10/14/10 - Congratulations! You've made it past the halfway point in Charlotte's 8 Week Ab Challenge! We're entering the tougher half of this challenge so stick with us! Today is a quick one but an effective one that fires mainly the front side of your abs. We also have some waist and back work for a well-balanced core, but the main target is the rectus abdominus and the transverse abdominals. You'll need one mat and one medium-sized dumbbell for this workout. Grab your equipment and let's bust out this quick 20-minute workout!