直径55MM如下图：

 直径45MM如下图：

Instructions:
The first method: the ball

1. Five fingers grip the ball: fingers naturally seize a ball separately, each finger force the ball, pause after a relaxation. Requirements: The power of holding a slow and long-lasting, pause when your fingers have soreness and then relax, so a pinch and a loose, repeated the ball 6-10 times.
2. Tiger mouth ball: four fingers close together, separated from the thumb, a ball in the hands of the tiger's mouth, rhythm, force the ball, a folder of a pine. Note: forced to squeeze the ball, the hand of the tiger mouth should have a sense of tension, repeated ball 6-10 times.
3. Palm grip the ball: a ball on the palm of your hand, the fingers of the natural grasp of the ball on the ball, and then grip the ball hard moment, and then relax for once. Requirements: hard grip the ball a moment, to be sore hand feeling, to relax, grip the ball repeatedly 8-12 times.
4. hands rubbing the ball: palms relative hands, the ball in the palm of the hand, a single direction of the practice of racket; you can also hands five fingers intersect, squeeze the ball with each other with the palm of your hand. Requirements: hands rubbing the ball up and down hard, rub clockwise, then anticlockwise rub, otherwise it can be. Times and hours are not limited.
The second method: one hand care two goals, turn around alternately.
The two balls in the palm of your hand, by flexion and extension of the order of five fingers to circling the ball around each other, the direction of rotation has cis, inverse points, all the joints in the hand are in motion. With the fingers flexion and extension, the forearm muscles can rhythmic contraction and relaxation. Primary training optional small model, to be skilled, and gradually buy a larger model. Alternate exercise with both hands, but also three or four ball rotation while playing several tricks. Specific can be divided into the following 5 kinds.
(1) single-handed double-ball friction rotation. Set a double ball in the palm of a single hand, finger force, so that the ball in the palm of your hand and reversed. Keep your fingers in close contact with the ball while rotating so that the balls rub against each other without colliding. Double ball in the palm of your hand, finger forced the ball, so that the ball in the palm of your hand clockwise or counterclockwise rotation. Requirements: clockwise rotation, the ball through the thumb, little finger in turn to the index finger; counterclockwise rotation, the ball to go through the thumb, index finger, middle finger, ring finger and little finger.
(2) hands and four-ball exercise. This is a one-hand exercise, based on the gradual exercise of both hands while doing one-handed action (each ball), need to give full play to the role of the brain can be done. This action is difficult, requiring high technology, but the effect is better than one-hand exercise.
(3) massage with an iron ball, rub, hit parts of the body discomfort
(4) with one hand or both hands hard to hold the tiger's mouth, or hold the ball with the palm of the hand hard, hot and sour feeling, often such exercise to improve finger strength, wrist strength, grip strength, arm strength are helpful.
 Maintenance:
To prevent moisture, keep clean and dry, to avoid violent impact.