Exercise is a process, not a program, of stimulation and response/adaptation. It is the body challenged appropriately—an internal tug of war between muscles and resistance around bones and joints, which stimulate a muscular response. The exercise must have a specific joint position, but not necessarily a motion, depending on the goal. There must be a specific resistance, a specific time/duration, a specific effort/exertion, and a specific goal/intention.
As a Resistance Training Specialist, I’ve come to understand that there are no rules of exercise; there are only rules of the body and force. The structure of the individual will dictate her function and capabilities. If you don’t have the capacity or tolerance for details and no eye for precision, then you have no business working with the body.