Four limbs are better than two.
In Brazilan jiu-jitsu (BJJ), one of the distinguishing characteristics of the ‘little guy jiu-jitsu’ used by smaller BJJ practitioners is that smaller folks in BJJ tend to use their legs a lot more for manipulations, attacks, and defenses than larger practitioners do. In my observation and experience, a larger jiu-jitsu practitioner is more likely to use his or her upper body to pin, attack, or defend while rolling. Smaller practitioners, on the other hand, rely on their legs much more to make space, apply leverage, and secure positions. In this way, the legs become a sort of force multiplier, not only compensating for whatever size or strength the smaller practitioner may be lacking, but also making his or her entire body a threat to his or her opponent.
While the arms and hands tend to have more dexterity than the legs and feet, the lower limbs tend to be stronger. With specialized training exercises and lots of repetitive drilling, however, the legs can gain dexterity, making them even more of a threat because of their already natural strength. A practitioner especially skilled with his or her legs can and will use them as or more effectively than many practitioners use their arms and hands. All other things being equal, this essentially makes smaller folks twice as threatening as practitioners who rely on their upper body to do most of the work. What’s more, by using the legs to manipulate or tie up an opponent, the arms are then free to attack in ways they may otherwise not be able to if they were doing the work that the legs now do. This creates freedom. WIth freedom comes opportunity. With opportunity comes creativity and with creativity comes fun.
-Robert Van Valkenburgh teaches Taikyoku Budo and Brazilian Jiu-Jitsu at Kogen Dojo