New York City is having its moment in self-care, as a slew of places focused on wellness have and are opening up in the city. Unlike the traditional spas, a number of these spots go beyond skin and focus on a specific discipline. Stretch*d is a studio that focuses on limbering you up through practitioners who will stretch you out. It feels like part-physical-therapy-studio, part-athlete’s-wellness-studio, where everything is nice, but not over-the-top luxurious. For the signature Stretch*d sessions, you are…