Turn Up the Volume on Your Planks (and Rock Your Abs) With This Variation

The shoulder scissors move is like a sliding elbow plank; in one fell swoop, you’ll work your triceps while leaning out your abdomen. All you need are two small towels to place under your elbows (or paper plates or gliders if you’re on a carpet). Here’s how it’s done! Related: A 30-Minute Fat-Frying Workout That…