“I love planks,” says Prevention’s Fitness expert Chris Freytag. “You get a killer core workout but it also works your upper body, chest, and helps with shoulder mobility.” It engages more muscles, turning a great flat-belly exercise into a total-body toner. This week, take your plank to a new level with Freytag’s more challenging version that combines two effective ab exercises in one. When you’re trying the exercise, be sure to keep your abs tight, pulled in towards your spine, and engaged throughout the entire move. And don’t allow your hips or lower back to sink in the top of the plank, keeping your back straight, says Freytag. This gives you the greatest range of motion and helps prevent injury. Ready to see how it’s done? Watch the video to learn how to do the roll-in plank with perfect form, then try the exercise for yourself! More from Prevention: 6 Surprising Moves For Flatter Abs
