The Stance
Overall Body Posture
When a bowler lines up in the stance, he or she should adopt an overall posture, which we tern the Athletic pose.  The knees should be bent slightly and the spine inclined forward approximately 15 degrees.
This Athletic Pose is often seen in other sports: a boxer drawing back to deliver a blow; a baseball player preparing to bat; a quarterback throwing a pass.  In this posture, the joints of the body are bent naturally, not stiff and rigid or overly bent. The body is relaxed and comfortable, ready to carry energy forward, leap into action and perform.