You won't find any "hold a plank for 30 seconds" business here. We're talking moves that challenge and sculpt your core like never before. And none of 'em are done in vain—yes, even if your goal is to feel like a boss in a crop top. Each day, you get a plank workout move that builds upon the last, leading to new challenges at the end of each week. (And before we get started, check out why the plank is still the best core exercise—plus how to do one with perfect form.)
