"Abs are 75 percent diet," says Warner. "You have to clean up your diet. Cut out processed foods. You don't want to eat factory-farmed meats. You want to eat organic fruits and vegetables."
"You want to drink three liters of water a day," Warner tells us. "It boosts your metabolism by 33 percent. You're going to find that you'll be able to see the musculature in your abdominal region if you just drink a lot of water."
"I've always said crunches are a waste of time," says Warner. "They're the slowest way to actually build the abdominals. You need to really be working the upper, lower and the obliques. I like doing crunch-free abdominal work."
"I love free weight training," Warner says. "Better than any crunches or sit-ups, a regular 'man-style' push-up or squat is the best way to get good abdominals."
Warner's pump-up playlist hosts Sonic Youth, Prodigy, Madonna, Florence and the Machine, and Radiohead.
Watch Jackie's flat-ab workout:
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