Paul Chek has been teaching this for years. Let us look at how the abdominals really work and get away from this isolationist exercise ideology by returning to function.

Crunches are probably the single most misunderstood and abused exercise in the entire fitness industry. Somewhere along the way, people realized that if they squeeze their midsection together they will end up ‘feeling it’ in their ‘abs’ and some how they equate this to having a flat stomach or mid section. 

In the case of doing crunches for a flat stomach and showing off your abs we can just throw logic right out the window. Trainers and many people who know better still ignore the most basic principles of anatomy and physiology all in the quest for a flat stomach.
Here are the facts:
1) Crunches will provide stimulus for your abs to get stronger and probably grow. (yes that’s right, if you do enough of them and do them intensely they will grow) A crunch is basically a weight training exercise for your abs, the same basic idea as doing a bicep curl. You are working the muscle, which will eventually make it stronger and make it grow. But for some reason people think that a crunch will burn the fat off their stomachs and keep the muscles there small and compact.
2) You cannot spot reduce fat. In other words, working a specific muscle does not burn the fat around that muscle. Your body burns fat systematically all over, not just on one place. For example: if you did 100 bicep curls every day on your left arm, you would end up with a muscular left arm, but your left arm would have just as much fat as your right arm, same deal with crunches. If you do 500 crunches every day, you will just have bigger stronger abs, but all the fat you always had around them will still be there unless you adjust your diet and the rest of your daily activity and workout schedule to lose fat.
This last point is probably the single most misunderstood point of all. People continue to do crunches thinking they will reduce the fat around their mid section and stomach.
3) Crunches may not be the safest exercise for your spine and lower back. A growing body of research shows that a crunch is in fact one of the worst positions you can put your spine in. Most fitness professionals and so called ‘experts’ do not have any formal biomechanics research training. Therefore they are most unaware of the science behind the shape, structure and function of the abdominal oblique, and lower back muscles. If they did they would definitely think twice about doing or recommending anyone to do a crunch.
Colleagues of mine are doing research on spinal and lower back injuries. And in their lab the only way they can guarantee to herniate a spinal disc is to put a test spine into a severe crunch! Yes, a crunch! The exact same position people put themselves in hundreds of times every workout. In reality the abdominal muscles are not meant to pull your body into a forceful curling or crunching position. They are meant to stabilize your trunk or “core” as it is being called now. In other words they are meant to simply hold your core in place as your arms and legs move and do work such as running, jumping, throwing and the like. All of these motions will work your abs without forcing you into the potentially dangerous position of a crunch.
So how do you get a 6 pack without doing crunches?
Simple, eat less food, and burn more calories. Being able to see a well defined 6 pack has nothing to do with doing any sort of ab exercises. It has everything to do with burning fat. As soon as you strip away enough fat you will eventually see that you already have a nicely formed set of abs. As you have been developing them your whole life every time you stand up walk, run, jump, and every other form of activity you can think of.
If you feel like you need to work on your abs, avoid crunches and do exercises that work them in a pattern that they are meant to be used in. Such as planks, side planks, stability ball roll outs, planks on a stability ball, all forms of push ups and modified push ups, medicine ball throwing, sprinting, swimming. There is more, but I think you’re getting the picture. Incidentally all of these exercise will work the muscles of your core in a balanced manner (unlike crunches which do not work your oblique or your lower back muscles).
Even though crunches will work your abs to some degree there is good evidence to show that this is by no means the best or the safest way to work them. The associated risk to your lower back in most people’s case should outweigh any benefit they think they are getting by working their abs in this way. Each person should weigh the risk and reward of doing crunches for the sake of having bigger stronger abs, and the risk of injury and chronic pain and problems with their lower back. And lets make no mistake about it, crunches never have and never will give you a flat stomach or cause you to lose fat off of your midsection.
John Barban is a Varsity Strength and Conditioning Coach and has his Masters degree in Nutrition. He is the author of a womens specific workout called the 6 Minute Circuits Workout you can find at [http://www.6minuteCircuits.com] He is also the performance Training Advisor to a womens exercise and nutrtion resource [http://www.grrlathlete.com] Ask John questions directly at the grrlathlete forum http://www.grrlathlete.freeforums.org
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