There is definitely a science to getting a toned and strong core—and, lucky for us, fitness and lifestyle expert Christine Bullock shares her formula for flat abs. As founder of the Evolution 20, Super Shred, and Body Reborn fitness series, she knows what it takes to get in shape and maintain it. In fact, she says you don’t have to spend hours in the gym to see results. “I believe it is how you work your core muscles more than how long. With exercises like these that cinch the waistline, you will achieve fast results with less time,” she says.

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