Origin

Ischial tuberosity

Insertion

Medial surface of shaft of tibia

Actions

Flexes and slightly medially rotates leg; after flexion, extends thigh

Nerve

Tibial portion of sciatic nerve (L5, S1, S2)

Note

During walking or running, the hamstrings are used to slow down the leg at the end of its swing and prevent the trunk from flexing at the hip. They are susceptible to being strained by resisting the momentum of these body parts.