I'd be on my own plan and not on hers. She's changed her opinion of working out w/me b/c she's seen that I'm not like the people she's dated in the past.
When she worked out w/her XH, he tried to control her workout and tell her what to do in the gym. Thus, she had a really bad taste in her mouth about working out w/someone she's involved with.
However, she has been consistently shown that I am not controlling of her and thus is now really excited about the idea of having us motivate each other to work out and hit the gym w/regularity. Plus, it is a proven fact that doing physical activities heightens the attraction - both mental and physical - so it is a win-win for us both.
This is the same thing w/playing softball. I first mentioned it to her after we were together for about a month or so and started to look around for a team. At the time, she said she hated playing w/her X b/c he was hyper-competitive and a poor sport. So, I said I'd look around for a team for me anyway and if she wanted to join me later, she could.
Well, if you don't already have a team you have to wait until open registration and hope to get on an already existing team. So, I was waiting for the open enrollment when GF came back and said she signed us up for her company co-ed team. I had mentioned it off and on, so when she said she'd done this, I was thrilled b/c it meant I no longer had to latch on to a complete bunch of strangers and she was excited to play with me.
So, I think her changes have more to do w/who I am compared to what she's been with in the past and are not really about her wanting to be in control. I could be wrong, but that is truely how it feels from my end.
