Sometimes, if a friend or colleague has back pain aggravated by orchestra chairs, he or she will often say, "I need to work on my abs and core. They're weak." I'm always fascinated by this because for years and years, I was told by the media that core=abs, which in not actually the truth (or even close to the whole truth.) So what is THE CORE?
In the words of Katy Bowman, "your core is your center," AKA. anything above the pelvis and below the heart. That includes the front, and the back, folks. So here's the thing-the human body doesn't have much bone between ribs and pelvis because that's what allows us to twist and bend and be bipedal movers. The catch is that we have muscular sleeving around our viscera- think of your core as all the tissues that surround your spine in your middle. In that sense, core includes back muscles, erector spinae, obliques, transverse, rectus abdominus, and heck, your respiratory diaphragm and even serratus anterior, to name a few. Most publications favor the front of the body when discussing core, like this first image here.
So why the fuss? Well, everyone thinks they need flat abs, or six pack abs, or a flat stomach, or some such rubbish, because supposedly, a strong core = flat abs=six pack. Unfortunately, that's not true. Six packing is an aesthetic phenomena and not a functional strength one- the rectus abdominus is the most superficial ab muscle, and it often gets the most attention, but it's job is just to flex the spine, or fold in half. Working on that muscle with a furious passion won't necessarily erase back pain, and could in fact make things worse!!! (Certainly not what the magazines are going to tell you...) Why? Because your poor posture and constant sitting keep that your spine in a slumped position already, and exacerbating that position will only make things worse, especially if you do lots of situps.
So what are you supposed to do with all this information? First of all, visible abs don't necessarily equate strength in the midsection and back. Even amongst female and male competitive athletes, abdominal tone ranges (even though these folks are in ridiculous shape) because of the individuality of the human body. Second, your core may be weak, but we're not talking just about the abs. I'm talking the whole kitten caboodle- back muscles, abdominal, side abdominals, breathing muscles, and more! Your core strength is affected by your movement habits, and if you sit in a chair all day long, your body suffers. Exercise will certainly change core strength, but you have to realize that we are all sedentary humans these days, and our midsections (front and back) suffer for it. The only way to create lasting change is to overhaul your whole movement diet- break up sitting with standing, sit on the floor, get out of the couch, move more...there's no 5 crunches that will solve all of your problems forever. Core strength is your ability to move from your center in a supported and balanced way, which includes standing, sitting, walking, running, playing your instrument, singing...all of it. Above all, please stop thinking your core are your abs, and just your abs. You've got a lot more muscles holding you up and sleeving your spine, and they need some love too.
Newsflash: Your core is in the front and the back, people!!!