Comparison of Predicted and Measured Power Output During Uphill Cycling

Abstract

Evaluation of competitive cycling performance is often based on either measured power output (PO) or estimates based on equations derived from the literature. In many of the major international cycling events, comparative analyses of performance are common, based solely on prediction equations PURPOSE: To determine the accuracy of published equations for predicting uphill cycling PO vs direct measurements.FigureMETHODS: Well-trained cyclists (n=8) performed 6 rides each (2 courses with different gradients × 3 relative speeds). Each ride was >5 min in duration. Climb equations based on speed, grade, cyclists + bike weight http://www.me.psu.edu/lamancusa/ProdDiss/Bicycle/bikecalc1.htm based on GPS measurements of positional change were used to predict PO. Direct PO was measured using an in-wheel power meter (PowerTap). RESULTS: Predicted PO and measured PO (within the range of 140-400W) were highly related (r=0.989), with an essentially zero value for intercept. CONCLUSIONS: Without correction for wind, altitude or the effect of additional riders, the relationship between predicted and measured PO during cycling was very strong, supporting the value of published climb equations.