The primary knee extension muscles are the quadriceps muscles, which include the rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius. These muscles work together to straighten the knee joint by contracting and pulling on the patellar tendon, which in turn moves the lower leg forward and extends the knee.
The primary muscles involved in hip extension are the gluteus maximus and the hamstrings. The primary muscles involved in knee flexion are the hamstrings and the gastrocnemius.
Teo
The supinator muscle is a muscle in the forearm that is not directly responsible for flexion or extension of the arm. Its primary function is to rotate the forearm in a movement called supination, where the palm faces up.
Agonists
Agonists
The biceps femoris is one of the hamstring muscles located at the back of the thigh, and its primary function is to flex the knee and extend the hip. During knee extension, the quadriceps muscles contract to straighten the leg, while the biceps femoris must relax to allow this movement to occur. Hence, it acts as an antagonist to the quadriceps during knee extension, opposing their action and facilitating smooth movement.
The primary muscles responsible for movement and stability in the arm from the elbow to the wrist are the flexor and extensor muscles. These muscles allow for bending and straightening of the arm, as well as controlling movements of the wrist and fingers.
The primary scapular depression muscles are the lower trapezius, latissimus dorsi, and pectoralis minor. These muscles work together to stabilize the shoulder by pulling the scapula downward and inward towards the spine. This action helps to maintain proper alignment of the shoulder joint during movement, reducing the risk of injury and allowing for smooth and controlled shoulder movements.
Agonist muscles are the primary muscles responsible for producing movement. However, synergist muscles are helper muscles that assist the agonist in executing a particular movement. Synergists help stabilize the movement and control the direction in which the force is exerted.
The primary muscle groups targeted during back extension exercises are the erector spinae muscles, which run along the spine and help with back stability and posture.
The primary actions of muscles in the hip joint include flexion (e.g., iliopsoas), extension (e.g., gluteus maximus), abduction (e.g., gluteus medius), adduction (e.g., adductor muscles), internal rotation (e.g., tensor fasciae latae), and external rotation (e.g., piriformis). These muscles work together to provide stability and movement in the hip joint during activities like walking, running, and squatting.
muscular system