If you’re serious about marathon training, you’ve probably heard about tempo or threshold runs. These workouts are often called the “bread and butter” of endurance training, and for good reason. They are essential for improving stamina, increasing lactate threshold, and making marathon pace feel more sustainable. But what exactly are threshold runs, and why should they be a key part of your training plan?

What Are Threshold Runs?

Threshold runs are sustained efforts run at or slightly below your lactate threshold—the point at which your body starts accumulating lactate faster than it can clear it. This intensity is typically around 80-90% of your max heart rate or the effort you can hold for about an hour in a race setting. A common way to gauge threshold pace is to run at a “comfortably hard” effort. One where you can still speak in short phrases but not hold a full conversation. If you have a goal marathon pace, these running sessions should be faster than your goal running time.

Why Are Threshold Runs Important for Marathon Training?

1. Increases Lactate Clearance Efficiency
   • The higher your lactate threshold, the faster you can run without accumulating excessive muscle fatigue. Training at this intensity teaches your body to clear lactate more efficiently, helping you maintain your pace longer and not hitting the wall (or trying to avoid hitting the wall)
2. Builds Aerobic Strength
   • Marathons require a high level of aerobic endurance. Threshold runs push your aerobic system to adapt, leading to improvements in overall stamina and efficiency.
3. Prepares You for Marathon Pace
   • While your marathon pace is slower than your threshold pace, consistently training at a slightly harder effort makes marathon pace feel more manageable on race day.
4. Improves Mental Toughness
   • Running at a “comfortably hard” pace for extended periods helps build the mental resilience needed to push through fatigue in the later miles of a marathon.

How to Incorporate Threshold Runs into Your Training

• Classic Tempo Run:
  • Warm-up with 10-15 minutes of easy running
  • 20-40 minutes at threshold pace
  • Cool down with 10-15 minutes of easy running
• Threshold Intervals:
  • 3-5 x 10 minutes at threshold pace with 2-minute easy jogs between
  • 12 x 400m repeats at threshold pace with 2-minute easy jogs between
  • 5 x 1 mile repeats at threshold pace with 2-minute easy jogs between
• Progression Runs:
  • Start at an easy pace and gradually increase to threshold effort for the final 15-20 minutes

Tips for Executing Threshold Runs Effectively

• Use heart rate (80-90% of max HR) or perceived effort to gauge intensity.
• Run by feel rather than strict pace, especially on varied terrain.
  • I do a lot of my threshold work on a treadmill or a track so I can track the speed easier and reduce the variability of the terrain
• Focus on controlled effort rather than maxing out; threshold runs should challenge you but not leave you completely exhausted.
• Space these workouts appropriately in your plan, typically 1-2 times per week with proper recovery in between.
  • As your running ability improves, you might feel the need to increase these runs.
  • I incorporate uphill sustained efforts, which also function similarly to a threshold run.

Threshold runs are one of the most effective ways to boost your endurance, efficiency, and ability to hold race pace for longer. By incorporating them into your marathon training consistently, you’ll develop the strength and resilience needed to perform at your best on race day. Next time you lace up your running shoes, embrace the challenge of the threshold run; it could be the key to unlocking your marathon potential!

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Are you incorporating threshold runs into your training?