One of the fundamentals of singing is to understand that singing is of a particular duration. One sings a pitch and it is going to be held for some length of time, whether that be a little time or a long time. The value of a Sustaining Exercise is as the singer sustains the pitch for longer amounts of time, the following happens: 1. a sense of being able to coordinate and maintain healthy muscular balance as well as a steady stream of airflow, neither pushing air nor trying to hold it back as both are dysfunctional, and 2. a development of muscle, like would be achieved if one did a plank exercise for an extended time. Of course, a sustaining exercise on one pitch can be morphed or combined with movement up and down the scale. Then, the focus will also include how to sing a legato line and create beautiful musical phrases!