The Hamstring Muscles

The hamstring muscles at the back of the thigh consist of the biceps femoris, semitendinosus and semimembranosus. See more on how the hamstring muscles are used, and how to strengthen and stretch them.

Semitendinosus

Semitendinosus muscleWhen running the hamstrings act eccentrically to slow down the knee extension motion. Hamstring strains are common in individuals with chronically tight hamstrings or who do not warm-up thoroughly.

Origin : Ischial tuberosity.

Insertion : Upper medial surface of the tibia.

Actions : Hip extension.
Knee flexion.
Internal rotation of the hip when the knee is flexed.

Innervation : Tibial part of the sciatic nerve.

Daily uses : Bending the knee to step over something.

Example strengthening exercises : Knee curl with resistance band.
Nordic curl.

Example stretches : Sitting hamstring stretch.
Standing hamstring stretch.

Semimembranosus

Semimembranosus muscleSemimembranosus is the most medial of the three hamstring muscles. Chronically tight hamstrings are often a contributory factor to lower back pain and knee pain.

Origin : Ischial tuberosity.

Insertion : Posterior part of the medial condyle of the tibia.

Actions : Hip extension.
Knee flexion.
Internal rotation of the hip when the knee is flexed.

Innervation : Tibial part of the sciatic nerve.

Daily uses : Bending the knee to step over something.

Example strengthening exercises : Knee curl with resistance band.
Nordic curl eccentric exercise

Example stretches : Sitting hamstring stretch.
Standing hamstring stretch.

Biceps Femoris

Biceps Femoris muscleBiceps Femoris is one of the three muscles which form the hamstring group forming the back of the thigh. The muscle is often described as having a long head (the attachment from the ischium) and a short head (attached to the femur).

Read more on:

Biceps Femoris Tendinopathy

Biceps femoris tendinopathy, sometimes called biceps femoris tendonitis is inflammation or more likely degeneration of the tendon at the point where it inserts at the outside back of the knee. Here...

Biceps Femoris Tendon Avulsion

A biceps femoris avulsion strain or fracture occurs when the tendon comes away from the bone, taking a small fragment of bone with it causing pain and swelling at the outside back of the knee. It...