If you're tired of planks and crunches, you need to try the swan dive. It works your abs in a prone position, which is an awesome way to target your back, as well as your entire core. Here, Kristin McGee, Health’s contributing fitness editor, guides you through the move.
Here’s how to do it: Lie on your stomach, stretch your arms overhead, and point your toes. Inhale and lift your legs and chest as high as you can as you circle your arms to the sides and behind you. Hold for a count, then return to starting position. Do 6-8 reps.
Trainer tip: While you hold for a count, imagine your legs being pulled out and back away from your hips.