Fig. 2. The paths of the musculotendon actuators making up the frog model. The muscles include semimembranosus (SM), gracilus major (GR), adductor magnus dorsal and ventral heads (ADd and ADv), cruralis (CR), gluteus magnus (GL), semitendinosus ventral and dorsal heads (STv and STd), iliofibularis (ILf), iliacus externus (ILe), iliacus internus (ILi), sartorius (SA), tensor fascia latae (TFL), obturator internus (OI), quadratus femoris (QF) and pectineus (Pec). Paths are shown only for proximal hindlimb muscles and represent the path between the pelvis attachment site and the distal muscle attachment site. Individual muscles are marked by the appropriate muscle abbreviations. The top row shows four different views, left to right: ventral, lateral, dorsal, rostral, of hip-flexor-related muscles (CR, GL, ILe, ILf, ILi, SA and TFL). The bottom row shows four different views, left to right: ventral, lateral, dorsal, caudal, of hip-extensor-related muscles (ADd, ADv, GR, SM, STd, STv, OI and QF).