In our country, some people exercise their fingers with wooden balls, stone balls and walnut balls for a long time. Later, some rich and powerful nobles developed them into glass balls and jade balls, and gradually evolved into solid iron balls. These balls with different materials and playing with fingers gradually formed the early fitness balls in China.

Baoding Shoubao Fitness Ball, also known as Baoding Iron Ball, has a diameter of 4-5.5 cm and a weight of 200 -500 g. The ball is round and shiny, with a ball inside and a soundboard. Two of them are a pair, which can make a crisp and pleasant sound, and are called "male and female" balls.