So, what is "the core?" You've heard people talking about it. Is it your front abs? Is it your side abs? What is it? I want you to picture something i want you to picture, god forbid, cutting off your arms or your legs. Guess what? That's your core. Your core is everything except your arms and your legs.
So, we have the mutlifidus which is a muscle that runs in your deep vertebrae. It's in your back. That's why doing total body exercises like squats and lunges and dead lifts are very important, okay, if not more important, then building up your front abs. Multifidus is in the back. Your core muscles wrap around so you have your internal, external obliques. Okay? You have your transverse abdominus, which is in the front, and you have your pelvic floor, which is all a part of your core, as well as your inner diaphragm. All these muscles add up to what we know as your core. So, remember, it's not just a limitation in the front or in the side, it's the whole torso area, it's the basis. It's responsible for transferring weight and power from your lower body to your upper body, okay?
Just training your front abs is not going to get you very far. You got to train total body exercises. So, that's why it's important to think of the core as your entire torso, not just your front or your side abs.