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.
Quadriceps. The quadriceps as a whole has one main function, and that is to extend the lower leg. However, the rectus femoris also has another function, which is hip flexion. This is because this part of the quadriceps originates at the hip bone, unlike the other quadriceps muscles, which originate at the thigh bone.