MODEL RELEASED. Boxer training on a punch bag. Boxing is a combat sport where two opponents of equal weight hit each other with gloved fists. Punches are only allowed to the head and body. Boxers often aim for a knockout punch that causes the opponent to fall unconscious. Concussion or permanent brain damage can result as a consequence of a knockout punch. Boxers must wear protective equipment such as a gumshield, gloves and, in amateur boxing, head protection.