Conformational Balance

The length of a horse's head is a good guide to his overall balance. If a horse is " well balanced" his head will be approximately the same length as the distance from the point of the hock to the ground, or the chestnut on the front leg to the front foot, or the elbow to the fetlock joint, or the depth of his body at the girth, or the point of the stifle to the point of the buttock, or the point of the stifle to the point of the hip.

From the online course Conformation and Selection for Performance

offered by www.horsecoursesonline.com