Barbell

A barbell is a piece of exercise equipment used in weight training, bodybuilding, weightlifting and powerlifting, consisting of a long bar, usually with weights attached at each end.

Barbells range in length from 4 feet (1.2 m) to above 8 feet (2.4 m), although bars longer than 2.2 metres (7.2 ft) are used primarily by powerlifters and are not commonplace. The central portion of the bar varies in diameter from 25 millimetres (0.98 in) to 2 inches (51 mm) (e.g. Apollon's Axle), and is often engraved with a knurled crosshatch pattern to help lifters maintain a solid grip. Weight plates are slid onto the outer portions of the bar to increase or decrease the desired total weight. These weights are often secured with collars to prevent them from sliding off during the exercise, which can result in injuries and death, or flinging the unevenly loaded barbell through the air.

A men's Olympic bar is a metal bar that is 2.2 metres (7.2 ft) long and weighs 20 kilograms (44 lb). The outer ends are 50 millimetres (2.0 in) in diameter, while the grip section is 28 millimetres (1.1 in) in diameter, and 1.31 metres (4.3 ft) in length. The bars have grip marks spaced 910 millimetres (36 in) apart to allow intuitive grip width measurement. It is the standard used in competitive weightlifting where men and women compete at the highest level - the Commonwealth Games, Pan-American Games, World Championships, and the Olympics. Bars of this kind must have suitable "whip" (ability to store elastic energy), sleeves which rotate smoothly, as well as capacity to withstand multiple dropped lifts from overhead.

A women's Olympic bar is similar to the men's bar, but is shorter - 2.01 metres (6.6 ft) - and lighter - 15 kilograms (33 lb) - with a smaller grip section diameter (25 millimetres (0.98 in)). Also in contrast to the men's bar, the women's bar does not sport a center knurl. Powerlifting utilizes the same bar for both male and female competitors.

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