Fig. 2. Schematic representation of the interactions within the three-party system. Schematic representation of the interactions within the three-party system. The system is based on three elements including running patterns, running speeds, and biomechanical parameters. Each element can evolve through continuums and lead to different optimization strategies. Finally, the strategies seem to be mediated by the feeling of pleasure-displeasure. Thibault Lussiana, and Cyrille Gindre Biology Open 2015;bio.014886 © 2015. Published by The Company of Biologists Ltd