Gradescale

Power-Duration Curve

Fit Critical Power, W′, and modeled FTP from your best efforts using a domain-aware hybrid model

Inputs

Peak sprint — anchors Pmax

Anchors the aerobic ceiling

Anchors Critical Power + modeled FTP

Enter at least two efforts, including two of 3 minutes or longer. A 5-minute and a 20-minute effort give the most reliable Critical Power fit.

Results

Critical Power (CP)284W
W′ (anaerobic capacity)22.8kJ
Modeled FTP280W
Peak power (Pmax)946W

Modeled curve vs your efforts

5s1min5min1h02505007501000W

Data quality

  • • CP is poorly determined: only 4 maximal efforts between 2 and 30 minutes remain after paced rides were set aside, and the model fits 4 parameters. Treat 284W as a rough figure until you have more hard efforts in that range
  • • Domain gap: no efforts > 30 min; heavy-domain decay model unconstrained
  • • High model error: SEE = 34W (threshold: 20W)

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