Show Notes
- Questioning a long standing endurance performance model
VO2max, movement economy, and fractional utilization have traditionally been presented together as key determinants of endurance performance. Yannick and Lars explain what led them to question the evidence behind fractional utilization and take a deeper look at its role.
- Can fractional utilization actually be trained?
After examining endurance and strength training research, the evidence for systematically changing fractional utilization in trained athletes remains inconsistent. The conversation explores why understanding whether a variable can actually be changed matters when calling it a performance determinant.
- When a higher number does not mean better performance
Fractional utilization can increase even when performance declines. The discussion around durability highlights how reductions in VO2max and movement economy after prolonged exercise can produce a higher fractional utilization, complicating the traditional interpretation of the metric.
- What coaches should focus on instead
Rather than targeting a variable we do not yet know how to reliably change, Yannick and Lars point toward factors with stronger evidence behind them, including VO2max, movement economy, consistent training volume, appropriate intensity, and durability.
- Keeping training simple and specific
From perceived effort and day to day variability to repeating key sessions over time, the conversation finishes with practical ways athletes can monitor progress without relying on constant laboratory testing. As Lars puts it, sometimes the best predictor of performance is performance.
