Conditioning for many of the hand strikes of kung fu -- iron fist training -- involves striking progressively heavier and harder surfaces. Starting small, with a bag of dried peas, you drive your hands repeatedly into the bag until your conditioning improves. This increases the durability of the striking surfaces of your hands, and it builds strength in your wrists. Buckets of sand for open hand strikes develop durability in your fingers. Consult a health care practitioner before beginning any martial art or exercise program.
Building a fist of iron begins with vegetables. A small canvas bag filled with dried peas forms a solid, yet somewhat forgiving striking surface. Attach this bag to a firm surface that will not move, such as a wall or tree. Ensure that the bag is sturdy, held together with heavy thread and reinforced seams. Otherwise you will spend more time picking up peas that you will spend hitting them. Affix the bag, which should roughly be 12 inches square and flat, to the wall roughly level with the center of your chest.
Close your fist properly to avoid damage to your hand or wrist. Roll your fingers in first, and ensure that your thumb is on the outside of your fingers, covering the first one or two. Keep the back of your hand in line with your forearm, and clench your fist tightly. When punching the bag, at first jab lightly until you become accustomed to hitting it, then add power from your torso, then your legs. Strike with the first two knuckles of your fist.
Start by hitting the bag every other day, and gradually work up to daily striking sessions. When you can consistently hit the peas on a daily basis without pain, replace the peas with ball bearings roughly the same size as the peas. Then move up to pea gravel.
Closed Fist Techniques
Kung fu features a variety of hand-striking techniques, including the back fist and hammer-fist. To strike with the back fist, turn so that your back is to the wall and you are at one side of the bag. Strike the bag with the the first two knuckles of your fist in a manner similar to delivering a backhand slap. Turn your hand over and strike with the bottom, or soft part of your clenched fist to do the hammer-fist technique. Train your hammer fist in the same manner.
Conditioning for open hand techniques is part of iron fist training. A knife edge strike is delivered with the outside edge of your hand in a manner similar to the back fist. Open your hand, stiffen your fingers, and strike the bag solidly with the edge of your hand. Spear-finger techniques, delivered with the fingers extended and held tightly together, target soft spots on your opponent. Begin conditioning for this by driving your fingers into a bucket of dried peas in the same manner you trained your close fist. Work up to ball bearings, pea gravel then finally a bucket of loose sand. Conditioning the spear finger technique is a long and sometimes painful process.