Running Race Time Predictor Calculator (Riegel Formula 5K to 42K)
Running physiological performance audit. Uses Peter Riegel's endurance fatigue model (T2 = T1 × (D2/D1)^1.06) to project realistic race finish times across all distances based on your recent PR.
Input Parameters
Instant Calculation Result
Adjust values on the left to calculate live results.
In-Depth Guide & Mathematical Methodology
🏃 Understanding Riegel's Race Prediction Model
Assumptions: The 1.06 fatigue exponent assumes you have trained with sufficient weekly mileage and endurance long runs for the target distance.
Pacing Strategy: Running negative splits (second half slightly faster than first half) maximizes your chances of hitting your Riegel target time.
Frequently Asked Questions (FAQ)
What is the Running Race Time Predictor Calculator (Riegel Formula 5K to 42K) and how does it work?
Running physiological performance audit. Uses Peter Riegel's endurance fatigue model (T2 = T1 × (D2/D1)^1.06) to project realistic race finish times across all distances based on your recent PR.
How do I use this Running Race Time Predictor Calculator (Riegel Formula 5K to 42K)?
Select your recent reference race distance (5K, 10K, or Half Marathon). Enter total race finish time achieved (in minutes). View projected finish times and per-km target paces for 5K, 10K, 21K, and Full Marathon.
What mathematical formula is used in this calculation?
Riegel Aerobic Fatigue Formula (1977): T2 = T1 × (D2 / D1) ^ 1.06. Fatigue exponent 1.06 validated for distance runners with adequate weekly volume.
Is the Running Race Time Predictor Calculator (Riegel Formula 5K to 42K) on FindCalculator free to use?
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