Figure 1. Muscle stiffness was measured using the MyotonPRO device on four muscle sites: (a) rectus femoris (mid-point between anterior superior iliac spine and top of patella), (b) biceps femoris (mid-point between ischial tuberosity and head of fibula), (c) tibialis anterior (one-third from head of fibula to medial malleolus, 2 cm away laterally from tibia), and (d) gastrocnemius (middle of the most prominent muscle bulge when participant tip-toed on one foot).