Muscle Groups of the Upper Arm: Biceps and Triceps Brachii

Functions and Biomechanics of the Biceps Brachii

The upper arm is primarily composed of two major muscle groups: the biceps brachii and triceps brachii. These muscles play a crucial role in arm movements, including flexion, extension, and stabilization of the elbow and shoulder joints.

Overview of Biceps Brachii

The biceps brachii consists of two heads—the long head and short head—originating from the scapula and inserting into the radius. It is responsible for flexion of the elbow, supination of the forearm, and contributing to shoulder stability.

Biomechanics of Biceps Brachii

• Flexion: The primary function is elbow flexion, allowing movements such as lifting objects.
• Supination: The biceps play a key role in forearm supination, rotating the palm upward.
• Shoulder Stabilization: The long head assists in maintaining stability and movement of the shoulder joint.

Overview of Triceps Brachii

The triceps brachii, located at the back of the upper arm, consists of three heads—long, lateral, and medial. Its primary role is elbow extension.

Functions of Triceps Brachii

• Elbow Extension: Enables straightening of the arm.
• Shoulder Support: The long head contributes to shoulder joint stability.

Conclusion

Understanding the biomechanics of the biceps and triceps brachii is essential for athletes, medical professionals, and individuals undergoing rehabilitation. Strengthening these muscles enhances mobility, stability, and overall arm functionality.