Threshold training is one of the most powerful tools a runner can use to get faster and build lasting endurance. It sits right at the edge of your comfort zone—just below the point where your body begins to fatigue faster than it can recover.
Running at this “threshold” effort teaches your body to clear lactate more efficiently, allowing you to sustain harder efforts for longer periods. In simpler terms, it helps you hold a faster pace with less strain.
Whether you’re training for a 5K or a marathon, incorporating threshold runs regularly can dramatically improve your aerobic capacity, running economy, and mental toughness. They build the bridge between your easy miles and your top-end speedwork.
If you’re serious about becoming a stronger, more efficient runner, understanding and executing threshold training correctly is essential. In this guide, we’ll break down what threshold runs are, why they work, and how to incorporate them into your training plan safely and effectively.
Understanding the Lactate Threshold: Where Your Body Reaches Its Breaking Point
We used to think that the lead-like, burning, heavy feeling in your legs during the last mile of a hard 5K or the last lap of an all-out mile resulted from “lactic acid” buildup.
When your effort level and running pace reach a certain point, you’ll notice you suddenly become much more breathless. This point, called the ventilatory threshold, is the point at which your body can no longer get enough oxygen with each breath, and it is closely tied to the lactate threshold.
The lactate threshold1Hoff, J., Støren, Ø., Finstad, A., Wang, E., & Helgerud, J. (2016). Increased Blood Lactate Level Deteriorates Running Economy in World Class Endurance Athletes. Journal of Strength and Conditioning Research, 30(5), 1373–1378. https://doi.org/10.1519/jsc.0000000000001349 is considered the tipping point at which your body must start producing energy anaerobically (without oxygen) via the metabolic pathway glycolysis rather than 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 lactate and other deleterious metabolic waste products at the same rate they are produced to becoming inundated with them due to the increased reliance on producing energy without sufficient oxygen (anaerobic 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 can still clear lactate so you don’t reach complete exhaustion.
Threshold runs are also often called tempo runs, since threshold pace is sometimes referred to as tempo pace.
How Can I calculate My Threshold Pace?
There are several ways to find your threshold pace:
#1: Get A Lab Test
The most precise and accurate method to calculate your threshold pace 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.
#2: Calculate Your 60-Minute Max 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 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.
#3: Use Recent Race Results
For most runners, threshold pace is somewhere between 10K and 15K race pace.
You can also take the results of these races or run a 3K or 5K time trial at a very hard effort, and then pop those race times into Jack Daniel’s VDOT running formula.
Here, you will calculate all of your current training paces, including interval training paces, half-marathon paces, marathon paces, threshold paces, etc.
#4: Use Your Heart Rate Training Threshold Zone
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.
#5: Use 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 6 out of 10, where 10 is an all-out sprint.
What Are The Benefits of Lactate Threshold 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 for a longer period of time without fatigue.
Additionally, threshold runs improve overall aerobic fitness and VO2 max. They train your body to be more metabolically efficient and can improve your ability to use fat for energy at faster paces.
Related: What’s a Good VO2 Max? Average VO2 Max By Age And Sex
How Do You Structure A Threshold Workout?
Threshold training2Burke, J., Thayer, R., & Belcamino, M. (1994). Comparison of effects of two interval-training programmes on lactate and ventilatory thresholds. British Journal of Sports Medicine, 28(1), 18–21. https://doi.org/10.1136/bjsm.28.1.18 involves any workout in which you maintain your threshold pace for a certain period of time. A threshold run may involve one continuous interval at the threshold training pace or several shorter intervals with slower recovery rest periods in between.
However, because the threshold pace isn’t an all-out effort, rest periods should be short. Here are some sample threshold workouts:
#1: Continuous Tempo Run
- 10–20 min warm-up
- 25–60 min at threshold effort (a sustainable hard pace you can sustain for about an hour)
- 5–10 min cool-down
#2: Broken Threshold Repeats
- 10–20 min warm-up
- 3–6 x 6–8 min at threshold pace with 1-3 min easy jog recovery between reps
- 5–10 min cool-down
#3: Long Threshold Intervals
- 10–20 min warm-up
- 3 x 10–15 min at threshold pace with 1-3 min easy jog between reps
- 5–10 min cool-down
#4: Extended Effort (10K Effort Focus)
- 10–20 min warm-up
- 2 x 20 min at 10K effort (slightly faster than threshold) with 90 sec easy jog between
- 5–10 min cool-down
#5: Long Run with Tempo Finish
- Run your regular long run
- Finish the final 20–40 min at threshold pace
How Do I Incorporate Threshold Runs Into My Training Plan?
Depending on your goals and current fitness levels, most coaches recommend doing one threshold workout per week.
More advanced runners may choose to have two threshold workouts per week: one dedicated tempo run at threshold pace and a second weekly workout with intervals at threshold pace, or incorporate threshold pace work into a longer-distance long run.
Even beginners can safely and effectively incorporate threshold runs into their workout program, as threshold pace is individualized.
Moreover, less aerobically fit runners will experience more significant improvements in lactate threshold through threshold training than more experienced distance runners.
As you become fitter, you’ll notice your threshold effort 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.
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.
Calculate your threshold pace and add specific threshold training to your running program —you’ll see how quickly you reap the benefits!
To spice up your training plan with even more types of workouts, check out our interval training guide:
Hi. Merry Christmas! Thank you for an excellent post. I use Threshold training in my coaching, but i now have a far better understanding of the training tool. Thank you, Allen.