Wanting a tight tummy fast? Crunches won't cut it. "These days, it's all about working the complete core, instead of just your abs," says Anna Kaiser, a trainer in New York. "When your entire core is strong, your waist will be smaller." Start out your workout sessions with at least 30 minutes of cardio to elevate your heart rate. (Your best bets? Dance cardio or kickboxing, since both engage the entire core.) Then, follow up with the moves below to tone up. Says Kaiser: "You will feel noticeably stronger and firmer after two weeks of doing these exercises, four times a week."
Target zone: Obliques (the sides of your abs)
How to do them: While standing up, extend your arms overhead, holding two five pound weights (one in each hand), with your palms facing forward. Keeping your arms next to your ears the entire time, bend from side to side, only moving at the waist. Do three sets of 20 repetitions, pausing in between each set.
Target zone: Rectus Abdominis (front of abs)
How to do them: Lie on your back with your hands placed behind your head, and your head and shoulder blades raised off of the floor in a crunch position. Lift your right leg up to the ceiling, and extend the left leg out in front of you (like a scissor). Keeping both legs lifted off of the ground, pulse the right knee in toward your forehead, for 30 repetitions. Rest, then switch legs. Repeat each side, three times.
Target zone: Transversus Abdominis (the deep ab muscles that go across your body)
How to do them: Start in plank position with your hands flat on the ground. Tucking your hips under, pull the right knee over and tap it to the left elbow. Pulse for 20 repetitions, then switch legs and repeat three times on each leg.