
Originally Posted by
Gixxer750
The Big 3 will make your core stronger because they utilize your core musculature. EVERYTHING YOU DO UTILIZES YOUR CORE. IF YOU DIDN'T HAVE CORE MUSCULATURE YOU'D BE A JELLY FISH AND FALL TO THE FLOOR. The CORE is almost like a 4 letter word... everyone uses but doesn't really know what it means. Some say that it is your TVA, IO's, EO's, maltifidus, rectus, and the deep musculature close to the spine. Others say that it even extends to your shoulder girdle and hips/glutes. Either way, the big 3 lifts will and get stronger with increased stabilization, mobility and flexibility of the spine, shoulders and hips. Mobility is in the joint, where flexibility is your muscles... or more precise, your fascia. Stabilization is the ability to perform movement patterns (the big 3 and anything else for that matter) while keeping the skeleton in it's optimal alignment. Thus making it more powerful (when speed is used) and/or strong (performing slower movements).
However, doing the big 3 and ONLY the big 3 or the bodybuilder lifts (using machines---moving in 2 dimensions) ---will NOT strengthen your core. The human frame is meant to move in 3 dimensions. There is specific stabilization training that you can do that can improve your lifts. Rotary or anti-rotational training, chops and lifts performed with a cable.
You mentioned that your midsection is weaker and unstable when it comes to squats......squatting has a lot to do with the mobility and strength of your thoracic and lumbar spine. If you have poor thoracic and lumbar extension, the barbell will "push" you down. You simply don't have the extension necessary to keep the weight up. Remember, when squatting, the barbell must travel perfectly vertical... no arcing. IF THE BARBELL IS ARCING FORWARD, THIS IS ONE SIGN OF POOR THORACIC EXTENSION..... due to lack of mobility/flexibility of the spine and weak spinal erectors, lats and lower trapezius. You may also have tight/shortened rectus ab muscles. Most people do because of sitting too much and slouching.
Also, if you have shredded six pack it is not an indication of core strength. It just means you are lean and watch what you eat. Take a look at power or Oly lifters... they don't have six packs but I guarantee that they have a strong core with plenty of mobility and flexibility of their upper, mid, low back, shoulders and hips.
Remember, if you always do what you've always done, you'll always get what you've always got. So stepping out of the Bodybuilder Exercise box is necessary to achieve what you want.
Hope that helps.