For yoga ball ,the regular diameter is 20cm, 55 cm,65cm,75cm.
You can choose yoga ball size based on your weight and height. On the market are blue, red, gray and so on, according to the individual color preferences.Men should choose a little larger, women should choose slightly smaller. If it is a petite woman, Choose 45 cm or 55 cm yoga ball, while 65 cm and 75 cm yoga ball is more suitable for tall men.
In addition to the size of the choice of more important is to choose from the regular manufacturers of durable fitness balls, to be very elastic and full of security. Yoga ball can bear the weight of the average person, because we don't put all the weight on the ball when we exercise. It just carries part of the weight, and our body has a counterproductive force against the ball, and the fitness ball lets us relax and sink, and our body also has a force of its own up. And tighten the muscles around the bones to protect our bodies.