The best way to analyse a riders efficiency is to observe and measure the rider while he or she is pedalling on the bike. Retul 3 d motion capture technology simultaneously measures three planes of movement on the rider as he or she is in motion. Retul averages the risers pedal strokes to provide a comprehensive data set reflecting the riders movements. The data obtained at this point allows the Retul technician to properly evaluate changes to a riders positions. Attempts to analyse the rider in a static position, or only in two dimensions, will not provide data at the same level of accuracy as 3D motion capture.