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.
Agonist(s) - Gluteus Maximus/Quadriceps FemorisSynergist(s) - Biceps Femoris (Hamstrings)Stabilizer(s) - Transversus AbdominisAntagonist(s) - Hip Flexors (Mainly the Iliopsoas)Movement(s) - Hip Extension/Knee ExtensionPlanes - Sagittal PlaneYour agonist(s) (when done properly i.e. sitting back/knees out) for a squat will be your glutes and quadriceps. Your synergist(s) will actually be your hamstrings as the biceps femorislong head assists greatly in hip extension. Your antagonist(opposing muscle) during a squat will be your Hip flexors i.e. Hip flexion.
prime mover (agonist)
The hamstring and gluteal (buttocks) muscles.
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
yesabduct the thigh
Antagonist: lats Agonist: Abdominals
The iliopsoas muscle is stretched during hip extension. This muscle group is made up of the psoas major, psoas minor, and iliacus muscles. Stretching the iliopsoas can help improve hip flexibility and relieve hip tightness or discomfort.
Flexor carpi
The two functional characteristics used to classify muscles into classes are agonist and antagonist. Agonist muscles are responsible for causing movement, while antagonist muscles work in opposition to the agonist to help control the movement.
in the arm: bicep contracts (agonist) triceps relax (antagonist) in the leg: hamstrings contract (agonist) quadriceps relaxes (antagonist) remember the agonist is the muscle "agonising" to do the work - like pulling the joint.
Agonist - Pectoralis Major, Triceps Brachii Antagonist - Bicep Brachii, Latissimus Dorsi