Your usual core routine was working great—until it wasn’t. Don’t get disheartened. With these moves from top trainers, you’ll bust through that plateau and get back to developing that ripped and shredded core.

Be forewarned that some of these are so tough, even the most advanced gym rats may not be able to do many (if any)—at least not right off the bat. “Many people could slop out a few reps of these and not really get anything out of it,” says Eric Emig, personal trainer and founder of Evolution Fitness in St. Louis, MO. “Correct form, of course, is the key.” So focus on doing a few reps of these moves correctly instead of busting out the volume to avoid injury.