Muscular And Tanned Male Naked Torso
Credit: David Castillo Dominici
Whether or not it's ever said, most people are looking to flatten and define their abdominal muscles.  The holy grail is the "six pack":  abs so strong and developed that they are clearly defined when you take off your shirt. Whether your a guy looking for the best six-pack on the beach or a girl looking to tighten up her midsection, you can get there without doing a single sit-up, crunch or conventional ab exercise.  In this article you'll learn some of the best excercises to develop your midsection without doing a single crunch or sit-up
First it's important to understand the primary function of the abdominal muscles. In short, the muscles of the midsection allow for stability during functional movements such bending over, picking up objects, running, and supporting your spine when extended. Given that this is what your abs were meant to do, we'll focus on functional movements that activate your muscles as they were intended.   The exercises following will all emphasize constant tension and functional stability. 

The Deadlift

Bodybuilder Training In A Gym
Credit: David Castillo Dominici
The deadlift is known as one of the "powerlifts" but there may be no other exercise that forces your midsection to create more tension. Start with 3 easy sets of 10 and gradually increase the weight, workout by workout. Prior to picking up the bar make sure to tense your lower midsection and grab the bar as hard as you can. The tension you are creating should be felt throughout your whole body. 

The Overhead Squat

Overhead Squats
Credit: yayomo
Squating with a weight overhead requires your core muscles to stabilize your midsection as you lower and raise your center of gravity along with the weight.   This movement requires some skill and flexibility to master especially as the weights get heavier.  You will quickly notice if you have mobility restrictions in hips, shoulders and ankles.  Start with sets of 10 that you can mange easily, but you can certainly do sets of 5 or less to challenge your ability stabilize your core and stay tight.

The Dead Bug

The Deadbug is a little known exercise that is great for developing the muscles that stabilize the core by resisting twisting motions.  This is the only exercise that you will do on your back. Setup by lying flat on your back with you arms and legs sticking straight up in the air. Lower your right arm so that it is now behind your head and simultaneously lower left leg until it taps the ground.  Next is the tough part. Bring the lowered limbs up while bringing the raised limbs down.  The goal is to do as many as possible while keeping your lower back flat against the ground.
A video demo:  

Do 2-4 sets of 20 reps per arm-leg combination. 

Once you have built up the muscles, you'll need to be able to show them off. Depending on your body type, good nutrition habits are the best way to ensure you are lean enough to show off your midsection.  Opinions differ on this but reducing carbohydrate is a very effective method of facilitating fat loss.  Sticking to a diet rich with high fiber vegetables and high quality protein and fat, should get the job done. You will also want to drink lots of water everyday.  Take a look at this article series if you want to learn more about fat-loss:  An Unconventional Approach to Fat-Loss
Give these recommendations a try. You'll find that with some hard work and a disciplined diet you can build a great core without a single crunch. 
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