Also called Kigu Undo.

Hojo Undo consists of both one and two-person training with various traditional weight-training and striking implements.

Makiwara
This punching board is the foundation of Okinawan Karate, and one of the training devices unique to karate.  This tapered board provides enough resistance to properly train the Okinawan-style punch, but is springy enough to allow the karateka the ability to train without damaging the body.

Chi-Ishi
This weighted stick is used to primarily to strengthen both the grip and the wrist.  A strong wrist is necessary for proper striking and blocking, and a strong grip is essential for the close-quarter grabbing and locking techniques of Goju-Ryu.

Nigiri-Game / Sanchin-Game
These weighted pots are used to train the grip strength of the karateka while the student practices lower-body movement techniques.  In addition, the weight helps to remind the student of the importance of keeping the shoulder down.

Ishi-Sashi
Much like the Chi-ishi, the Stone Padlocks help to train both the student's grip and wrist strength.  With many grabbing and locking techniques in the Goju-Ryu kata, it is vital that the student build the strength necessary to apply them.

Tetsu-Geta
Practice of various kicking techniques while wearing the Iron Sandals will train both the karateka's balance and hip strength.

Kongo-ken
The concept of using a huge link of anchor chain was brought back to Okinawa by Miyagi Chojun who saw it being used in Hawaii by wrestlers who tossed it around, practicing throws and using their entire bodies to move the heavy iron object.

Tan
This barbell-like device, in Okinawa was often composed of the wheels of a small train car, joined by a wooden axle.  This tool is not used by simply lifting repeatedly, instead, it is used primarily as a conditioning tool for the arms.

Note: Many of the training devices here, for example the Chi-Ishi, Nigiri-Game, Ishi-Sashi, and Tan, have direct counterparts in many Southern Chinese martial arts.