by Eric Cressey
In Part I of this series, we outlined several crucial prerequisites to understanding the nature of lower back pain.
In this installment, I've got a few more thoughts in this regard, and then we'll get to work on strategies for preventing these problems in the first place, and working around them once they're in place. You don't need me to tell you that back pain — any chink in your armor, for that matter — will prevent you from making progress in the gym.
We'll pick things up with our ninth tip:
9. Hip mobility is imperative!
I touched on it in a previous tip — and for the last, oh, four years, but it warrants mention again here, as it sets the stage for much of what we're going to talk about.
Anecdotally, in spite of the fact that the Magnificent Mobility DVD was originally introduced as a warm-up resource, Mike Robertson and I have gotten quite a bit of feedback from folks who have eliminated lower back pain just from using the tips in the DVD.
There's a considerable amount of research out there to suggest hip rotation deficits are highly correlated with lower back pain, but at the same time, a few studies have shown no correlation. This is where it gets interesting.
Van Dillen, et al. brought to light a great point when they noted the following:
"One potential reason for the equivocal findings could be because prior research did not take into consideration a person's need for full hip rotation motion during regularly performed activities. It is possible that a limitation in hip mobility may contribute to a person's LBP problem only if the person repeatedly performs activities that require full range of a particular direction of hip and trunk motion."(1)
In other words, if you're looking at a sedentary population that doesn't use (or need) much hip rotation, it's going to be tougher to see a difference between those with healthy and unhealthy lower backs.
However, look for that same correlation in populations — rotational sport athletes and lifters, most notably — that are constantly pushing the limits of combined hip and trunk motion, and you'll see that it's a huge issue right away.
You want more hip motion and less lumbar spine motion, and in lower back pain patients, you see more of the latter. And, to take it a step further, it's my belief that in those with chronic back pain, it becomes a vicious cycle. Once you have back pain, you move less acutely (due to spasm) and chronically (due to fear of re-injury).
In the aforementioned study of rotational athletes by Van Dillen et al., the patients in the lower back pain group had experienced an average of seven years of back pain, with an average of 9.3 "incidents" in the previous 12 months.
If you conservatively estimate that each incident set them back for a week at a time, you're looking at about 20% of their lives where they're miserable. And, this doesn't even include the folks who have very acute back pain; "incidents" had to involve at least three days of limited performance in activities of daily living.(1) Pain-induced immobility is a huge problem.
As a Cliff's Notes version, it is safe to say that you have to have solid range of motion in hip internal and external rotation, abduction and adduction, and flexion and extension in order to protect the lumbar spine.
A deficit in any of the above movements will mean that you'll compensate with too much range of motion at the lumbar spine.And, if a back injury takes place, this hip immobility will get even worse, as you'll move less to avoid pain.
10. Recognize that shear stress will injure a back more easily than compressive stress.
At the risk of starting an evolution argument here at T NATION among the stamp collectors who live in their parents' basement, I'm going to go right ahead and say that we evolved a little something like the illustration at the right.
As you can probably imagine, in the "ideal" posture we'd like, our spines evolved to the point where we're pretty well structured to tolerate compressive forces.
Conversely, you don't see a whole lot of gorillas squatting huge weights (although it's my understanding that they are freaky strong). And, anecdotally, the computer posture folks among us always present with more low back pain. So what gives?
Well, imagine putting a barbell on the upper back of the guy in the middle in the picture at right, and then do the same to the guy to the far right. For the one in the middle, we're looking at mostly compressive forces.
For the guy on the right, while there are still compressive forces, we've also increased shear stress (particularly on the descent of a squat), as the barbell is farther away from the individual's center of mass and the ideal axes of rotation (hips and knees) for the squat movement. It should come as no surprise that the guy with the poor posture is the one who's going to get hurt — and this has been demonstrated in the research, according to Dr. McGill.
The spine doesn't buckle until 12,000-15,000N of pressure are applied in compression, but as little as 1,800-2,8000N in shear will get the job done.(2) Here's where it gets interesting, though.
