During this early time, kickboxing and full contact karate are essentially the same sport.
The rules ranged from Semi-Contact which was similar to many Karate competitions where the purpose is to score points with an emphasis on delivery, speed and technique, to Full-Contact which was essentially a mixture of Western Boxing, Karate & Taekwondo skills. The males fight bare chested with kickboxing trousers, gloves, shin guards, groin guards and mouth guards (headgear for amateurs or children under 16). Full contact rules had a general range consisting of just punches and high kicks, then low kicks could be allowed, eventually building up to allowing sweeps, knees and elbows. Females could wear sports bra's and chest gear.
The institutional separation of American full-contact Karate from Kickboxing occurred with the formation of the Professional Karate Association (PKA) in 1974 and of the World Kickboxing Association (WKA) in 1976. They were the first organised body of martial arts on a global scale to sanction fights, create ranking systems, and institute a development programme.
The PKA went into financial decline in the mid 1980's and as a response to these legal and revenue issues, the International Sport Kickboxing Association (ISKA) was formed.
ISKA along with the International Kickboxing Federation (IKF) has continued to thrive into the modern era.
Notable Kickboxers who popularised Kickboxing from the USA are: