Running Economy (kcal per km)
kcal/km ≈ 0.97 × bodyweight (kg). Foundational metric for marathon fueling.
Result
Total energy
679 kcal
67.9 kcal/km.
- Body weight70 kg
- Distance10 km
- Factor0.97
- kcal/km67.90
- kcal/mi109.25
- Total kcal679.0
Step-by-step
- kcal/km = 0.97 × 70 = 67.90.
- Total = 67.90 × 10 = 679.0 kcal.
How to use this calculator
- Enter weight + distance.
- Pick efficiency tier.
About this calculator
Running burns approximately 1 kcal per kg per km regardless of pace (over reasonable speeds). Elite runners are ~5% more efficient (0.92 kcal/km/kg) due to cleaner mechanics. A 70 kg runner burns ~68 kcal/km × 42.2 km marathon = ~2870 kcal. Glycogen stores ~2000 kcal max — why marathon fueling (gels, drinks) is critical past mile 18.
Frequently asked
For total energy: roughly true at typical running speeds. Walking burns less; sprinting more per km.
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