Which Muscle Group Is An Antagonist To Knee Extension?

Which Muscle Group Is An Antagonist To Knee Extension? The hamstrings are the agonist and the quadriceps are the antagonist. In the contact and recovery phase, the quadriceps contract to extend the knee while the hamstrings lengthen to allow the movement. The quadriceps are the agonist and the hamstrings are now the antagonist. What muscles