For the body to execute efficient athletic movement all parts and systems of the body need to work together in harmony. Movement is a symphony not a solo. You can?t do a ?cardio? workout, just like you can?t do a ?neural? workout. It is impossible to isolate various systems of the body. All systems of the body work at all times with the demand on a particular system determined by the intensity of the activity. To continue the symphonic metaphor a section of the orchestra is featured or highlighted while the other parts of the orchestra are still playing, albeit in the background.