PKClub CrossGym – Rotterdam also offers classes in ‘Mixed Martial Arts’ which is usually abbreviated to MMA, is a multidisciplinary combat sport, which focuses on combining techniques from multiple traditional martial arts. That are collectively referred to by MMA practitioners as TMA (Traditional martial arts), such as grappling, judo, karate, kung fu, kickboxing, thai boxing, boxing, jiu-jitsu, and taekwondo. An important difference with these sources is that the techniques derived from them are separate from all the rules, principles and traditions that are often still characteristic. However, that MMA matches have no rules to protect the fighters is a misconception. Though, these rules differ per organization.