Quote:
Originally posted by Naxis:
There most certainly are upper and lower abs. The rectus abdominus is one muscle but the upper and lower portions control different motions. Isolating them works it's focus area more. That is not to say that crunches don't involve the lower abs, but they are not the primary part of the muscle used for that action. |
Actually, Hoyd is on the right track here. There is no such thing as upper and lower abs when speaking of muscle contraction. A good way to test this is to place your hand on your upper ab region and attempt to contract your lower abs without your upper abs contracting. It's impossible! Another way to prove this is with basic biomechanics. There are a number of muscles that are located in the abdominal region but the muscles that everyone basically focuses on... the ones responsible for the "six pack" are the rectus abdominals. These muscles like either head of the bicep group or the rectus femorus (in the quads) all have only two areas of insertion. In order for there to be an upper and a lower portion there would have to be an additional insertion point midway between the ribcage and the pubis.
Those "separations" on the abs are about the equivalent "in layman's terms" of taking a rope and tying it midway down the upper arm and thinking it will effect your contraction. (very rough comparison but you get the idea.) Those separations have no bearing on ab development.
Most often people will say that they feel something different when they do lower ab work. This has more to do with the ability of some to get closer to a FULL contraction in the rectus abdominus. (ever done super-slow full range leg extensions or tricep presses and noticed that you are more sore down near the elbow or down toward the knee?) The proper way to get the best contraction in the rectus abdominus is to get in a crunch possition preferably with your feet elevated and raise the chin and shoulders toward the ceiling while bringing the rib cage up and toward the pelvis at the same time... shortening the distance between the two points and causing your abs to work on your spine like a long bow and giving you a perfect contraction. ONE BETTER is to do these on a swiss ball so you can get a full stretch between contractions, however, this is not recommended if you have lower back problems. If you have lower back problems whether you do the exercises off the ball or the floor try to avoid to much of a stretch in order to keep the psoas out of the action (at least until you build up some strength).
LATER,
ScottGee
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