Fig. 2. Representative fascicle length and EMG for the ILPO (A) and the FT (B) for one individual running at 2 m s^–1 on the level. Shaded areas represent stance. Muscle lengths are presented as a fraction of L_o, calculated as the average muscle length over a stride. Broken lines on the third stride indicate the period of stance lengthening (L) and shortening (S) for which all measurements in this study were taken.