Since boxing involves forceful, repetitive punching, precautions must be taken to prevent damage to bones in the hand. Most trainers do not allow boxers to train and spar without wrist wraps and boxing gloves. Hand wraps are used to secure the bones in the hand, and the gloves are used to protect the hands from blunt injury, allowing boxers to throw punches with more force than if they did not utilize them. Gloves have been required in competition since the late nineteenth century, though modern boxing gloves are much heavier than those worn by early twentieth-century fighters. Prior to a bout, both boxers agree upon the weight of gloves to be used in the bout, with the understanding that lighter gloves allow heavy punchers to inflict more damage. The brand of gloves can also affect the impact of punches, so this too is usually stipulated before a bout. A mouth guard is important to protect the teeth and gums from injury, and to cushion the jaw, resulting in a decreased chance of knockout.
Boxers practice their skills on two basic types of punching bags. A small, tear-drop-shaped "speed bag" is used to hone reflexes and repetitive punching skills, while a large cylindrical "heavy bag" filled with sand, a synthetic substitute, or water is used to practice power punching and body blows. In addition to these distinctive pieces of equipment, boxers also utilize sport-nonspecific training equipment to build strength, speed, agility, and stamina. Common training equipment includes free weights, rowing machines, jump rope, and medicine balls.