A great Pilates class is a joy: Your body glides along while pushing, pulling, and moving your limbs in time with your breath. It awakens a wonderland of muscles and tissues you didn't know existed. Even gym fanatics bent on HIIT or boot-camp workouts are catching on that Pilates very well will kick their asses, albeit in a gentle way. Pilates has almost become too trendy, with an ever-growing number of corporate franchises crowding out smaller spots that offer personalized, boutique-style classes. But Breathe Pilates is one of the hidden gems, a bright, airy oasis amid the hubbub of Biscayne Boulevard near 79th Street. The impeccable studio is equipped with six reformers and springboards and an advanced piece of equipment called a "Cadillac." Owner Gretchen Wagoner brings decades of experience, and her meticulous approach to form shines with integrity. A few well-trained instructors are hands-on and attentive, and welcoming group classes are geared toward all ages and abilities.