Ah, the good old plank. While the core-blasting move packs a serious punch, it tends to feel a bit boring, since it doesn't call for any movement. If you're like us, you'll basically end up spending the entire duration counting down the seconds and thinking about how shaky your arms feel. That's why we're introducing the (drumroll please) superstrength plank. Not only does it add some much-needed kick to the exercise, but it also dials up the obliques workout. Win win. Begin in a typical plank position, and proceed to pull one knee to your elbow, alternating from side to side. "Remember to keep your shoulders directly over your wrists," advises trainer Franklin Henderson of Stronger and Company LLC. "And if you keep your hips and shoulders aligned, it'll help protect the lower back from injury." Try for three sets of 45 to 60 seconds. If it feels way too challenging, drop down to your elbows for an easier variation. C9 by Champion bra and sneakers, Uniqlo leggings.