Negative split running means covering the second half of a run or race faster than the first half. Use the prediction as a pacing starting point, then adjust it for recent training, course profile, weather, and how similar the input race is to the target distance.
What a Negative Split Is
A negative split happens when the second half is faster than the first half.
It is often used to avoid early overpacing and finish with better control.
When It Helps
Negative splits can work well in races where starting too fast is a common mistake.
They are also useful in workouts that teach patience and late-race strength.
How to Plan One
Start slightly slower than average goal pace, settle into rhythm, then increase effort gradually.
Do not make the first half so slow that the second half requires an unrealistic surge.
Compare Pacing Strategies
Method and Sources
How this page is checked
- Race prediction pages use a Riegel-style endurance model with exponent 1.06.
- Predictions work best when the input result is recent, measured, and similar enough to the target race distance.
- Heat, hills, altitude, fueling, pacing, injury, and training history can make the predicted time too aggressive or too conservative.
Sources
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