A knee strike is a strike with the knee, either with the kneecap or the surrounding area. Kneeing is a disallowed practice in many combat sports, especially to the head of a downed opponent. Styles such as kickboxing and several mixed martial arts organizations allow kneeing depending on the positioning of the fighters. Knee strikes are native to the traditional Southeast Asian martial arts and traditional Okinawan martial arts.

Kickboxing is a full-contact hybrid martial art and boxing type based on punching and kicking. Kickboxing originated in the 1950s to 1970s. The fight takes place in a boxing ring, normally with boxing gloves, mouth guards, shorts, and bare feet to favor the use of kicks. Kickboxing is practiced for self-defense, general fitness, or for competition. Some styles of kickboxing include: Full contact karate, Muay Thai, Japanese kickboxing, Lethwei, Sanda, and Savate.