Uneven bars

The uneven bars or asymmetric bars is an artistic gymnastics apparatus. It is used only by female gymnasts. It is made of a steel frame. The bars are made of fiberglass with wood coating, or less commonly wood. The English abbreviation for the event in gymnastics scoring is UB or AB, and the apparatus and event are often referred to simply as "bars". The bars are placed at different heights and widths, allowing the gymnast to jump from bar to bar.

Uneven bars used in international gymnastics competitions has to conform to the guidelines and specifications set forth by the International Gymnastics Federation Apparatus Norms brochure. Several companies manufacture and sell bars, including AAI (USA), Jannsen and Fritsen (Europe) and Acromat (Australia).

Gymnasts will often use a single bar to practice skills on the bar, mostly for safety and for ease of spotting. Many gyms also have a single bar or a set of uneven bars over a loose foam pit for learning new skills to provide an additional level of safety.

Measurements of the bars are provided by the Fédération Internationale de Gymnastique (FIG) in the Apparatus Norms brochure.

Routines usually include a lot spinning, jumping and swings

The uneven bars apparatus originally consisted of men's parallel bars set to different heights. Consequently, the bars were very close together, and gymnasts could transition from one to the other with little difficulty. Routines of the early 1950s chiefly consisted of simple circles, kips, and static balance elements and holds. In the late 1950s the trend shifted toward fluid motion, and gymnasts began to perform routines composed of more difficult circles, kips, beats (bouncing the body off the low bar while hanging from the high bar), wraps (wrapping the body around the low bar while hanging from the high bar) and transitions. Release moves also began to come into play, although they were almost entirely limited to transitions between the low and high bars. In the late 1960s/early 1970s, companies began manufacturing uneven bars as a separate specific apparatus. The design was changed slightly to allow the bars to be adjustable, with tension cables that held the apparatus to the floor. As a result of this change, coaches could set the bars farther apart. Additionally, the circumference of the bars themselves decreased, allowing gymnasts to grasp and swing from them with greater ease.

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