Real talk: Crunches and sit-ups are the worst when it comes to working out. They're boring and ineffective, and yet, we still find ourselves doing them over and over again. Well, no more. Life is too short to waste time doing hundreds of crunches. From now on, we'll be relying on the four core moves in the video above. Watch and get ready to tone up and slim down all over — without doing a single crunch or sit-up.