The Fourth Principle of kata analysis...in no particular order

"Since Goju-ryu is a system of self-defense...it should seem effortless."

Even though you train to be stronger, faster, more flexible, or just plain tougher, self-defense techniques, or a self-defense system, should require little of this to work. You should put the effort into developing your strength and speed and flexibility when you are young; otherwise, you won't have much of anything when you are older it is sometimes said, but the techniques themselves shouldn't depend on strength or speed to work. In the first place, there will always be someone bigger or stronger or faster. But more importantly, your self-defense should work for you when you are old, when you may be least able to defend yourself.

Twisting the head in
Seipai kata.

Knee attack to the head
in Saifa kata.

Instead, Goju-ryu relies on technique, and that technique is based on principles of movement. This is what makes it seem effortless. For instance, we step off-line to "block," and most of these off-line movements may be accompanied by a spinal rotation in the trunk or core of the body. The receiving techniques ("uke") of Goju-ryu are, for the most part, "soft" because they can be, generally meeting the opponent's attack with circular "blocks" that deflect the attack. In addition, the position of the arms first encountered in Sanchin training is applied, in principle, to many of the receiving techniques in Goju, and when this "immovable arm" is used in conjunction with stepping off line and the rotation of the trunk, any effort or energy the defender uses can be saved for the counter-attack; though these counters can be just as effortless if the same understanding of stepping and rotation is used there as well.



Shoulder attack
to head in Seisan.

Lastly, so many of the techniques of Goju-ryu are effortless because Goju-ryu attacks vulnerable parts of the body. The finishing techniques of Goju are against the opponent's head or neck, either striking the neck with the fingers, the knife-edge, or the forearm, or grabbing the head and chin and twisting, as in Suparinpei. Or we attack the head with the elbow, as in Seiunchin. Sometimes the knee is used to attack the head, as in Saifa and Kururunfa, and sometimes even the shoulder is used, as in Seisan kata. 

Whatever the case, it should be effortless. And it is usually effortless because we have moved in such a way that the opponent is not given a second opportunity to attack, our first block/attack is often simultaneous, and we bridge the distance to attack the head or neck.

Relax, relax, relax...you'll be faster and stronger.