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Hand position
Varying the width of the grip can alter the mechanics of the movement. The longest range of motion is produced, and the most muscles recruited, when a standard grip is used in which the forearms are vertical at the bottom of the movement. A wider grip shortens the range of motion at the top of the movement, lessening the contribution of the triceps. A narrower grip shortens the range of motion at the bottom, lessening the role of the deltoids and pectorals, as well as placing more emphasis on the triceps. In powerlifting, the legal maximum width a lifter may take on the bar is defined as 81 centimeters between the index fingers. This position is indicated on most barbells by rings.