From Sensei Joe Knight, East Meets West Karate Club of Northern Va.
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Chudan-Zuki (Middle/Chest Punch)

Chudan-Zuki is used extensively in Shorin Ryu Karate. It can be found in all our kata. It is the most practiced technique, and therefore should be our most effective technique. Chudan-Zuki is delivered from low or high stances, and can be delivered with the same foot or as a reverse punch. The target is always the same—the solar plexus of your opponent (the large network of nerves that can be found just below the arch of the rib cage). It is a devastating technique when delivered in conjunction with:

- A strong foundation

- Proper hip rotation

- Ma-ai (the ability to intuitively understand your target distance)

- Corkscrew rotation of the two knuckles as the fist passes through the target

- Straight wrist

- Full extension of the delivering arm

The completed technique should result in a fully extended arm position, with the shoulders square, that is almost parallel with, but slightly pointed towards the deck. Hanshi uses the “drop of oil” analogy- if a bead of oil was placed on the naked shoulder, it would slowly migrate down the arm towards the fist.

Great proficiency can be gained if this technique is continuously practiced on the makiwara. Only the makiwara can give you “instant feedback” if your technique is weak or strong. A deshi whose wrist is bent during kata is a deshi who has not used the makiwara. Hitting the makiwara with a bent wrist does not feel good.... Start slow and lightly with the makiwara and try to synchronize the above attributes into your delivery. Do not get frustrated, just stay at it. Remember to “punch through” the makiwara, not at it.

Chudan-Zuki is a technique that if fully understood and practiced correctly, instantly improves all your kata.