When I was a professional Ballet dancer I learned core training, flexibility training, floor exercises, and those training helped me to built up muscles eavenly and also avoid injuries. Since I retired my career as a ballet dancer I have been teaching core training and stretching at dance schools and fitness studios.
Some of my students told me that they have lower back problem, neck problem, stiff shoulders, gain weight..etc. They know their problem but they don't know how to fix it. Even though you are non-dancer or never have done any workouts before, your muscles would be getting weaker or when you train only specific part of muscle you would also get some physical ploblems. So I suggest that you learn how to train inner muscle and strength workout, flexibility streching from my lessons and add new training to your workout routien.