In a 1991 study of national level male powerlifters, Cholewicki et al. found that average compressive loads with the deadlift were 17,192N, which is over 2,000 N more than it takes to buckle a spine in laboratory settings.(3)
Clearly, this speaks to the role of the body's active restraints (muscles, tendons) being able to pick up the slack (and then some) for the passive restraints (discs, ligaments, and to a lesser degree, bone) to protect against injury. Without a doubt, it's one reason why some folks can be walking around with disc herniations and stress fractures and be completely pain-free: they've got plenty of muscular control taking care of things.
However, just as important as muscular control is the take-home lesson: almost universally, a goal in your training — particularly if you have a history of back pain — is to reduce shear stress.
Not surprisingly, in the aforementioned study from Cholewicki et al., researchers found that the sumo deadlift style reduced load shear force by 8%, as compared to the conventional deadlift style.(3) I suspect that using a trap bar would reduce this load by even more, as it brings the bar even closer to the center of mass and ideal axes of rotation.
Now, I'm not saying that conventional deadlifting is necessarily dangerous; it's just an exercise where you have slightly less wiggle room with your bad form because there's a bit more shear stress. And, that leads us to our next point...
11. Position impacts the stability of a spine in a given situation.
Everyone knows that squatting and deadlifting (or anything involving appreciable compressive loading) with a rounded lower back isn't a good thing. But, not many people understand why. This quote might help explain it:
"In the presence of axial compression with and without sagittal shear force, flexion considerably increases the intradiscal pressure while extension reduces it. In other words, under an identical compression force, disk pressure is predicted to be noticeably larger in flexion than in extension."(4)
In other words, put a bar on your back. Arch, and you reduce stress on the discs. Round over, and they go sky-high. Dr. McGill noted that full flexion reduces strength in buttressing against shear stress by 23-43%.(2)
It's one reason why many disc herniations can actually tolerate quite a bit of compression as long as the spine is positioned in neutral. It's also the reason why people with flexion-intolerant low-back issues — the classic disc patient — need to stop freakin' sitting in flexion so much!
You might be wondering why there's a 21% "range" of strength reduction in flexion — and my next point will answer that very question.
12. Disc hydration status affects spine function.
When you go to bed — and stay there for hours and hours — your spine has no compressive loading because of the horizontal position. As a result, the discs "hydrate" overnight, and expand as a result. Expanded discs create a stiffer spine — and one that is less effective in buttressing shear stress.
I've known of people who have herniated discs picking up pencils or just tying their shoes — and the one thing that seems to be consistent with all of them is that it happens first thing in the morning. First-thing is just not a good time of day to flex the lumbar spine. You need to give the discs time to "dehydrate."
The good news is that most of this reduction in disc hydration status occurs in the first hour that we're awake (we actually lose a little bit of our height over the course of the day). It's one reason why I'm not a huge fan of training first thing in the morning.
However, I know that's the only time of day a lot of you can train, so I usually suggest the following:
1. Wake up a few minutes earlier, and make sure you're standing.
2. Take a hot shower to get your body temperature up (and give you a little kick in the pants).
3. Plan to avoid flexion at all costs in your training sessions — including flexion exercises without axial loading.
4. Do a thorough warm-up (shameless plug #2: crafty of me, huh?).
13. Recognize that different athletes break down in different places for the same reason.
Have you ever seen a 10-year-old tear an ACL? Never. Strain a hamstring? Probably not. Break a leg? Absolutely!
Now, how about 25-year-olds doing the same injurious activities? They tear ligaments and muscles a lot more frequently than they break bones.
It's not that these populations are markedly different in the activities they face. Sure, the older athletes may compete at a higher velocity, but if anything, that should just increase the frequency of injuries, not change the type of injury they face.
Lower back injuries are no different. Take a kid with poor ankle and hip mobility, insufficient rotary stability, and no anterior core strength. Send him out to play baseball, and you've got a recipe for a spondylolysis (vertebral fracture). The bone isn't fully developed, so it's the path of least resistance.
Give an adult those same problems and send them out for a company picnic softball game, and you'll see disc herniations/bulges, lumbar strains, and ligamentous problems. It's just core instability and hip/ankle immobility across the lifespan.
