I was listening to an NPR podcast about the transgender situation and one of the guests on the program was a D1 swimmer from Harvard. Apparently he was an all-american as a female, but once he came to Harvard he transitioned to male and joined the men's team. CBS story is below:
I really wish I had heard the program live because I probably would have called in and asked a question or two. He was being praised for being the first D1 trans athlete and everyone was talking about how it must have been hard to move from the women's team to the men's team, but no on addressed the elephant in the room: the converse situation.
I don't think anyone is going to make an effort to pretend to be trans just to win swim meets, but what if a guy truly identified as female and wanted to transition and he also happened to be a runner or swimmer or basketball player? What happens in that situation? Obviously it could happen. It happened with the Harvard swimmer in the link above.