U-Kei (martial arts)

U-Kei (U系 or ユーけい, eng. U-Series, U-Group or Class U）is a combat sports related term that refers to either a professional wrestling-, martial arts- and/or mixed martial arts organization, programme or a sportsman with either UWF and/or shootwrestling roots.

The U refers to Japanese professional wrestling promotion UWF, that was active from 1984 to 1986. UWF is credited in pioneer in the "shoot-style" of pro-wrestling and has acted as genesis to modern mixed martial arts, in both Japan and overseas.

During early days of shoot-style pro wrestling in Japan, the professional wrestling and/or mixed martial arts organizations that derived from the idea of UWF are collectively called "UWF-kei", or "U-kei" for short.

List groups, promotions, gyms referred to as U-Kei

 * Shooto
 * Pro Wrestling Fujiwara Gumi
 * Union of Wrestling Forces International - better known as UWF International, U-Inter, or simply UWFi.
 * Fighting Network Rings - trademarked RINGS
 * Pancrase (branched from Professional Wrestling Fujiwara Gumi)
 * Vale Tudo Japan (event organized by Shooto)
 * Battlarts - Fighting Investigation Team Battlarts (格闘探偵団バトラーツ, Kakuto Tantei-dan Batoratsu)(branched from Professional Wrestling Fujiwara Gumi)
 * Kingdom (successor to UWF International)
 * C.A.C.C. Snakepit Japan (formerly U.W.F. Snakepit Japan) (successor to UWF International)
 * U-FILE CAMP (successor to UWF International)
 * ZST (successor to Rings)
 * Real Japan Pro Wrestling (organized by former Shooto founder)
 * Futen Promotion (branching from Battlarts)
 * Gankopuroresu (branching from UWF International and Rings)
 * HARDHIT (organizer is a fighter from Pancrase)
 * Pro-Wrestling Heat-Up Co., Ltd. (branched from UWF International and Rings)
 * GETTO (organizer is a former Shooto fighter)
 * GLEAT (a rebirth of UWF)
 * HOOKnSHOOT (MMA promotion which originally ran Pancrase rules and later became affiliated with Shooto)
 * GLEAT (a rebirth of UWF)
 * HOOKnSHOOT (MMA promotion which originally ran Pancrase rules and later became affiliated with Shooto)