Fig. 1.

Experimental setup for measuring tendon elongation and tendon resting length. Elongation of the tendon was measured as movement of the muscle-tendon junction (MTJ) in reference to the echoabsorptive marker. The resting tendon length was calculated as the distance between the tendon insertion point on the calcaneal bone (A) and ultrasound mid-point (B), adjusted for the distance of the MTJ (C) from the ultrasound mid-point (Tendon Length = LengthAB + LengthBC). GM, gastrocnemius medialis; SOL, soleus.