It depends. During stance, mostly the extensors contract: gluteus maximus early on, quadriceps in the
middle, and plantar flexors (soleus and gastrocnemius) toward the end; during swing, instead, the flexors
contract: iliopsoas (for hip), hamstrings (for knee), and tibialis anterior/toe extensors (for ankle).
middle, and plantar flexors (soleus and gastrocnemius) toward the end; during swing, instead, the flexors
contract: iliopsoas (for hip), hamstrings (for knee), and tibialis anterior/toe extensors (for ankle).