What does the Soleus muscle primarily do?

The Soleus muscle primarily functions to plantar flex the ankle, particularly when the knee is bent. This muscle is located at the back of the lower leg, underneath the gastrocnemius muscle, and plays a pivotal role in walking, running, and standing. When the knee is flexed, the Soleus is especially effective in pushing the foot down, engaging in activities such as going up on your toes or propelling the body forward during athletic movements. This characteristic makes the Soleus critical for activities that require stable ankle positioning and proper foot mechanics while the knee is in a flexed state, distinguishing its function from other actions such as extending the knee or flexing the hip.