Sigger is right on. I sometimes think that folks get a little too worked up about BMQ, particularly the fitness part. Keep in mind that although you will be tested on BMQ and pushed to your limits and beyond, we do prepare you for that test. It is not in the CF's best interest to fail everybody. It is much better to make sure everybody passes and we do that, not by lowering standards, but raising you up to meet them. Does this mean you should stop all personal fitness training now? Absolutely not! The last thing you want is to show up at BMQ with floppy bits and a severe case of doughnut withdrawal, but by the same token, you don't have to be a tri-athlete either. Keep doing what you're doing and you will be fine. People of average fitness should be OK.
In my own personal situation, I was like you - 10km in about an hour and the in same vicinity with push-ups and sit-ups. On my course, I found myself slowing down so as not to run away from the platoon and I actually gained weight because I wasn't getting enough exercise!