The gastrocnemius is a large muscle located in the lower leg forming part of the calf. Its purpose is to push the leg down when required during activities such as walking, jogging or even just standing. The soleus is the other major muscle of the calf and together with the gastrocnemius is important for both flexing the ankle and knee. A torn calf may involve the gastrocnemius muscle, soleus or both although treatment is similar for all three situations.

The gastrocnemius originates toward the bottom of the femur and inserts at the Achilles tendon. Sometimes the gastrocnemius muscle is considered to be the same as the soleus as they have the same insertion point and work closely together. Both the soleus and the gastrocnemius allow plantar flexion of the foot, which is important in a number of different activities.

As a whole, the calf muscles are involved in any action that includes plantar flexion of the foot or flexion of the knee. This includes standing on tip toes, walking and running. The only difference between the soleus and gastrocnemius muscle when it comes to movement is that the soleus is more active when the knee is bent. In contrast, the gastrocnemius muscle is under most tension when the knee is straight.

The gastrocnemius muscle also has two heads. This means it attaches on both sides of the knee to provide stability. Medically, this is described as the muscle having both a medial and lateral attachment to the knee. The gastrocnemius actually takes on a diamond-like shape when viewed from behind as long as the muscle has fully developed.

There are a number of different injuries that could affect the gastrocnemius. One of the most severe is a muscle tear that can render the person unable to stand correctly until healed. Other injuries include inflammation due to repetitive strains and chronic tightness. Treatment for these injuries depends on the severity of the condition and the exact location of the injury.

Symptoms of a gastrocnemius tear vary depending on severity. Grade 1 tears are characterized by a small amount of pain and tightness in the muscle. This usually becomes more apparent a few days after the initial injury. A Grade 1 tear often won’t prevent an athlete from competing although rest may be required for a full recovery. Grade 2 and 3 tears are more severe and may require more extensive treatment, including surgery.