The photos show the location of the electrodes. In order:

• Quadriceps femoris muscle (red – vastus lateralis, blue – rectus femoris, yellow – vastus medialis)
• Biceps femoris muscle
• Muscles of the lower leg (red – tibialis anterior, blue – peroneus longus, yellow – peroneus brevis
• Muscles of the lower leg (red – soleus, blue – fibularis longus)
• Gastrocnemius muscle (red – gastrocnemius medialis, blue – gastrocnemius lateralis)