If you’re cranking out the crunches and seeing minimal results, it’s time to rethink the way you work your core. Enter this quickie routine from Megan Roup, creator of The Sculpt Society. Using a pair of sliders or two hand towels, you’ll complete this entire circuit in a plank position, working all those hard-to-hit abdominal muscles that will sculpt and strengthen your core. Start by doing all of the moves on the right side before going on to the left, making sure you perfect your plank before you place the sliders or towels under your feet. Do the entire circuit twice on each side for a fast burn you can squeeze in anywhere.