Threshold pace
Threshold pace is the fastest running pace you can sustain for roughly an hour without a steady build-up of fatigue. For many runners it falls between their 10K and half-marathon race pace, and it is the reference point for pace-based running zones.
How to find your threshold pace
A field test is the simplest route: warm up well, then run 20 minutes as hard as you can hold evenly on flat ground. Your average pace for the 20 minutes is a good estimate of threshold pace, and your average heart rate is a good estimate of threshold heart rate. A recent race works too — a 10K run flat out is close to threshold effort for many runners.
Why it matters
Training just around threshold — tempo runs and cruise intervals — raises the pace you can hold before fatigue builds, which is what improves race times from 10K to the marathon. Knowing the number keeps easy runs easy and hard sessions at the intended effort.
In The Next Race
The Next Race's running plans open with a 20-minute threshold test. Save the pace, and the app turns it into your run pace zones and estimates every planned run from them.