Core fitness is a base in which much of the bodies strength comes from. Strengthening your core is a workout that you will feel more than see, which is also why is has a tendency to be overlooked in many workouts. This video below has some excellent exercises that will tighten up any midsection no matter what the condition. This video also gets to the obliques and includes some shoulders in the workout as well. This is a very good combination of exercises and will challenge even the most fit athlete when done correctly. Enjoy and work on those cores. You only get one!