Beauty is not the goal of competitive sports, but high-level sports are a prime venue for the expression of human beauty. The relation is roughly that of courage to war.
The human beauty we're talking about here is beauty of a particular type; it might be called kinetic beauty. Its power and appeal are universal. It has nothing to do with sex or cultural norms. What it seems to have to do with, really, is human beings' reconciliation with the fact of having a body.
in a footnote, on why we need to reconcile this: "It's your body that dies, after all."
See also note 29