Music helps us perform by taking over a vital piece of the task of moving, the rhythm travels in through our ears and down our auditory pathways to the supplementary motor area. There it joins forces with brain activity that is signalling when to move, helping us to keep pace by providing an external timing signal. Or to use a sporting metaphor, it not only helps us out of the starting blocks but it helps to keep us going until we reach the line.
Music helps the brain better plan movement. Music is the cue.