Over the winter, I remember reading a couple of cyclocross race reports, several of which included complaints of back pain. And since a lot of the problems in cyclocross riders will cross over into spinning class participants (if not necessarily to triathletes), it's time to address the issue of (dramatic pause) . . .
The psoas.
Wait. The Pso-what?
You may have heard of this muscle. Or you may have heard the term iliopsoas, which is a combination of the iliacus and the psoas major (not the same muscles, but close enough that there's a combined term for them). The psoas is a deep hip flexor, and acts to raise and externally rotate the leg at the hip. Know what activities involve frequent frequent flexion at the hip (and external rotation, if you have something wonky going on with your form). Yep. If you're a cyclist, a runner, a stair-stepper, an elliptical-user, or (I assume) a cross-country skier--in short, if you do cardio on the land--I can almost guarantee that your psoas are tight.
And the psoas originates at the spine; it's attached directly to your vertebrae (from T12 to L4). So when it's tight (or shortened, for example when you're sitting), know what it does? That's right. Cranks that lumbar spine forward! So if you've got one of those crappy jobs that requires you to sit at a desk all day, the psoas is constantly shortened. And if that job happens to entail a long commute (look down at your legs next time you're driving; are they flexed and externally rotated at the hips?) AND you're a cardio person? Yeah, you're pretty much screwed.
We've talked about the psoas before; it figures prominently into the anterior pelvic tilt associated with swayback (lower-crossed posture). It's not the only muscle acting on that posture, but it definitely contributes. And if you drive a lot, sit all the time, and are an avid biker (or runner, or both), it stands to reason that psoas tightness might be acting on your whole lumbo-pelvic area pretty powerfully.
But what does that have to do with this searing pain in my back?
Back pain related to tightness in the psoas usually presents as pain or pressure in the low back somewhere (or possibly everywhere) from the low middle back to the tailbone, off to the side (the pain is almost never right in the midline--that is, directly on the spine, 2). It might be relieved by sitting or laying with the knees bent (later I'll show you a position in which you can lay that--in my opinion--offers instant relief).
There are nerves all up in the psoas; the origins of the femoral nerve (which is the main lower-body nerve of the front, the sciatic nerve being the main nerve on the posterior side) are "invested within [the] psoas" (3). And the femoral nerve itself emerges between the iliacus and the psoas, so overactivity of the latter can cause compression (read: PAIN) of that nerve.
Keep in mind, though, that overactivity of the psoas isn't the only cause of back pain. So if you're getting constant pain, stabbing pain, or shooting pain down your back, you should go get your back checked out by a legitimate medical professional (FYI, I'm not one). But most of the exercises I'll recommend for you here are the kinds of things that won't hurt, might help, so you may as well give 'em a shot.
Yeah, yeah. Shut up with the stupid anatomy and tell me why I hurt!
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