Fig. 2. Representative recordings of muscle-tendon force, fascicle strain and EMG in the plantaris and gastrocnemius muscles of wallaby #2 during (A) level versus (B) incline hopping at 4.2 m s^-1. Whereas gastrocnemius force measured in the Achilles tendon represents the medial gastrocnemius (MG) and lateral gastrocnemius (LG) combined, muscle strain and EMG were recorded from the LG muscle head. Little or no significant differences in force, fascicle strain or neural activation were observed when animals shifted from level to incline hopping at a given speed. The locomotor cycles showing stance and swing phases are those shown in Fig. 4 to describe the in vivo force-length behavior of these muscles.