The Reebok Core Board ($163.99) is a unique training tool that is a low platform (similar to a stepping surface) that rotates, twists and tilts at every angle. Do any exercises that you would usually do on the floor on the core board to improve core stability. The way it works is that the unstable surface reacts to the body's movement, giving your old floor exercises a new and challenging twist.
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Fit's Tip: Try doing crunches on the core board. All you do is lie on your back (on the board) with your legs in the air and do crunches as you usually would. You'll be amazed at how much more you will be working your abs as they are far more engaged on the board. Other exercises to try on the core board: squats, push-ups and lunges.