Race time prediction uses known race times to estimate performance at different distances. The most common model is the Riegel formula (T2 = T1 × (D2/D1)^1.06). More sophisticated models like Pete McMillan’s RunSmart and Jack Daniels’ VDOT approach also incorporate VO2 max and training paces. Predictions are most accurate when the known and predicted distances are similar, and when the runner has completed specific training for the target distance. All models become less reliable as distance increases, particularly for the marathon.
Key points
- Riegel formula: T2 = T1 × (D2/D1)^1.06
- Most accurate for similar distances
- Less accurate for marathon (specific training matters)
- McMillan and Daniels provide alternative approaches
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