I did ballet from age 4 until age 16, my last two years being at a professional company in the corps. So I thought I would give my "insight" on this topic.
Ballerina Arms / Legs: The lean muscle developed in ballet is a result of a specific type of training that simultaneously combines strength training with stretching. Ballet training, when done correctly, builds lean, elongated muscles as opposed to bulky muscle; for example: we are taught to never "grip" with our quad muscles when doing a "developé", we are taught to "lift and lengthen." The whole idea is to stretch while strengthening. Many ballet dancers do pilates and/or yoga on the side (at my studio, pilates was required) as these two things promote the same kind of lean muscle building concept. You could try beginner pilates / yoga classes. If this is not doable, try doing strength training in your arms / legs (pushups, squats, small weughts, etc) and follow up with cardio and stretching.
Grace / Elegance: The gracefulness of a ballerina comes from years and years of training and is not easily attained. A ballet dancer is constantly working on her flow, unity, and overall performance. I think that gracefulness is no more a physical thing than a mental thing that is a result of passion, emotion, and being comfortable with yourself. You say you remember positions from ballet? Try this: stand in front of a mirror and practice moving your arms through each position...low fifth, to first, to high fifth, to second, back to low first. It may seem silly, but this is what I would do at home. Lift your arms from your back and keep your shoulders down. Play with you fingertips, make them soft and lengthened. Then, take this to the ice- do forward bubbles and practice flowing to each position with each bubble. This will help unify your grace. I think that gracefulness in the arms is what will be easiest (but not easy!) to improve, as for full body grace for, say, in a program, I think that comes from tons of practice in the program, becoming comfortable with that. I consider myself graceful, but when working on my new program, all grace and elegance flies out the window! But it comes back the more I work on it, perform it, ect. I think you will find that by improving your posture and arm movements, you will feel and appear more graceful and elegant.
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