Question

What is the agonist and antagonist of shoulder flexion?

Answer 1

In shoulder flexion, the agonist muscle is the anterior deltoid, while the antagonist muscle is the posterior deltoid. The anterior deltoid contracts to lift the arm forward, while the posterior deltoid relaxes to allow this movement.

Answer 2

The anterior deltoid is the agonist for shoulder flexion, assisted by the pectoralis major and biceps brachii, while the latissimus dorsi and posterior deltoid serve as antagonists.

Step-by-step explanation:

The agonist in shoulder flexion is primarily the anterior deltoid, assisted by the pectoralis major and biceps brachii. When only the anterior fascicle of the deltoid is stimulated, the arm will both abduct and flex at the shoulder joint. The antagonist muscles, which oppose shoulder flexion, include the latissimus dorsi and posterior deltoid. These muscles extend the shoulder and act in opposition to the anterior deltoid during shoulder flexion movements.