The gastrocnemius muscle is the big muscle that makes the bulge at the back of the calf.

gastrocnemius muscle
The gastrocnemius has two heads.


Knee flexion

The gastrocnemius works in concert with the thigh hamstrings to flex the knee.


Knee muscles from the back

A brief overview of the knee muscles at the back of the knee.



Gastrocnemius vs. soleus strain: how to differentiate and deal with calf muscle injuries. Dixon JB. Curr Rev Musculoskelet Med. 2009 Jun; 2(2): 74–77.

See also -