During a cycling time-trial, the time difference in performance between elite athletes can be small. At racing speed greater than 14 m/s, aerodynamic drag represents 90% of the overall resistive forces. This force is directly proportional to the projected frontal area of the cyclist and bicycle.
The projected frontal area represents the portion of a body which can be seen by an observer placed exactly in front of that body. To date, the most common method used to measure the frontal area is the digitalisation method that needs to take a photograph of the cyclist and a calibration frame (The Gold Standard). But some authors have described different handicaps of this method. For example it is a static procedure, too much time to get the results, no possibility to give a real-time feedback and the possibility to introduce some errors in a 2D analysis.
To solve these problems, a new methodology has been created using EXPERIMEDIA’s 3D technologies building on the Kinect sensor. The approach allows analysis of the frontal area of the cyclists during pedaling in real-time taking into account depth information (3D analysis), i.e. measuring the real area of every part of the body of the cyclists, not projecting in a 2D plane.
The 3D Media in Sports experiment conducted an initial opportunity assessment with individual cyclists to explore feasibility. The early results were extremely positive, identifying sufficient value for experimenters to invest further effort in a scaled up experiment aiming to collect sufficient data for scientific evidence. This process of scaling experiments from opportunity assessment through to industrialisation is at the heart of experimentation at EXPERIMEDIA using the Value Impact Assessment.
CAR conducted a new trial with 11 cyclists of the Team Movistar Ecuador assessing three different positions: upright position, dropped position and aerodynamic position, giving an aerodynamic profile for every cyclist in every position. The trial was performed in collaboration with researchers from two different Universities, University of Barcelona and Blanquerna University ).
The experiment procedure applied the new 3D method and the Gold Standard “digitalisation method (2D)“ in order to compare results. Both methods produced reliable measures for the all three positions. High correlations between measurements for upright and dropped positions where observed with some deviation in the aerodynamic position. Full results will be published in a scientific journal in a near future. The new method is a step forward in the assessment of the aerodynamic profile of the cyclists. It could be applied by many bike fitters because it is reliable, low cost technology and easy to use.