Weight & Pace Impact Calculator
Discover how body weight changes affect your running and cycling performance with science-based predictions.
How Weight Affects Performance
The Science Behind Weight & Performance:
- Running: Every 1% of body weight lost ≈ 1% faster on flat terrain
- Moderate hills (5-10%): Weight loss has 2-3x greater impact
- Steep climbs (10-20%): Weight loss has 3-5x greater impact
- Cycling: Power-to-weight ratio is king, especially on hills
- Flat cycling: Aerodynamics matter more than weight
Real-World Examples:
- 8-10%: Typical mountain road (Alpe d'Huez average)
- 12-15%: Steep climbs (Mortirolo, Angliru sections)
- 15-20%: Very steep (Zoncolan, Canton Avenue)
Important Considerations:
- Predictions assume fitness level remains constant
- Rapid weight loss can decrease power and endurance
- Optimal race weight varies by individual
- Focus on sustainable, gradual changes
Need help?
FAQ
Body Weight & Race Performance
Generally, for every pound lost, runners can expect to gain 1–2 seconds per mile. Our calculator personalizes this for your weight and terrain.
Absolutely! On climbs, every pound saved can shave off significant time. Use our tool to estimate your specific benefit.
Yes! Our human coaching programs help you safely reach target race weight without risking power or health.
