Race Predictor
Predict finish times across any distance using your recent race performance
Input Parameters
Real-time calculation updates dynamically as you adjust inputs. Values remain strictly local on your device.
Predicted Marathon FinishRiegel Model
3:47:47HH:MM:SS
Pace: 05:24 min/km (08:41 min/mile)
| Target Race | Distance | Predicted Time | Required Pace |
|---|---|---|---|
| 5K | 5.0 km | 23:45 | 04:45 min/km |
| 10K | 10.0 km | 49:31 | 04:57 min/km |
| Half Marathon | 21.0975 km | 1:49:15 | 05:11 min/km |
| Marathon | 42.195 km | 3:47:47 | 05:24 min/km |
Clinical Responsibility Note: This calculation provides statistical estimations for informational and educational purposes only. It is not an individualized medical diagnosis or clinical prescription.
Mathematical Formula & Scientific Methodology
Formula: Riegel Endurance Power Law
T2 = T1 × (D2 / D1)^1.06Published in American Scientist (1981) by research engineer Peter Riegel, widely adopted by Runner's World and World Athletics.
Model Assumptions
- Sufficient aerobic base training appropriate for the target distance
Variables & Standard Units
| Symbol | Physiological Meaning | Unit |
|---|---|---|
| T1, D1 | Known baseline time and distance | dimensionless |
| T2, D2 | Target predicted time and distance | dimensionless |
| 1.06 | Riegel fatigue coefficient modeling natural aerobic decay over distance | dimensionless |
Scientific Limitations
- Predicting a marathon from a 5K requires sufficient weekly mileage; otherwise, aerobic endurance limits actual performance
Frequently Asked Questions
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