Some dogs can naturally be more "muscular" if that's what you mean??

Otherwise if you're doing everything you can possibly do within your power to try to get her to eat healthier, eat less, and exercise more and it STILL seems she is gaining weight, then I strongly recommend a vet visit. It could be something else, like an underactive thyroid or some other medical problem that is causing her to gain weight.

What food and how much are you currently feeding her (and how much is her ideal body weight, does she currently weigh, and what breed is she?)?