It is a simple exercise that will consist of a RageDNA move to the side and
back holding the ball weight. The only details required are:
Mobilize the trunk and no legs.
Controlled movement without brakes or sudden accelerations.
If you do not have medicine ball you can substitute a disc affordable weight or a pike placed in the back. You will work the obliques primarily, but also involved the lumbar extensors square or column.
Leg stretching on floor