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
There is no advantage or disadvantage in these types. This is why there are many athletes have different style, but can be successful in professional.
Therefore knowing this type can change your style and can find the best form that really suits you
how to find your type
Squat
A1 and A2 Need to bent forward first to squat = toe balanced
B1 and B2 Can drop the hip and chest vertically = heel balanced
how you grab a cup
A1
Pinch around the fingertips of the index finger, middle finger, thumb
A2
Pinch around the fingertips of ring finger, middle finger, thumb
B1
Wrap around the base of the index finger, middle finger, thumb
B2
Wrap around the base of the ring finger, middle finger, thumb