Glossary: xPower

xPower is a weighted average of your power output and serves as an alternative stress metric. It accounts for non-instantaneous physiological responses of the body to changes in intensity.

xPower is always greater than or equal to your average power. For a steady ride (or run), both will be equal. For a non-steady ride (or run) xPower is the best guess at your average power if you did a steady ride (or run) with the exact same effort.

xPace and xGAP are determined in the same way as xPower.

See also


  1. Skiba, P. F.: Analysis of Power Output and Training Stress in Cyclists: The Development of the BikeScore(tm) Algorithm, 2008,
  2. Clarke, D. C., Skiba, P. F.: Rationale and resources for teaching the mathematical modeling of athletictraining and performance, Advances in Physiology Education, volume 37, pp. 134–152, 2013, doi: 10.1152/advan.00078.2011.

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