The triceps surae is a pair of muscle

Muscle

Muscle is a contractile tissue of animals and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...

s located at the calf

Calf (anatomy)

In human anatomy the calf is the back portion of the lower leg . In terms of muscle systems, the calf corresponds to the posterior compartment of the leg. Within the posterior compartment, the two largest muscles are known together as the calf muscle and attach to the heel via the Achilles tendon...

 - the gastrocnemius

Gastrocnemius muscle

In humans, the gastrocnemius muscle is a very powerful superficial pennate muscle that is in the back part of the lower leg. It runs from its two heads just above the knee to the heel, and is involved in standing, walking, running and jumping. Along with the soleus muscle it forms the calf muscle...

 and the soleus

Soleus muscle

- References :* Gray, Henry. Pick, T. Pickering, & Howden, Robert . Gray's Anatomy . New York: Barnes & Noble Books.- External links :...

. These muscles both insert into the calcaneus, the bone of the heel of the human foot, and form the major part of the muscle of the back part of the lower leg, commonly known as the calf muscle.

Origins and insertion

The triceps surae is connected to the foot through the Achilles tendon

Achilles tendon

The Achilles tendon , also known as the calcaneal tendon or the tendo calcaneus, is a tendon of the posterior leg. It serves to attach the plantaris, gastrocnemius and soleus muscles to the calcaneus bone.- Anatomy :The Achilles is the tendonous extension of 3 muscles in the lower leg:...

, and has 3 heads deriving from the 2 major masses of muscle.

• The superficial portion (the gastrocnemius) gives off 2 heads attaching to the base of the femur
  Femur
  The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...
  
   directly above the knee
  Knee
  The knee joint joins the thigh with the leg and consists of two articulations: one between the fibula and tibia, and one between the femur and patella. It is the largest joint in the human body and is very complicated. The knee is a mobile trocho-ginglymus , which permits flexion and extension as...
  
  .
• The deep (profundis) mass of muscle (the soleus) forms the remaining head which attaches to the superior posterior area of the tibia.

The triceps surae is innervated by the tibial nerve

Tibial nerve

The tibial nerve is a branch of the sciatic nerve. The tibial nerve passes through the popliteal fossa to pass below the arch of soleus.In the popliteal fossa the nerve gives off branches to gastrocnemius, popliteus, soleus and plantaris muscles, an articular branch to the knee joint, and a...

, specifically, nerve roots L5–S2.

Function

Contraction of the triceps surae induce plantar flexion

Plantarflexion

Plantarflexion is the movement which increases the approximate 90 degree angle between the front part of the foot and the shin, as when depressing an automobile pedal...

 and stabilization of the ankle complex in the transverse plane. Functional activities include primarily movement in the sagittal plane, stabilization during locomotion (walking, running) and power jumping

Fosbury Flop

The Fosbury Flop is a style used in the athletics event of high jump. It was popularized and perfected by American athlete Dick Fosbury, whose gold medal in the 1968 Summer Olympics brought it to the world's attention...

.

Calf strain (torn calf muscle)

A torn calf muscle happens when the calf muscle is pulled apart from the Achilles tendon. Severe pain is felt by the victim and is often but not always accompanied by a "pop."

This injury happens during acceleration or changes in direction. The torn calf muscle may spasm, and contract forcefully. The toes may also point down (Foot drop

Foot drop

Foot drop is the dropping of the forefoot due to weakness, damage to the peroneal nerve or paralysis of the muscles in the anterior portion of the lower leg. It is usually a symptom of a greater problem, not a disease in itself. It is characterized by the inability or difficulty in moving the ankle...

). Bruises can show up in the leg, foot and ankle due to pooling of blood from internal bleeding. It may take some time for the bruises to occur, from hours to days depending upon where the tear occurred. The circumference of the leg will most certainly increase.

This injury may take several months to heal. It is important not to continue the exercise if muscle is torn, as internal bleeding

Internal bleeding

Internal bleeding is bleeding occurring inside the body. It can be a serious medical emergency depending on where it occurs , and can potentially cause death and cardiac arrest if proper medical treatment is not received quickly....

is taking place. See a doctor immediately after the muscle is torn to begin rehabilitation.