Chin-up

The chin-up (also known as a chin or chinup) is a strength training exercise. People frequently do this exercise with the intention of strengthening muscles such as the latissimus dorsi and biceps, which extend the shoulder and flex the elbow, respectively.

It is a form of pull-up in which the range of motion is established in relation to a person's chin.

In the 1970s and 1980s, the term chin-up not only included an overhand/pronated ("palms away") grip, but some authors used it as the default meaning of the term, with an underhand/supinated ("palms toward") grip called a "reverse" grip. Even in the 2010s "chin-up" still includes palms-away lifting. The term "chin-up" is still regularly used refer to pulling using an overhand-grip.

Both pull-ups and chin-ups are two of the best exercises for back and overall upper body conditioning. However, they target the muscles a bit differently. Both exercises will work the latissimus dorsi and biceps, but standard chin-ups—with an underhand grip—place more emphasis on the biceps.

A chin-up is named by bringing the chin up through space, specifically in relation to its position with the bar or other hand grips. This can be either touching the bar (more easily done by extending the neck, though that could be considered cheating) or by bringing the chin over the bar. This exercise is easier for males than females because of the male tendency to have stronger and larger biceps.

This is usually achieved most easily with vertical forearms that are close to the body. For most, bringing the chin this high is most easily achieved with a supinated (underhanded, palms-toward) grip. Due to this, the phrase "chin-up" has become associated with pulling with this type of grip. Some have delegated the term pull-up to refer to the pronated (overhanded, palms-away) grip. In spite of this, many refer to pull-ups with a pronated grip also as chin-ups, and the supine grip is still regularly called a pull-up.

Some organizations such as the American Council on Exercise have adopted this new terminology, issuing statements such as: "a chin-up differs from a pull-up in that the puller's hands are facing towards him or her in a chin-up, and away in a pull-up." Organizations such as the United States Marine Corps, however, use the term pull-up interchangeably to refer to both the overhand and underhand grips.

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