An agonist muscle is a muscle that plays a part in the extension of a muscle. The agonist muscles for a knee extension are the quadriceps and hamstrings.
The quadriceps muscles are primarily involved in knee extension.
The primary function of the knee extension muscle is to straighten the leg by extending the knee joint.
Knee extension is primarily a sagittal plane movement that involves extension of the knee joint, resulting in straightening of the leg. It does not involve any specific type of rotation.
Vertebral Foraminal Entrapment on Hip Flexion and Knee Extension
The antagonists would be those muscles that cause knee flexion. Hamstrings (biceps femoris, semimembranosus, semitendonosis) are the primary knee flexors, and would thus be antagonists to knee extension.
knee extension
Knee extension
Extension. Extension increases an angle, as in straightening a joint. During extension, the knee or elbow are straightened.
quadraceps
iliopsoas
OBTURATOR
Flexion, extension, rotation, adduction of the hip, extension and rotation at the knee