Unstable shoes: functional concepts and scientific evidence Benno Nigg, Peter A. Federolf, Vinzenz von Tscharner & Sandro Nigg Footwear Science; Volume 4, Issue 2, 2012 Quote: The purpose of this study was to discuss (a) the conceptual idea behind unstable footwear and (b) the validity and scientific support of some selected claims made with respect to unstable shoes