When trying to understand stability it's important to understand a little anatomy of the abdomen and how the muscles of the bodywork. First thing to understand is muscle function can be determined based on depth. The more superficial muscles, ones you can see just below the skin like the deltoids, rectus abdominus, pectorals, deltoids etc. are for power and gross motor movements. The deeper muscles; muscles not seen under the skin like the multifidus, transverse abdominus, longus colli etc. are for fine motor movements and stabilization. Of the abdominals, the rectus (6-pack muscles) are the most superficial while the transverse abdominus is the deepest of them, therefore making them the most important for lumbar spine stability.
Secondly, stability comes from balance between the muscle group; side to side and front to back. Most folks when in the gym work in only one plane, sagittal, of motion and neglect the other two, transverse and frontal planes. I don't believe they do it intentionally but it happens nonetheless. So before you go to the gym google a few exercises in the transverse and frontal planes. Some will be pretty easy but most will be foreign.
Thirdly, posture plays a big part in proper activation of stabilizing the core. Some will argue form isn't as important as feel and vice versa. I would agree with the later, if you can get into the right position you will feel the right muscles working by default. It's my opinion that without the right posture you won't be able to activate the right muscles in the right amount to properly stabilize the body while in motion. Therefore bad posture will decrease stability, subsequently resulting in more frequent injury.
Fourth, Open Kinetic chain v. Closed kinetic chain exercises. Open kinetic chain (OKC) are exercises where the extremity moves about the body. Closed kinetic chain (CKC) exercises are those where the extremity is in a fixed position and the body moves about the extremity. When training stability into the body or a specific joint it's important to focus more on the CKC type exercises to effectively balance the joint as it functions with the torso. Good examples of each are OKC- bench press, leg extensions, bicep curls. CKC- squats, push-ups, chin-ups. OKC can be good for isolating one muscle group where CKC requires a functional balance between all the muscles of a joint to maintain a range of motion.
Lastly, but most importantly, breathing is possibly the most important aspect of lumbar and whole body stability. We all breath but many of us fail to breathe properly. Proper breathing requires the use of the diaphragm to descend from the chest into the abdomen. In order to do that properly the internal/external obliques along with the serratus posterior need to be activated to anchor the ribs. Most of us, due to a number of reasons, fall into a pattern of chest breathing. Chest breathing is a condition where the patient relies on the superficial muscles of the neck, back and ribcage to elevate the ribs relative to the diaphragm in order to fill the lung field. The usual result of this is regular tension in the neck and low back pain.
If this article made you think a little about how you approach your core training please feel free to reach out for more information. You are always welcome to a 15-minute free consultation as the schedule allows. I hope you've found this article helpful on your journey to a fitter, healthier you!