Critical Power (CP) modeling

Edited

Critical Power (CP) modeling offers a comprehensive view of cycling performance, focusing on three key metrics:

  1. Critical Power (CP): The maximum power an athlete can sustain without rapid fatigue, marking the threshold between steady and non-steady exercise.

  2. Available Work Capacity (W’): Represents the finite amount of work (in Joules) an athlete can perform above CP. Once W’ is exhausted, sustaining power above CP becomes unfeasible.

  3. Max Power: The peak power achieved over a 5-second sprint, reflecting short-term anaerobic capacity.

Why Vekta Uses CP Over FTP

While FTP estimates a cyclist’s sustainable power over an hour, Vekta prioritizes CP for its accuracy across multiple durations. CP is derived from a scientifically grounded model, providing:

  • Mathematical Rigor: Using a range of max efforts, CP better represents both aerobic and anaerobic capacities.

  • Enhanced Robustness: CP reflects sustained and high-intensity efforts, adapting more effectively to real-world performance variations than a single FTP estimate.

How Vekta Computes CP, W’, and Max Power

Vekta’s model continuously adapts by analyzing recent max efforts. This dynamic approach reflects ongoing performance shifts, with algorithms that:

  • Incorporate Varied Durations: Vekta’s adaptable algorithms use different max-effort intervals to create an accurate power profile.

  • Track Performance Trends: Regular updates based on recent data capture changes in fitness and endurance, helping predict future performance.

Classic CP Test Protocol

A common CP testing protocol includes:

  • 15-second Max Power: Measures peak anaerobic output.

  • 3-minute Max Effort: Captures short-term power.

  • 12-minute Max Effort: Contributes to CP calculation for sustained power.

With CP modeling, Vekta offers a scientifically robust performance framework, allowing cyclists to track improvements, optimize training, and achieve a more complete understanding of their endurance and power potential.


Further Reading

  • Morton, H.R. (1996): A 3-parameter critical power model. Ergonomics, 39(4), 611–619.

  • Leo P et al. (2022): Power profiling and the power-duration relationship in cycling. Eur J Appl Physiol.

  • McGrath, E., Mahony, N., Fleming, N., Raleigh, C., & Donne, B.: Do Critical and Functional Threshold Powers Equate in Highly-Trained Athletes? Human Performance Laboratory, Departments of Anatomy and Physiology, School of Medicine, Trinity College Dublin.