Resistance training is a general term used to describe exercises that cause the muscles to contract against an external resistance. The expectations of a resistance-training program can include positive alterations in body composition including muscle hypertrophy, increases in maximum strength, power, and endurance. Instruments/devices supplying the external resistance can include body mass, elastic bands, bricks, bottles of water, and typically barbells and dumbbells. Weightlifting is a competitive sport in which the athletes use barbells in competition to perform 2 competitive lifts, the snatch and the clean and jerk. In training, weightlifters may use both dumbbells and barbells as well as a variety of benches and racks. Weightlifting is governed internationally by the International Weightlifting Federation.