I actually don't have a radio in the house, so she doesn't dance at all. She does walk around a bit to collect gardening stuff, and she does a LOT of gardening, but that is really it.
Her traits are Loves the Outdoors, Self-Assured, Loner, and her aspiration is Freelance Botanist. I tweeted one of the gurus about this problem and she said to make them eat a lot of snacks, so that's what I've been feeding her, but that hasn't made the muscle mass go away, it's just made her muscly AND fat...
Before that I was having her cook a variety of foods and eat it. I finally gave in and used the cheat to readjust her muscles in CAS. The muscle slider was as high as it could go. So far she hasn't reverted back yet, but I'm keeping my eye on her to see what happens.