1. What is the Race Time Prediction Formula?

The Race Time Prediction Formula (Riegel's formula) estimates race time for a different distance based on a known performance at another distance. It accounts for the non-linear relationship between distance and running time.

2. How Does the Calculator Work?

The calculator uses Riegel's formula:

Where:

• \( T1 \) — Known time for distance D1 (minutes)
• \( D1 \) — Known distance (km)
• \( D2 \) — Target distance (km)
• \( T2 \) — Predicted time for distance D2 (minutes)

Explanation: The exponent 1.06 accounts for the fact that running speed decreases slightly as distance increases.

3. Importance of Race Time Prediction

Details: Accurate race time prediction helps runners set appropriate pace goals, plan training, and estimate finish times for races of different distances.

4. Using the Calculator

Tips: Enter your best recent time for a known distance, the distance itself, and the target distance you want to predict. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this prediction?
A: The formula is generally accurate within 2-3% for distances between 5km and marathon, assuming similar training and conditions.

Q2: Does this work for very short or ultra distances?
A: The formula becomes less accurate for sprint distances (under 1km) and ultra-marathon distances (over 50km).

Q3: What factors affect prediction accuracy?
A: Course terrain, weather conditions, runner's specific strengths, and recent training focus can all affect actual performance.

Q4: Can I use this for other sports?
A: While developed for running, similar formulas with adjusted exponents can predict performance in swimming and cycling.

Q5: Should I adjust for hills or trail running?
A: For hilly or trail races, add 5-15% to the predicted time depending on elevation gain and terrain difficulty.