For as long as I can remember, “strengthen your abs” has been one of the routine pieces of advice doctors and therapists have given their low back pain patients.

Here’s the logic:  The abdominal muscles support the back and stabilize the trunk, so strengthen your abs (your “core”) and you’ll be free of low back problems.

Unfortunately, the truth is never quite so simple.

Surprisingly, when researchers study the relationship of abdominal strength to back pain, they come up empty. There’s no clear-cut scientific evidence that performing abdominal exercises protects your back.

It’s clear we have to junk some of our old thinking. But what takes its place?

Some clinicians are ready to abandon biomechanical models of low back pain almost altogether. To them, since anatomical markers for back pain are hard to define (certainly MRI’s don’t do much good) and physical interventions (like abdominal exercises) don’t help, it’s better to shift the focus to social, psychological (stress anyone?), and chemical (i.e. chronic inflammation) factors as causes of back pain.

It’s true that social, psychological and inflammatory factors figure into the back pain phenomenon. Every treatment program should acknowledge them.

But in my practice I recognize another element in the back pain equation: it’s not the quantity of your abdominal strength that counts, but the quality of the use of your core support.

The ability to differentiate in the firing of your abdominal layers, and their ongoing use for postural support, is a critical factor in the long-term management of back problems.  The rectus abdominis, the strongest of your stomach muscles, shouldn’t engage for the purposes of trunk stabilization – instead, that role that should be played by the deeper layers (the obliques and transversus.)

This issue has just begun to be tackled from a scientific research point of view. It’s tricky to measure the activity in different layers of the abdominals in a living, moving body. But here’s one research study that’s tried. It shows a correlation between deeper-abdominal activation and freedom from back pain.

That’s why I can’t just hand you pictures of three ab exercises and tell you to do them. I’ve got to actually show you how to do them properly, and give you a way to tune in to your body so you can self-monitor your pattern of use. Then you can expect to notice the results.