What muscle are you using when hit a nail with hammer?

The main muscle used when hitting a nail with a hammer is the triceps brachii. This muscle is located on the back of the upper arm and is responsible for extending the elbow joint. When you swing the hammer, the triceps contracts to straighten your arm and drive the hammer head into the nail.

Additional muscles used in this动作包括:

* Deltoid: The deltoid muscle is located on the shoulder and is responsible for raising the arm and providing stability to the shoulder joint.

* Trapezius: The trapezius muscle is located in the upper back and is responsible for moving the neck, shoulders, and upper back.

* Flexor carpi radialis: The flexor carpi radialis muscle is located on the forearm and is responsible for flexing the wrist.

* Extensor carpi radialis: The extensor carpi radialis muscle is located on the forearm and is responsible for extending the wrist.

These muscles work together to coordinate the movement of the arm, shoulder, and wrist, allowing you to drive the nail into the surface.