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.
- Skiba, P. F.: Analysis of Power Output and Training Stress in Cyclists: The Development of the BikeScore(tm) Algorithm, 2008, http://perfprostudio.com/webhelp/studio/scr/BikeScore.htm
- 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.