Which muscle flexes the elbow?

Which muscle flexes the elbow?

• A. Brachialis
• B. Biceps Brachii
• C. Triceps Brachii
• D. Deltoid

Answer: (A)

Elbow flexion is produced by muscles that cross the elbow joint and shorten to bring the forearm toward the upper arm. The brachialis sits directly on the front of the elbow, attaching from the humerus to the ulna. When it contracts, it pulls the ulna and bends the elbow with a strong, straightforward action, making it the most effective elbow flexor across different forearm positions. The biceps brachii also helps flex the elbow, but its main strength lies in forearm supination and shoulder-related actions, so its role at the elbow is supportive rather than primary. The triceps brachii does the opposite, extending the elbow. The deltoid acts on the shoulder, not the elbow.

Elbow flexion is produced by muscles that cross the elbow joint and shorten to bring the forearm toward the upper arm. The brachialis sits directly on the front of the elbow, attaching from the humerus to the ulna. When it contracts, it pulls the ulna and bends the elbow with a strong, straightforward action, making it the most effective elbow flexor across different forearm positions.

The biceps brachii also helps flex the elbow, but its main strength lies in forearm supination and shoulder-related actions, so its role at the elbow is supportive rather than primary. The triceps brachii does the opposite, extending the elbow. The deltoid acts on the shoulder, not the elbow.