Knickerbocker's theory emphasizes on the interdependence of major players in the same industry. Imitation is the name of the game where firms try to match each other's moves to keep each other in check so as not to allow a rival gain a competitive advantage over others.
hamstrings. extend the hip and flex the knee against resistance and are important knee stabilizers. help control hip flexion in weightbearing position by contracting eccentrically when the flexion occurs in same direction as gravity as dead lift or hip=hinge position.
However, unlike the vastus muscles, the rectus femoris inserts into the hip bone. The lateral femoral circumflex artery and its branches supply the quardriceps with oxygenated blood, and the femoral nerve (and its subsequent branches) innervates the muscle group. The quadriceps assist in extending the knee.