As we concluded in part one, hanging knee-raises, straight-leg raises, knee-raises off the edge of a bench etc. simply don't work your abdominal muscles properly. We have to narrow it down to the one and only action the rectus abdominis can do - decreasing the distance between your rigcage and the pelvis.
Sounds like the good ol' sit-up, like you used to do in P.E. in school until you puked, doesn't it? You were lying on your back, wedging the toes underneath something, clutching your hands behind your neck, and off you were in squeezing the crap out of the abs, right?
The idea still holds true, but there's a few important points where correction is needed. First, forget about wedging your foot under something. Instead, you should lie down on a mat, so that you can put your heels against the edge of it. Your knees should be 90 degrees and your hips approx. 45 degrees bent. Now, the trick is to lightly press downwards/backwards with your heels (hence the edge of the mat, as resistance). The reason for this is that damn hip-flexor again - if you brace yourself against something, you are doomed to use the Ilio-psoas to some degree, whereas you're sure to get it out of the action by activating your hamstrings (when pressing the heels against the mat/floor).
Secondly, forget about those cool all-the-way-up situps you always see in the Van Damme-movies. The abs can only do this small, tiny range of motion, so why would you bother to continue raising your upper body until your elbows hit the knees? I mean, really? The abs are contracted to the max when your shoulders are 1-2 inches above the ground, so just what do you expect to accomplish after that? Concentrate on going from a pretty stretched out position with your head hovering just an inch or two over the ground, shoulders flat against the ground, to the point where you cease to get any closer to the pelvis.
Put your hands on the abs to feel them work. A good trick to make sure that you're training your abs correctly is to have your training partner put his/her fingertips under the small of your back, and as you crunch the fingers should be pressed deeply into the mat. Thirdly and lastly, do NOT put your hands behind your neck. If doing so, you will be tempted to start pulling at your neck to get the last few reps out, which will put unnecessary strain on this fragile part of the spine.
Like I said, this is a very short movement, and to others it might look like you're just dogging it and doing incomplete reps. Screw them - when summer comes and you'll be able to show off a powerful sixpack, created by effective training, I can assure you that nobody will be laughing.
And this, ladies and gentlemen, is the basic, correct crunch. It might look boring, but once you've mastered it in all its simplicity, you'll find it a great aid in your quest for excellence. As you grow stronger, you might want to hold a plate against your chest with your arms crossed over it in order to increase resistance.
Another good ab-killer that actually works is kneeling crunches in front of a pulley. It's pretty simple: Attach a thick rope to the top-pulley, grasp it with a comfortable grip and kneel in front of the machine. Personally, I prefer to use a rather long rope and hold my hands 1-2 inches below my armpits in front of my chest and having my upper body in a 30-45 degree as starting position, so that the rope is against my front delts. This takes some of the weight off your hands and puts it as pressure onto your front delts, as I've found the hands to be the weak link when I start going into heavy poundages. I've done crunches with 180 lbs, and even with gloves the skin on the lower part of your hand can get pretty burned.
From that 30-45 degree starting position, you simply contract your abs as much as possible. You will not get your forehead all the way down to the ground, and have no reason to do it either as your abs has such a short range of motion. I'd like to raise a finger of warning though: when you go back up you probably want to stretch the abs out a little before crunching again. This is no problem, as long as you make sure not to overdo it. Better safe than sorry, so avoid any major archings of the back that might put unnecessary strain on your spine. If you're light but have strong abs, you might want to wedge a 45-lb plate behind your knees to weight you down. Have your training partner put it so that it rests comfortably on your calves as you work out.
Bull$hit Ab Training Devices...
Now it's time for a lighter subject: those hilarious ab-training devices that are sold on TV and surprisingly enough seem to be bought by about every yahoo with a credit card these days. So far I have yet to see a single health or training-related product advertised on TV that does NOT have claims so ridiculous that it makes you wonder why nobody has sued them yet.
First of all - whenever they talk about instant results, only 5 mins per week required or spot-reduction of fat, they're lying through their teeth no matter WHO they paid off to say the opposite! Let's get it straight - there are no shortcuts!! Ever!!
Secondly, look at the actual range of motion: If the motion does NOT decrease the distance between the ribcage and the pelvis, it does NOT train the abs sufficiently. I remember one device in particular, shaped like a stealth-fighter or something, where you were supposed to grab onto two handles, put a pad against your tummy and then use your arms to pull the device towards you so that the pad would sink into the device bracing itself against your abs. Umm… In that case I should great abs by doing barbell-rows, as it's essentially the same motion.
What did the action? The ARMS were PULLING something BACKWARDS - as in a barbell row, which I'd like to call a back-movement. Did the distance between the ribcage and the pelvis change? Nope. What we have is a static exercise for the abs, which does not train the muscle sufficiently. I mean, hey, if you build your abdominal muscles by resisting outside force, you could build the abs of your life by letting your little brother hit you repeatedly in the midsection with a baseball bat!
Any volunteers for a study?
NOTE: This is part two, click here for part one!