In violence, martial arts, and combat sports, a kick is an attack using the foot, leg, or knee (also known as a knee strike). This attack is often used in hand-to-hand combat, especially in stand-up fighting. Kicks play a great part in many martial arts, such as Taekwondo, Kung fu, Karate, Kickboxing, Muay Thai, Capoeira, Silat, and Savate. Some arts do not utilize kicks at all, such as judo and boxing. Other arts limit the use of kicks to attacks on the legs and lower body, while some sport martial arts tournaments only allow kicking above the waist. The usefulness of kicks in self-defense and actual combat has been debated. Some, like Bruce Lee, have commented that the leg, thanks to its size and weight, is a more powerful weapon than the arm. Because kicks are more exotic than punches, they may intimidate and catch a fighter off-guard, and because the leg is longer than the arm, kicks tend to keep an opponent at a distance and to sur