Medial surface of shaft of tibia
Flexes and slightly medially rotates leg; after flexion, extends thigh
Tibial portion of sciatic nerve (L5, S1, S2)
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.