In order to produce better shoes that cushion athletes from the high impact forces of running and still provide stability to the foot it is essential to have a method of quickly and reliably evaluating the performance of prototype shoes. The analysis of rear-foot motion requires the use of film or video recordings of test subjects running on a treadmill. Specific points on the subject are tracked to give a measure of inversion or eversion of the heel. This paper describes the testing procedure and its application to running shoe design. A comparison of film and video systems is also discussed.
"Analysis Of Rearfoot Motion In Running Shoes", Proc. SPIE 0693, High Speed Photography, Videography, and Photonics IV, (8 December 1986); doi: 10.1117/12.936752; https://doi.org/10.1117/12.936752