Semitendinosus

When 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 machine.
  •   Hip extension using a resistance band.

Example stretches

  •   Sitting hamstring stretch.
  •   Standing hamstring stretch.
  •   Partner hamstring stretch.  

Related injuries

  • Hamstring strains.  
  • Hamstring tendinitis.  

Related muscles

  •   Semimembranosus.
  •   Biceps femoris.