Really? That's encouraging. I've done some swimming stints before but I was never able to keep it up for more than a couple of weeks.
What is that?
It becomes a good kind of addiction after a short while, we've got you now
Pilates is sort of like Yoga but if focuses mainly on your Core Muscle, which is the muscle that is most active while lifting etc, if you have a weak core muscle it will but strain on your back and we know what happens from there.
The execises that I do are pretty basic, but they aren't yoga-ish at all.
I suggest you get in cotact with a Physiotherapist/Personal trainer that can tailor a program to your needs.