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Gastrocnemius Muscle (Medial Belly)

Last Updated: Jun 19, 2015

The gastrocnemius muscle or leg triceps is the largest muscle of the back of the calf in the lower leg and the most superficial of the calf muscles. The medial belly of the gastrocnemius muscle is the larger of its two coordinating muscle bundles, originating from the medial head at the femur’s medial condyle as well as connecting to the femur somewhat above the condyle. Distally, it connects withmycontentbreak the posterior calcaneus through the calcaneal tendon (Achilles’ tendon) and via an aponeurosis (a strong, flat tendon) formed by the junction of the two gastrocnemius muscles and the soleus muscle in the lower middle of the calf. Thereby, it draws the heel upward, flexing the foot powerfully to extend the front of the foot and propel the body forward in walking, running, or jumping. The gastrocnemius muscle originates behind the knee (patella), and it performs a lesser role in flexing the leg at the knee joint. The tibial nerve serves and commands the muscle.