Drew Barrymore calls her trainer "one of the greatest," and now you too can reap the benefits of her expertise! Marnie Alton, fitness expert and founder of the M/Body Exercise Technique and Studio, has created this quick 10-minute routine just for POPSUGAR! Get ready to work your glutes and core like never before! Her barre-inspired workout is effective and unique in that there is no ballet barre. Instead, you're standing without any equipment the entire time.