<P> The three muscles of the posterior thigh ( semitendinosus , semimembranosus , biceps femoris long & short head ) flex ( bend ) the knee , while all but the short head of biceps femoris extend ( straighten ) the hip . The three ' true ' hamstrings cross both the hip and the knee joint and are therefore involved in knee flexion and hip extension . The short head of the biceps femoris crosses only one joint ( knee ) and is therefore not involved in hip extension . With its divergent origin and innervation it is sometimes excluded from the ' hamstring ' characterization . </P>
<P> The three muscles of the posterior thigh ( semitendinosus , semimembranosus , biceps femoris long & short head ) flex ( bend ) the knee , while all but the short head of biceps femoris extend ( straighten ) the hip . The three ' true ' hamstrings cross both the hip and the knee joint and are therefore involved in knee flexion and hip extension . The short head of the biceps femoris crosses only one joint ( knee ) and is therefore not involved in hip extension . With its divergent origin and innervation it is sometimes excluded from the ' hamstring ' characterization . </P>
where do the hamstrings originate as a group
where do the hamstrings originate as a group
posterior thigh
posterior thigh