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The transverse abdominus muscles act like an inner-girdle, wrapping around the sides of your waist. A great exercise for working the transverse abdominus is a basic forearm plank. Begin with your forearms and knees on the ground, with your arms shoulder-width apart. Press up into a forearm plank, keeping your body in one straight line. Hold for 10 seconds, then rest for a few. Repeat this 4 or 5 times. For this exercise you will need a set of dumbbells. Lie down on your back and raise your arms (with weights) in the air (perpendicular to your body). Raise your arms over your head, and bring them back to the starting position. Keep your core engaged the whole time. Dumbbell pullovers can be done with weights anywhere from 3 to 12 lbs (1.3 - 5.4 kg). Select the weight that works best for you. Do 2-3 sets of 10. In addition to strengthening your transverse abdominus, you will want to tone your obliques to achieve a slim waist. To do this, perform dumbbell side bends. Stand up straight with your feet a bit wider than hip-distance. Hold a dumbbell in one hand. Bend to that side, bringing the dumbbell toward your knee. Then return to your starting position. Perform three sets of 10. Once again, select the weight that is best for you. In order to reveal your slim, toned waist muscles you will also need to do a little cardio. Anything that raises your heart rate will work, and if it engages your core while doing so, then even better! Try to do 30 minutes of cardio 2-3 times per week. Some options include: Biking Running Hula-hooping Dancing
Practice forearm plank. Perform dumbbell pullovers. Do some dumbbell side bends. Do some cardio.