The lower abs are some of the hardest muscles to tone. This is a simple and effective way to make those muscles work!! "15 reps Sit at the front edge of your chair, hands grasping the sides of the chair. Keeping the spine straight, lean back until you feel your abs engage. Keeping the knees bent and legs together, lift your knees up towards your chest and slowly lower them back down. Make sure you're not leaning into your chair back. Keep your abs pulled in tight and your torso still. Exhale as you lift the legs up and inhale as you lower them down."