This is the best exercise to work upper and lower abs.  Bicycle crunches target all of your ab muscles.  The American Council on Exercise declared bicycle crunches one of the most effective abdominal exercises, according to a small study performed in 2001. all of your ab muscles. Are you working hard at getting those abs in shape but are not seeing any results? Bicycle crunches are The BEST Exercise to work Upper and Lower Abs. PERIOD! The bicycle crunch lifts the torso and contracts the abdominal muscles in the same way as a standard crunch. Your external obliques, the muscles on the sides of your waist, are also activated as you rotate your body to bring a…