Want a beautiful ballerina body without a single twirl? “It takes deliberate moves and zeroing in on posture and breath, so you work muscles deeply,” says Sadie Lincoln, creator of this workout and founder of barre3, a fitness studio with more than 70 locations. Her routine gently sculpts, focusing on trouble zones like the inner thighs, arms, and waist, and also improves flexibility and coordination. It’s part barre, part yoga-meets-Pilates, and all rooted in dance, so it boasts psychological results too: Exercise that centers on breath and gentle movement is good for zapping stress, shows a study by the University of Cincinnati. “Focus on finding both the ease and effort in each move and after you’ll feel leaner and stronger, and grounded, revitalized, and less anxious too,” Lincoln says. Do…