What is the agonist muscle in hip flexion?

Rectus femoris+

anterior thigh; quadriceps+

extension of leg at knee

Vastus lateralis+

lateral anterior thigh; quadriceps+

extension of leg at knee

Vastus Medialis+

medial anterior thigh; quadriceps+

extension of leg at knee

Vastus intermedius+

deep anterior thigh; quadriceps+

extension of leg at knee

Sartorius (*)

parallel strap-like muscle that crosses thigh

flexion of knee forward

Biceps femoris*

posterior thigh; hamstring*

flexion of leg at knee

Semitendinosus*

posterior thigh; hamstring*

flexion of leg at knee

Semimembranosus*

posterior thigh; hamstring*

flexion of leg at knee