2. The Basic Bicycle
While the average crunch focuses on the top of your abs, this one will work the hard-to-reach lower portion as well. Lie on you back with your shoulders, hips and pelvis in neutral position. Place your hands behind your head, ready to crunch. Engage you abs (not your back!) and bring your knees up to around 45 degrees. Slowly begin to pedal with your feet, as you would a bicycle and, at the same time, bring your elbow up to meet the opposite knee (right elbow touches left knee, then left elbow touches right knee). Continue through 1 -3 sets, each of 12 – 16 reps.