Perhaps the most intriguing example I've ever seen with this was a 16-year-old athlete will an avulsion fracture of his ischial tuberosity. This is the point on the pelvis where the hamstrings attach.
Rather than just strain the hamstrings, the bone gave way first and he ripped a piece of it off at the muscular attachment site.
14. Ankle mobility closely interacts with hip mobility and lumbar stability.
I mentioned ankle mobility in my last point. It's quite possibly the most overlooked contributor to lower back pain, in my experience.
First off, modern footwear can be pretty crappy because of the big heel lift many sneakers have. Obviously, the biggest example of this is high heels; we all know loads of women who have complained of lower back pain after a long day in heels. The back pain is very predictable: if you put someone on their toes, you shift the center of mass forward, and the lumbar erectors must work overtime to counteract this repositioning.
It's really not much different than a pregnant woman experiencing back pain because her belly increases anterior-weight-bearing.
Second, when you have a restriction in ankle mobility — particularly dorsiflexion (toe-to-shin) ROM — you're likely to round over when squatting as you approach the bottom position of the squat. If the knees can't come forward sufficiently, you'll max out your hip mobility, and then move to the lumbar spine to get that ROM. It's why so many people can only squat deep when they have ten-pound plates under their heels. And, it's also why some folks can't even hit parallel when they don't have their goofy bubble-heeled sneakers on.
Third (and this is going to take some thinking), shifting the weight forward increases pronation. When you overpronate, you increase recruitment of all the muscles that serve as "anti-pronators:" most notably, the external rotators of the hip. After chronic abuse, these muscles can become chronically short with marked soft tissue restrictions. To keep this discussion from getting out of hand, I'd encourage you to check out this old newsletter of mine on this very topic.
As I outlined earlier, if you restrict motion at the hip, you're just waiting for lower back pain to come along — and the research certainly supports the idea that a hip internal rotation deficit (HIRD) is a big part of this problem. Research from Ellison et al. found that 48% of those with lower back pain have insufficient hip internal rotation.(5)
Obviously, the first step is to get to work on the causes of the ankle mobility deficit, but it's also important to address the HIRD. To get the ball rolling, I prefer aggressive soft tissue work: sometimes too aggressive, as my sorry ass learned recently.
For the record, the picture at right is the closest I've ever come to pornography in any of my articles here at T NATION. TC is going to be so proud. Well, maybe not.
Foam rollers also work quite well to get things started. This soft tissue work should go hand-in-hand with stretches to regain hip internal rotation. At right is one example we use quite a bit.
The truth is that I'm only getting warmed up. Stay tuned for the next installment, where I'll kill off a few myths, drop some knowledge bombs, and throw in some videos.
1. Van Dillen LR, Bloom NJ, Gombatto SP, Susco TM. Hip rotation range of motion in people with and without low back pain who participate in rotation-related sports. Phys Ther Sport. 2008 May;9(2):72-81.
2. McGill, SM. Personal Communication. October 2006.
3. Cholewicki J, McGill SM, Norman RW. Lumbar spine loads during the lifting of extremely heavy weights. Med Sci Sports Exerc. 1991 Oct;23(10):1179-86.
4. Shirazi-Adl A, Drouin G. Nonlinear gross response analysis of a lumbar motion segment in combined sagittal loadings. J Biomech Eng. 1988 Aug;110(3):216-22.
5. Ellison, JB, Rose SJ, Sahrmann SA. Patterns of hip rotation range of motion: a comparison between healthy subjects and patients with low back pain. Phys Ther. 1990; 70(9): 537-541.
Imagine putting a barbell on the guy on the right (or for that matter, the guy on the left).
Arch and you reduce stress on the spine.
The ischial tuberosity is the point on the pelvis where the hamstrings attach.
Soft tissue work is anything but soft, as these bruises and scrapes attest.
This type of foam-roller work helps regain hip internal rotation.
About Eric Cressey
Eric Cressey is a highly sought-after strength and conditioning coach and owner of Cressey Performance, just west of Boston. Eric has worked with athletes of all levels, from youth sports to the professional and Olympic levels. He publishes a free weekly newsletter and daily blog at EricCressey.com.
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