The gastrocnemius muscle is the big muscle that makes the bulge at the back of the calf.
The gastrocnemius has two heads.
Knee flexion
The gastrocnemius works in concert with the thigh hamstrings to flex the knee.
-
-
CLINICAL PUBLICATIONS
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.