We know what you’re thinking: Everyone knows how to do a plank. But the trouble is, not everybody does it correctly! And if you’re not executing this move with perfect form, you're missing out on its sculpting benefits. Watch Health’s contributing fitness editor Kristin McGee demonstrate how to properly perform the straight arm plank to tone your arms to core.
Here's how to do it: Come onto your hands and knees, making sure your hands are directly beneath your shoulders. Then extend one leg back at a time to form a straight line from your heels to your head. Hollow out your lower abs and pull your shoulders down from your ears. Hold here and breathe for one to two minutes. Repeat three to four times, dropping back to your knees between sets.
Trainer tip: To tighten up your lower abs, imagine you’re cinching a seat belt around your waist.