threshold training to your running program and you’ll see how quickly you’ll reap the benefits!