Well any time you insert something into your vagina(finger, tampons, etc), you can break the hymen, but it can also be broken by sports, riding a bike, or other simple exercises. I don't know when my hymen broke, as I had played soccer and other sports since I was 5, but I started using tampons at 12 and was very far from being sexually active. I didn't have sex until 20 and my hymen broke long before that, which I'm glad it did.