Judo for self defence
There is no complete self-defence and it foolish for a sport or martial art to make such claims. The best self defence is always to avoid a fight, running away if necessary. This may not be what you want to hear but it prevents you mistakenly being charged for GBH. In addition you never know if your opponent is armed or if he has friends ready to join in.
Judo is a sport however self defence skills are an automatic benefit of judo. Judo has it gained prominence as a premier martial art because judo opponents are able to practice frequently at "full bore" against resistive opponents. This can only be achieved if the activity is devoid of high risk inherently dangerous actions. There is a world of difference between "knowing" a technique and actually pulling it off in less than ideal conditions. One can know everything there is to know about hitting tennis balls with racquets but until one actually PLAYS a lot of tennis against committed opponents...
With many street fights being finished with a single punch, the sport of Judo has an obvious drawback in self defence in that it does not include strikes.
Should a street fight not be finished after the first punch, however, it is then common for the two parties to grasp each other. Even boxing champions can on occasion be seen grappling each other, after an initial punch is thrown, when a "weighing in" ceremony gets out of hand.
It is in the standing "grappling" position where Judo comes into its own. For much of your time in Judo you are fighting in this position, in a "live environment", giving it your all and trying to throw your opponent to the floor.
For someone not knowing how to break their fall, being thrown to the floor would be a traumatic experience. Should the fight be taking place on a hard surface (should as tarmac or concrete) then the results of a throw to the floor could be very serious. It is for this reason that "cage fighting", MMA (Mixed Martial Arts) and Judo contests all take place on sprung or padded surfaces.
The use of a sprung floor in cage fighting is in some respects a shame, in that the effectiveness of throws to the ground are lessened, hence such contests concentrate on strikes and submissions. Judo also suffers in cage fighting as the MMA contestants are allowed to fight bare chested. In cold climates like Britain, opponents in a street fight are likely to be wearing a jacket and thus suit Judo techniques far more.
Judo also includes many submission techniques (chokes, strangles and armlocks), though as these take place on the ground, they are not suitable for self defence, as you can never discount a second attacker taking advantage of your being on the floor.
Cage fighting has shown that a mix of martial arts to a high level is probably best for self defence and as such we welcome practitioners from all combat sports. WGC Judo & BJJ Club presently has members with experience of the Brazilian jujitsu, karate, boxing and Thai boxing disciplines.