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Chin-up bars are playground equipment that were once ubiquitous on children's playgrounds. They are still important in the adult equivalent of a playground, the Par course. A chin-up bar is simply a smooth horizontal metal bar, often a pipe, held solidly above ground by a wooden or metal frame. Typical installations include 2 or 3 different heights of bars for people of different heights. Chin up bars are also a part of a home gym setup.Chin ups can be performed on pull up bars.
In its common usage, a person jumps up slightly to grab the bar in both hands so that the palms are facing away (pronation) and the feet hang freely in the air. The exerciser then pulls himself up to where his chin passes the top of the bar, slowly lowers himself to hanging by his arms, and repeats as many times as possible. This is referred to commonly as a pull-up.
The chin-up is when an inverse grip is used, where the palms of the hands are facing the participant (supination). This type of grip usually places more emphasis on the intercostals and the biceps, whereas the traditional grip is more of an upper-back and latissimus dorsi exercise.
Further variations on chin-ups are possible by gripping with only a few fingers of one hand in order to increase resistance on the other arm. This type of exercise should be balanced evenly on both arms. One-armed chin-ups are also possible but are notoriously difficult to achieve. Training methods for one arm chinups involve exercises that emphasise concentric movements such as Frenchies (pausing during a chin up at the half way and 1/4 and 3/4 way points).
Chin-up bar counts are a part of the U.S. President's Council on Physical Fitness program for evaluating the physical health of schoolchildren.
Types of Chin-Up bars:Doorway, Wall Mounted, Ceiling Mounted, Free Standing
Children found other creative ways to use them, however, such as hanging by the knees, pulling oneself up to the top and sitting on them (more common with monkey bars variation), and so on.