premise: Brazilian jiu-jitsu prohibits grappling.
hypothesis: Brazilian Jiu-Jitsu ( [ dʒuːˈdʒɪtsuː ] [ ˈʒiw ˈʒitsu ] , [ ˈʒu ˈʒitsu ] , [ dʒiˈu dʒiˈtsu ] ) ( BJJ ; jiu-jitsu brasileiro ) is a martial art , combat sport system that focuses on grappling and especially ground fighting . BJJ promotes the concept that a smaller , weaker person can successfully defend against a bigger , stronger , heavier assailant by using proper technique , leverage , and most notably , taking the fight to the ground , and then applying joint-locks and chokeholds to defeat the opponent . BJJ training can be used for sport grappling tournaments and in self-defense situations .