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In Depth: Muscles

Toned and muscular arms are often seen as a sign of physical fitness, so many people spend ample time in the gym trying to sculpt perfect-looking muscles.

The major exterior muscles of the arm yield the arm’s curved shape on the inside and outside. These bulky muscles also give the arm its strength as they contract or expand with arm movements.

The muscles of the arm that can be seen easily on the surface include:

  • Bicep: A large muscle of the upper arm, a flexed bicep is often viewed as a sign of a person’s strength. Formally known as the biceps brachii muscle, the bicep rests on top of the humerus bone. It rotates the forearm as well as flexes the elbow.
  • Tricep: This large muscle in the back of the upper arm helps straighten the arm. It is formally known as the triceps brachii muscle.
  • Brachioradialis: This muscle, located at the top of the forearm near the elbow, helps rotate the forearm both outwardly and inwardly. Because of this type of movement, it is sometimes known as the “beer drinker muscle.”
  • Extensor carpi radialis longus: This muscle next to the brachioradialis is one of five major muscles that help move the wrist. When you clench your fist, this muscle bulges out from the skin.
  • Deltoid: Although technically part of the shoulder, the deltoid muscle controls the majority of the shoulder’s movement and thus gives the arm more range of motion.

Strength training exercises are common ways to increase the size and overall strength of the major muscles in the arms. Common exercises to build up arm muscles include curls, presses, pushdowns, and extensions using weights.

Pain can occur anywhere in the arm. The most common cause of arm pain is overexertion of a muscle or injury to it. Twisting, pulling, or falling are common ways muscles in the arms become painful. Although repetitive injuries affect the deep muscles more often, pulled muscles from lifting something too heavy or overexerting can also create pain and soreness, but this usually subsides in a few days.

Arm muscle pain can usually be easily treated with resting the affected muscle and icing, elevating, and compressing the area. 

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