Int. j. environ. res. public health Int. j. environ. res. public health The Impact of Grounding in Running Shoes on Indices of Performance in Elite Competitive Athletes Muniz-Pardos Borja Universidad de Zaragoza Zelenkova Irina Universidad de Zaragoza Gonzalez-Aguero Alex Universidad de Zaragoza Knopp Melanie Boitz Toni Graham Martin Ruiz Daniel Casajus Jose A. Universidad de Zaragoza Pitsiladis Yannis P. 2022 research-article