Planks are one of the most effective ways to engage and strengthen your core, as long as you’re doing them correctly. In this video, learn how to do a plank the right way, so you can enjoy the many benefits of this simple exercise. First, press your hands and knees to the floor, making sure your wrists are directly under your shoulders. Then, extend both legs back and activate your abs by drawing your navel up toward the ceiling. Tip: Engage your upper back muscles, so your shoulders don’t cave in. Hold this position for 20-60 seconds and remember to breathe! Stay tuned until the end for the ultimate counter stretch to your newly perfected plank.