This requires further scientific study. Where do I apply for a grant to do research on the subject? It would necessitate many hours of my time, but I am willing to make the sacrifice.
I am not a pedophile. Therefore volleyball.
Wonderful. If this thread has accomplished anything, it’s turned up a handful of pedophiles. 
If we’re going with women who are seriously pursuing a sport, then for the reasoning evident throughout this thread, volleyball players are my choice.
However, I’ve dated a couple of women who did gymnastics on a non-competitive level (they didn’t have fireplug bodies, so weren’t ever going to be competitive), and the limberness and flexibility alluded to by The Scrivener really is a nice benefit. Similar to dating a ballet dancer or someone into yoga.