which is fixed by nature to each man, just like blood types
The stance of these four types, will differ in the way they stand, sit, walk, and grab.
These four types can be divided into where to put the center of gravity at feet.
A2 type: outside of the toe, (hand) ring finger
B1 type: the inside of the heel, (hand) index finger
B2 type: outside of heel, (hand) ring finger
Type A1, B2 type is "cross-type".
While running left hip and right shoulder, and the right hip and left shoulder the axis of the body move diagonally. Twist motion
whereas
A2 type, B1 type is "parallel type", the axis of the body is parallel.
This is very very important factor for sport.
It affects the way you throw, hit, kick, jump, running and etc