For the Short Dance, the ISU chooses a group of rhythms that the teams have to use that year. For example, this year they can choose from
Cha Cha, Rhumba, Samba, Mambo, Meringue, Salsa, Bachata and any closely related Latin
American Rhythms
The ISU rules for Free Dance music:
*The music must have an audible rhythmic beat and melody, or audible rhythmic beat alone, but not melody alone, and may be vocal....
*The music must have at least one change of tempo/rhythm and expression....
*All music including classical music must be cut/edited, orchestrated or arranged in a way that it creates an interesting, colorful, entertaining dance program with different dance moods or a building effect.
*The music must be suitable for the Couple's skating skills and technical ability.
So it really doesn't matter what style of music they choose, as long as there is a rhythmic beat that is easy to hear and as long as there is some change in the rhythm or speed during the program -- either different pieces of music, or one piece that has some variety or build.