How focused and determined you make your workout.
Intensity is mostly a mental process of getting and remaining focused.
Maximum Intensity can help to get you out of a rut. It can lift you over that plateau that your training has reached. It can also force you to maintain focus and cause gains to be made. Be in good health, well rested and eat properly according to a Natural Bodybuilder's Diet . If you are sick, tired or eating poorly, it's difficult to train with intensity, and also not advised, as this can lead to further injury and to getting even more run-down.