Moving the CG away from the rings, early in frame A, allows gravity to act as an effective motive force and is essential to a well performed stemme forward. A forward motive force on the rings in frame B results in moving the rings outward. Such a maneuver allows for the greatest possible distribution of the gymnast's mass away from the axis of rotation at the rings. A hollow chest technique and the rings placed the greatest possible distance from the CG, produces the desired rotational inertia. Rotational inertia equals the product of the gymnast's mass and mass distribution and is considered to be an important component in angular momentum.
Angular momentum is the product of rotational inertia and angular velocity.
Consequently, maximal rotational inertia created from the early long body technique and gravity's influence on establishing maximal angular velocity on the downswing provide a desirable level of angular momentum at frame D. Anatomical aspects in the downswing phase Anatomical aspects dealing with the downswing phase of the stemme forward are integrally tied to the mechanics of the skill. Blending anatomical and mechanical aspects of human motion can provide the practitioner with information needed to improve performance. Examples of this relationship can be observed in adjusting the angle of muscle insertions to improve the production of torque, securing proper alignment of skeletal structures for manipulating rotational inertia, and producing adequate joint range of motion for maximizing angular momentum created from the force of gravity. Passing through the planche position in frame B is dependent upon proper skeletal alignment and the way in which the lumbar spine, pelvis, and femur interplay. Control of this segment, therefore, is essential for all gymnastics movements.