Both powerlifting and weightlifting require a barbell for training and competition. These barbells differ slightly in composition and flexibility. Both sports have specialized bars for special purposes. Both sports use bars with sharp knurling -- the diamond pattern that helps maintain a proper grip -- and smoothly rotating sleeves on the ends of the bars. A good bar makes a difficult lift slightly less painful, or at least puts you at less risk of dropping it.
Weightlifting bars weigh 20 kilograms for men and 15 kilograms for women, as per International Weightlifting Federation rules. The bar is smooth in the center, but has a diamond shaped knurling pattern extending inward from the collars for 40 cm on each side. The smooth center means the bar will not scrape you when you rack the clean, or catch the bar on your shoulders. The women's bar, in addition to being lighter, is 3 cm narrower than the men's bar.
Specialty Weightlifting Bars
Smaller bars exist to train children and those who lack physical strength and dexterity. Some bars weigh only 10 kilograms, or 22 pounds. A special bar weighing only five kilograms, or just over 11 pounds, is also available. All bars feature sharp knurling to maintain a proper grip during the snatch and clean, and all feature smoothly rotating sleeves. All weightlifting bars require that you load plates on them to add weight. There are no fixed-weight weightlifting bars.
Powerlifting bars started out based on the weightlifting bar, but many training bars use the English standard system of measure and weigh in at 45 pounds. This goes with American powerlifting sets that feature weights in pounds. In international competition, the metric system is used and a 25 kilogram bar remains the standard. Powerlifting bars all feature knurling in the center, to help the bar bite into your upper back when squatting, as well as knurling to help your grip when deadlifting. Powerlifting bars are less flexible than weightlifting bars, despite weighing the same.
Special Powerlifting Bars
Powerlifting also features special bars, such as the Texas power bar, which is stiffer and even less flexibility than a standard bar. This allows you to walk out of the squat rack with better control of the weights. A special deadlifting bar is also available, and this bar is slightly thinner and more flexible, making a heavy deadlift easier to hang onto. Lighter training bars in a variety of sizes also exist.