What is the woman good at?

M: Is it true that you don’t swim at all now?
W: I’m afraid so, I’m too old.
M: But you are only twenty.
W: That’s too old for a swimmer. If I swam in an international competition now, I wouldn’t win. So I’d rather not swim at all.
M: But don’t you enjoy swimming?
W: I used to, when I was small. But if you enter for big competitions you have to work very hard. I used to get up at 6 to go to the pool.  I had to train before school, after school and on weekends. I swam thirty-five miles every week!
M: But you were so famous at fifteen. And look at all those cups.
W: It’s true that I did have some wonderful memories. The Olympics were very exciting. But I missed some important things too. While other girls were playing, I was swimming.