Have Zwift made it easier for light riders on the flat?

Yes, then it is probably this formula: Pack Dynamics 4 Release [April 2023] - #518 by OleKristian

A = 0.0293 * H^0.725 * M^0.425 + 0.0604

I missed that exponent on height (H). My bad.

The height “bonus” the exponent gives, can be visualized like this:

A rider who is 190 cm tall will experience about a 4-5% height factor reduction compared to a rider who is 160 cm tall. The impact of height isn’t directly proportional, but it’s close.

Compared to other formulas:

Debraux et al. (2011): 0.634 (A=0.452×H^0.634)
Heil (2001): 0.396 (A=0.266×H^0.396×M^0.364)

It seems that the height factor can be given too much weight in the formula.

All I’m saying is that these formulas work very differently and probably have a high error rate outside the ranges of the data they are based on and that this can explain why Zwift’s calculation of force can feel unfair/not real in some cases.

1 Like