Brazilian Jiu Jitsu, contrary to popular misconception, is not a derivative of Jiu Jitsu. It is instead, a derivative of Judo developed in Brazil at the time when the two forms of martial arts were commonly referred to as the other, another common misconception. Fight wear is an important aspect as it says a lot about the fighter’s background.
It is a strategic form of martial arts, as ground fighting and submission moves need thinking through before application. Another common misconception is that weight is an advantage. Throws, grapples, holds, etc are based almost entirely on balance and weight displacement and correct positioning of your body with respect to your opponent. So in a broad perspective, weight does not matter. Even so, in professional fights, opponents are placed in different weight categories to avoid potential issues.
As Brazilian Jiu Jitsu is a respected and age old martial art to the point of it being a tradition, the uniform or gi is normally a must in professional fights and training as well. This gi differs from other judo gis in the sense that it is tighter at the ends. This gives less chance for the opponent to gain an advantage due to a loose end.
Depending on the level, other forms of protection are allowed as well such as a groin protector or chest protector, mouth guard, and head guard. This is mainly to avoid permanent injury resulting in surgery at times.
Guards sometimes restrict a fighter’s movement and judgement, and can get in the way of an invaluable submission move, heard guards especially. Use of the other guards is advocated, but most times a head guard is not allowed. On the upside, such guards prevent unnecessary or unintentional damage that could result in injury that would typically cloud a fighter’s thinking process. It also deters potential under-handed moves that cannot be detected by a referee.
