Dance Anatomy & Kinesiology

168 Dance Anatomy and Kinesiology

Attachments and Primary Actions of Hamstrings

Muscle Proximal attachment(s) Distal attachment(s) Primary action(s)

Hamstrings

Biceps femoris

(BI-seps FEM-o-ris)

Long head: ischial

tuberosity

Short head: linea aspera

of femur

Head of fibula

Lateral tibial condyle

Hip extension

Hip external rotation

(Knee flexion)

(Knee external rotation)

Semitendinosus

(sem-ee-ten-di-NO-sus)

Ischial tuberosity Medial surface of upper

tibia (pes anserinus)

Hip extension

Hip internal rotation

(Knee flexion)

(Knee internal rotation)

Semimembranosus

(sem-ee-mem-brah-NO-sus)

Ischial tuberosity Medial condyle of tibia Hip extension

Hip internal rotation

(Knee flexion)

(Knee internal rotation)

Hamstrings

The hamstring muscle group forms

the bulk of the back of the thigh as

seen in figure 4.8. This group is

composed of three muscles: the

biceps femoris, semitendinosus,

and the deeper semimembranosus.

Their action of extension comes

into play in everyday movements

such as standing, walking, and

controlling forward motion of the

torso. Their function is considered

more postural and fine-tuning in

contrast to the “power” function of

the gluteus maximus. The biceps

femoris (bi, dual + L. capus, head)

appears to be particularly active

with hip extension and is consid-

ered the “workhorse” for hip exten-

sion (Hamill and Knutzen, 1995).

Because each of the hamstrings

inserts distal to the knee, all the

hamstrings act as knee flexors as

well as hip extensors. The medial

hamstrings—semitendinosus (L.

semi, half + tendinosus, tendon)

and semimembranosus (L. semi,

half + membranosus, membrane)—

insert onto the medial part of the

tibia and so can also assist with

knee internal rotation or hip internal rotation when the hip and knee are extended. The lateral ham-

strings (biceps femoris) insert onto the lateral tibia and fibula and so can also assist with knee external

rotation or hip external rotation when the knee and hip are extended.

Palpation: Stand on one leg with your other leg held in a low arabesque position. The hamstrings

can be palpated on the lifted leg at the back of your upper thigh, just below the ischial tuberosity. While

maintaining the leg in this low arabesque position, internally rotate the leg and lift it slightly higher to

the back. The hamstrings and part of the adductor magnus can be felt contracting. Now, place your

FIGURE 4.8 The hamstring muscles (right hip, posterior view). (A) Superficial view,

(B) deeper view.