The perennially popular yoga, ballet and pilates all owe their success to what has become the latest buzzword in fitness: Core Strength. Core strength refers to the torso muscles - from the glutes and abs to the back and neck - those muscles that literally keep you standing tall, strong and erect. Athletes and dancers have always understood the importance of core strength, and as our population ages everyone is beginning to herald workouts that concentrate on these all-essential muscle groups. After years of relying on yoga, pilates, ballet and various combinations thereof to work these muscles, the fitness industry is now developing routines strictly for Core Strength. This is the fitness trend of the decade.